In the realm of 3D printing, makers often face a significant hurdle when attempting to bring 2D images to life in vibrant, multi-color prints.

In recent years, the field of multi-color 3D printing has seen many solutions emerge, as numerous 3D printer manufacturers have launched printers equipped with multiple extruders or automatic filament management systems. With these types of printers, makers can create 3D-printed works with up to a dozen colors. However, the more colors that can be achieved, the higher the cost of the 3D printing device and filament tends to be.

Furthermore, in the current landscape where CMYK 3D printing technology is not yet widely accessible, even owning a 3D printer capable of creating 16-color prints may not suffice to turn 2D images into finely detailed, color-accurate prints with varied lightness, tones, and shades. This is largely due to the relatively limited variety of colors available in the filament market, making it challenging to achieve this goal.

But today, we're going to show you some magic by introducing HueForge, a software that creates richly hued, painting-like reliefs from 2D images, even with just two colors. More importantly, this technique works well with all the Snapmaker 3D printers—Snapmaker Artisan (Dual Extrusion), Snapmaker J1/J1s (IDEX), and even the Single Extrusion Models like Snapmaker 2.0 and Snapmaker Original.

Before we jump into the exciting tutorial, let's first get more specific about HueForge.

How HueForge Works

As introduced on its official website, "HueForge is software which allows you to create detailed multi-color 3D Prints using only Swap-by-Layer through a process we call Filament Painting".

To put it more explicitly, HueForge achieves multi-color design through the layering of filament. The question then arises: how do we, or HueForge, know which filaments can exhibit different color effects when stacked, and which are more easily able to show varied color effects through layering?

This brings us to the concept of Transmission Distance (TD). For example, many painting software applications allow users to set the transparency of brush colors. When transparency is set to 0%, layering the same color multiple times does not result in any variation in shade. However, when transparency is set above 0%, repeating the layering process makes the color on the canvas progressively darker, until it matches the color with 0% transparency.

Similarly, the higher the TD value, the higher the "transparency" of the filament shown in the print, making it easier to achieve a richer depth of color through stacking, either by itself or with other filaments. Vise versa.

Filaments produced by different manufacturers often have different TD values, and the stacking of the same filament, different filament, or different colors of filaments can all result in a variety of richer colors and shades.

It is also because HueForge achieves multi-color design through filament layering that it can convert a 2D image into a 3D printable relief model. Therefore, to accurately set and preview the visual effects of relief models in HueForge, it is necessary to specify the correct TD values of the available filaments. To facilitate user operation, HueForge includes a vast library of filaments covering many mainstream manufacturers' products, with corresponding TD values that have been tested and can be directly applied. For filaments not in the library, HueForge also provides a simple method for testing the TD value, which is detailed in the third section of this article.

In short, once you import a 2D image into HueForge and set the TD values for the filaments to be used, you can design a unique relief model by adjusting the number of layers and the layering order of different filaments.

Sample Tutorial

Now that you have a basic understanding of how HueFore works, let's practice using our sample image with your Snapmaker right away! The tutorial will be completed using the Snapmaker Artisan 3-in-1 3D Printer and the Dual Extrusion Model, while the process and steps are compatible with other Snapmaker printers.

You can use our recommended settings or make any adjustments to create your unique relief from it.

Step One: Create the Relief Design with Hueforge

1.   Download Hueforge.

       You can purchase and download HueForge from its official website.

        HueForge is compatible with Windows and MacOS 11+, and there are several pricing plans available for different usage needs.

2.   Download and import the sample image into HueForge.

 

       Sample Image.png  

       Drag the file into the interface of HueForge or click File > Open File > Image in the top menu to import the image.

       After the image is successfully imported, the relief preview (on the right) will be displayed next to the imported image.

       By default, the preview consists only of black, grey, and white colors, which you can change in later steps.

        HueForge supports images imported in the formats of PNG, JPG, JPEG, and WEBP.

        If you want to create reliefs without a background, you should first remove the background from the original image using graphic processing applications like Photoshop before importing it into HueForge.

3.   Specify the parameters of the relief.

           ⅰ. In the General Options and Operations panel, adjust the basic parameters of the relief. 

              Our recommended settings are shown in the picture (except for the width and height, which you can adjust according to your own needs).

           ⅱ. In the Model Geometry panel, adjust the geometric parameters of the relief. 

                Our recommended settings are shown in the picture. We only modified the Min Depth to 0.48 and the Max Depth to 4.00, while you can also try experimenting with other parameters on your own.

4.   Select the filament used to print the relief.

      On the Filament Library panel, drag the color icon of the selected filament to the slider in the Color Sliders panel. The colors we use are black, green, red, orange, yellow, and white.

        If the filament you own is not listed in the default library, you can also add new filament and test

        You can use filaments in the recommended colors above if they happen to be at your hand or use filaments in any other colors that you prefer and that are available around.

5.   Tweak the visual effect of the relief with the color sliders.

       In the Color Sliders panel, move the sliders up and down to change the layering of filament.

       Our recommended settings are shown in the picture (except for the TD values, which vary with filament and require additional testing for filament not listed in the default library).

        High-TD white filament can be used as a smoother for color or brightness, generally placed between two colors that need to be smoothed.

6.   Generate the key information.

       In the General Options and Operations panel, click Describe.

       A window will pop up displaying key information needed for slicing: layer height, initial layer height, filament info, and most importantly, the filament swap instructions. You can either click to copy the information elsewhere convenient for later use, or click to generate it again when needed.

7.   Export the STL file.

       In the top menu, click File > Export STL to export the STL file for slicing.

Step Two: Configure the Parameters with the Slicer

       To demonstrate how to add the M600 command (for filament changing), we will use PrusaSlicer for slicing.

1.   Import the STL file and adjust the slicing parameters.

ⅰ. In PrusaSlicer, import the STL file, click Print Settings, and switch to the Advanced mode.

           ⅱ. Adjust the parameters as specified below, as they are necessary for a successful relief print:

1. 1. • Perimeters: 1
      • Fill density: 100％
      • Fill pattern: Rectilinear
      • Top fill pattern: Monotonic Lines
      • Bottom fill pattern: Monotonic Lines
      • Detect thin walls: On

            ⅲ. Check and make sure that the layer height and the first layer height set in the slicer are consistent with the Layer Height and Base Layer already set in HueForge.

            ⅳ. Set the Black filament (or the "start with" filament described in the key information, as shown below) as the default filament for the model.

2.   Add the filament changing command (taking our HueForge configurations as an example).

           ⅰ. Click Slice now. It might take a while for the G-code preview to display.

            ⅱ. Along the layer bar on the right, find and click Layer 12 (1.16 mm).

            ⅲ. Right click the plus sign that appears beside, click Add color change (M600) for: and select the Extruder 1 to add the filament changing command at that layer.

            PrusaSlicer does not support the settings for the Dual Extruder Module. Therefore, you have to use one of the two extruders, which you choose to heat by operating on the Touchscreen, to print the entire relief.

           ⅳ. Along the color selection window, change the color to Green.

            ⅴ. Click Slice now to save the added command.

            In the following steps, each time after you add the command and change the color, be sure to click Slice now to save the settings.

            ⅵ. Along the layer bar on the right, find and click Layer 16 (1.48 mm).

            ⅶ. Add the M600 command and change the color to Red.

            ⅷ. Along the layer bar on the right, find and click Layer 25 (2.2 mm).

            ⅸ. Add the M600 command and change the color to Orange.

            ⅹ. Along the layer bar on the right, find and click Layer 33 (2.84 mm).

            xi. Add the M600 command and change the color to Yellow.

            xii. Along the layers bar on the right, find and click Layer 38 (3.24 mm).

            xiii. Add the M600 command and change the color to White.

      In this way, the printing will pause at the layer where the M600 command is added so that you can manually change the filament.

3.   Double-check all the settings.

           ⅰ. Check if the key slicing parameters are specified as required.

            The commands you have added will be saved even if you switch to the Print Settings tab.

            ⅱ. Click Slice now again.

            ⅲ. In HueForge, click Normal in the General Options and Operations panel to switch to the slicer preview mode, and check if the preview looks the same (or almost the same) as the G-code preview in the slicer.

4.   Export the G-code to the printer and start printing.

5.   Manually change the filament when the printing pauses as configured.

            ⅰ. After the printing pauses at a specific layer, tap on the Touchscreen to set the temperature of the working nozzle to 200℃.

            ⅱ. After the nozzle is heated up to 200℃, manually unload the filament.

1. 1. 1. Open the front cover of the toolhead.
      2. Press the extruder buckle downwards to expand the dual-gear extruder.
      3. Pull the filament out of the toolhead.

            You may need to use a little force or heat the nozzle to a slightly higher temperature to assist the unloading.

            ⅲ. Manually load the new filament.

1. 1. 1. Insert the filament into the toolhead until it is pushed right into the feed hole of the hot end and is extruded from the nozzle.
      2. Gently push the filament down until the old filament is completely extruded out and the new filament runs out smoothly.
      3. Press the extruder buckle back in place and close the front cover.

            ⅳ. On the Touchscreen, tap to resume printing.

            ⅴ. Repeat the above steps each time when the printing pauses as configured.

How to Test the TD Value of Filament

Testing the TD value of the filament used to print the relief is very important, as it relates to whether the relief preview you see in the HueForge matches the actual printing result. You can take the following steps to conduct the test.

1. In the local directory of HueForge, locate the Step_Test_Sqaure.stl file in the Tools folder and import it into HueForge. The interface should display as below.
2. In the Color Sliders panel, adjust the first four sliders to match the ones displayed in the picture.
3. At the bottom of the Filament Library panel, click New Filament to add the filament you want to test.

4. Take a photo of the filament in a well-lit environment and use the eyedropper tool to extract the color of the filament from the photo.
5. In the Add Filament window, specify the necessary information about the filament. You can keep the TD value at its default setting for now, as it won't have any impact on the testing result.
6. Click and drag the color icon of the newly added filament into the second slider to replace the default grey color.
7. Export the STL file, configure the settings in the slicer, and print the model out.
8. In HueForge, adjust the TD value of the tested filament in the Color Sliders panel until the relief preview looks as close as possible to the print.

Useful Tips for Large Prints

For large-sized prints, you can increase the success rate of printing by following these tips:

• Adjust the first layer height appropriately. For example, when printing objects with a horizontal or vertical size of 300 or 400 mm, you can set the layer height as 0.2-0.28 mm (just for reference).
• Turn off the part cooling fan during printing.
• Preheat the heated bed to the target temperature for 15-20 minutes before printing to stabilize the bed deformation. It is also recommended to raise the bed temperature appropriately (to 70-75°C, for instance).
• Wait until the first layer is printed successfully before leaving, as it can take some time to read the file before printing, during which the temperatures of the nozzle and heated bed may decrease.
• Adjust the height of the working nozzle as necessary to enhance the first layer printing result.
• If there are strings on the print, you can reduce the nozzle temperature by 5-10℃ to improve the print quality.
• If you are using Snapmaker Artisan:
  • After preheating, calibrate the Z offset of the left and right nozzle, and use the right nozzle to calibrate the heated bed (either at 25 or 81 points).
  • When heating and loading the nozzle, make sure to heat the heated bed simultaneously to avoid sudden drops in the bed temperature.
  • Use the glass side of the build plate and apply printing adhesives.

 

Learn more about Snapmaker Artisan 3-in-1 3D Printer.

 

Whether direct drive or Bowden, different extruders work pretty much the same way — the filament is inserted into the extruder, and the motor and gears drive it into the hot end, which will then use electrical heating (e.g., resistance heating) to melt the filament. Finally, the liquified material is evenly extruded out of the nozzle onto the heated bed, stacking up layer by layer to form a 3D object.

 

Most printers only have one extruder, while some have two. So, which is better — single or dual? If your pocket is deep enough, two is better than one for the most part. In fact, dual extruder 3D printers have become more and more common in recent years, and are even trending to replace single-head printers.

 

Why are dual extruder 3D printers trending?

 

Dual color or material combo

 

Dual extruder can print objects using two different filament colors or types on the same print. This allows more complex and colorful prints.

 

Snapmaker Dual Extrusion 3D Printing Module mounted on Snapmaker 2.0

 

Two-color printing is not that uncommon. Even with a single extruder, similar effects can be achieved by manually changing the filament. However, if you want to use two different materials on the same object, for example ABS and TPU to print a flexible/rigid combined object, manually changing filament can be very troublesome, and is prone to failed prints because optimal settings for the two materials are different. Rather than risking it with great effort, it's better to just print them separately and glue them together.

 

 

In contrast, when using a dual extruder printer, you can set different parameters for each extruder directly in the slicer software, and complete dual material printing in one print job.

 

Breakaway and soluble support

 

The ability to print easily detachable (or “breakaway” as a trade name) and soluble supports is perhaps the primary reason most people buy a dual extruder 3D printer. Removing supports after printing can be tedious and time consuming. And if you don’t do it properly, your print can be ruined by marks, pits, divots or blemishes on the surface finish.

 

Breakaway support

 

Breakaway support materials are formulated to have low interlayer adhesion and be mechanically brittle, so they break away cleanly with little force. Soluble materials can dissolve in water or other solvents. PVA (Polyvinyl Alcohol) is the most commonly used one. It is highly sensitive to moisture and decomposes when in contact with water. Taking advantage of this property, it can be used as a support material to fill some difficult-to-reach geometries that allow liquid to flow into. After printing, soaking the print in water dissolves away the supports, leaving behind a smooth printed surface.

 

Soluble support

 

Some additional functions

 

Dual extruders also enable some additional functions, such as a backup mode. In single-extrusion printing, if the active extruder fails or clogs, or the filament runs out, the idle extruder can take over and finish the remainder of the print. This improves overall uptime and reliability.

 

Improved slicing software

 

It is mechanically simple to build a dual extruder system by just duplicating parts, but the real challenge is in the software. The popularity of dual extruder goes hand in hand with improvements in slicing software. The slicing algorithms are better at planning optimal toolpaths for dual extruders to minimize travel moves and retracts. They also do well in assigning different model parts to be printed by each nozzle to maximize use and minimize idle nozzles. Software advancements have made dual extruders more user-friendly and reliable, allowing wider adoption.

 

Drawbacks of Dual extruder

 

With the growth of the 3D printing industry, desktop printers are more affordable and easier to use nowadays. Dual extruder has also become a common feature on many budget products, allowing more users to experience the benefits of dual printing. However, dual extruders also have some flaws:

 

Source: Simplify3d

 

• Cross contamination and collision: In dual-color printing, the idle extruder can ooze material due to residual heat and cause contamination when it glides over the printed part, or even bump into it if the nozzle is too low.
• More maintenance: Twice the hot ends means twice as many parts to check, clean and replace when there are jams or clogs.
• Relatively smaller build volume: Since the extruders themselves take up some length on the X axis, dual-head printers will have a smaller build volume compared to single-head given the same printer frame size. This is especially noticeable when upgrading from single to dual head.

 

The maintenance and build volume drawbacks are probably unavoidable, but contamination and collision can be solved. The most common way to deal with contamination is setting retraction in the slicer, which prevents oozing by temporarily reversing the filament in the extruder during travel moves.

 

Another method is using a prime tower — printing another object concurrently with the main print, giving oozing or leaking inactive nozzles a place to purge material instead of on the print. Similar solutions include ooze shield, which surrounds the printed part so any oozed material gets wiped off on the shield when the nozzles are close to the print.

 

Ooze shield (Source: IceSL)

 

Some printers also have a wiping device installed directly on the machine at the same height as the nozzle, so the nozzle can wipe off any residual when passing over it. Simple yet practical.

 

Snapmaker J1s's nozzle wiper

 

However, these don't solve the collision issue, and prime towers/ooze shields increase time and material usage. In comparison, mechanically lifting the inactive extruder seems more versatile. For example, the Snapmaker Dual Extrusion Module uses motors to automatically raise/lower the extruders, avoiding both contamination/collisions, and allowing fast, quiet extruder switching.

 

Auto extruder lifting of Snapmaker Dual Extrusion Module

 

Finally, there is the ultimate solution — an IDEX (Independent Dual Extruder) 3D printer. As the name suggests, the two extruders can move independently. When printing with one head, the other can park inactive in a corner with no need for heating. When both are active, they print independently with no interference. However, to further reduce ooze impacts, IDEX printers may still employ wiping devices, retraction, prime towers, etc. during dual extrusion printing.

 

Independent v.s. dependent dual extruder system

 

IDEX has some advantages over regular dependent dual extruders, but also poses some challenges for manufacturers and users.

 

Snapmaker J1's printing in duplication mode

 

Advantages

 

• Minimal contamination and collision: In dual printing, the idle extruder parks in a corner rather than moving along with the active extruder. And before the next printing job, the extruder can wipe off any oozed material using a wiping device or prime tower. So IDEX can effectively eliminate ooze contamination and collision issues.
• Mirror and duplication printing: IDEX printers can double the productivity by printing two mirrored or identical objects simultaneously. Very useful for mass-producing small items like chess pieces.

• Less weight and higher accuracy: Compared to a mechanically linked dual extruder, one single extruder of an IDEX printer is lighter, allowing faster moves with less floating mass and higher accuracy.

 

Disadvantages

 

• More difficult to manufacture: Precisely aligning the independent extruder carriages and extruders demands tight manufacturing and assembly tolerances.

• Trickier calibration: Calibration is one of the biggest challenges in IDEX printer design. The two independent extruders not only need to be calibrated with the bed, but also to each other in the X, Y and Z axes. Poor calibration can cause cracks or even print fractures due to poor layer adhesion.

• Higher cost: IDEX not only has higher R&D costs on software, but also requires an independent or semi-independent motion system on the hardware side, including motors and carriages for each extruder. If not sharing an X-axis, additional linear rails, leadscrews or belts are also needed. These factors mean IDEX printers generally cost more than regular dual extruders.

 

How to choose from single extruder, dependent dual extruder, and IDEX

 

Here are some things to consider when making the choice:

 

Single Extruder

 

• Simplest and most affordable option;
• Easier to calibrate and maintain;
• Limited to single color/material prints.

 

Dependent Dual Extruder

 

• Dual color or material printing without much filament waste;
• Allows dissolvable and breakaway supports;
• Costs more than single extruder;
• Potential collision risks and idle oozing issues;
• Trickier calibration.

 

IDEX

 

• Can print identical or mirrored objects twice as fast;
• Dual color or material printing without much filament waste;
• Allows dissolvable and breakaway supports;
• Minimal risk of collisions or ooze;
• Highest cost and calibration needs.

 

In general, for most hobby printing, a single extruder is sufficient. For two color prints or easier support removal, consider a dependent dual extruder. For advanced applications or speed, an IDEX system may be ideal if budget allows. Hope you can find your dream printer!

 

3D printing technology is advancing by leaps and bounds. One moment we are discussing making small toys to entertain children, and the next second we see news that a 3D printer has built a concrete building that can withstand an 8-magnitude earthquake. Given time, "3D printing a 3D printer" also seems possible.

 

But leaving prospects aside, what hobbyists and makers care more about are still desktop 3D printers — what types there are, how fast they print, and how much they cost. If you like getting to the bottom of things, or ever tried DIYing a 3D printer before, you must also have pondered this question: how do they move?

 

XYZ, I3 and CoreXY are currently the most popular styles of desktop 3D printers. This is how they move: the machine has one or several axes in the X, Y and Z directions of the 3D coordinate system. One end of each axis is equipped with a motor to provide power. Synchronous belts or leadscrews then convert the motor's rotation into linear motion along the X, Y and Z directions. Finally, with the linear guide rail systems in the 3 directions, the machine can position the nozzle at any point in the 3D space formed by the axes, extrude the filament, and create a 3D object.

 

Linear guide rail system on Snapmaker Artisan

 

Why are guide systems important?

The guide systems mainly serves 3 purposes during printing:

• Precision: Realize tight tolerance, prevent wobble, and ensure the print head or heated bed installed on the guides moves linearly along the predetermined direction;
• Smoothness: Reduce friction with bearings or rollers, and contribute to smoother motion;
• Reliability: Guiding structures with excellent rigidity can improve machine reliability and contribute to more consistent prints over time.

 

The variety of guide systems

In general, the guide systems used on 3D printers include:

• Wheels & profiles
• Linear rods & bearings
• Linear rails
• Embedded linear rails (introduced by Snapmaker)

 

Wheels & profiles

Source: Kywoo3D

 

Among all the guides, the combination of wheels and profiles is probably the most common and cost-effective. There are typically 3 to 4 rollers running along the V- or T-shaped groove of the profile to guide the movements.

POM wheels

Source: Printer Mods

 

The outer ring of the wheels is most commonly made of POM (Polyformaldehyde), and the inner ring is made up of steel and ball bearings. POM has high strength, low deformation, and excellent abrasion resistance, making it especially suitable for making printer wheels. With proper use, POM rollers can last hundreds of hours. Some manufacturers also use PC (Polycarbonate) to make wheels, which have even higher strength and longer life, though at a slightly higher price.

PC wheels

Source: I3D Service

 

To ensure linear motion, the wheels should grip the profiles properly. Too loose and vibration can occur at high speeds. Too tight will increase wear — accumulated debris can pile up between the wheels and rails, causing bumpy or jittery motion. So users need to adjust the wheel tightness based on how the printer works, clean debris, and replace wheels when necessary. Compared to other guides, the wheel and profile combo requires more frequent maintenance.

 

Additionally, plastics have lower rigidity than metals. Wheel deformation during motion is hard to avoid, so printers using wheels generally have lower precision compared to those with steel guides.

 

V-slot profile

Source: 3D Printing Store

 

The profiles commonly used on 3D printers are available in two types: V-slot profiles and T-slot profiles. As the names suggest, the main difference between them is the cross-sectional shape. Different profiles pair with different wheels to achieve good guiding effects.

 

Since the profiles are customizable, inexpensive, and with sufficient performance, the combination of wheels and profiles is the top choice for many DIY 3D printer builds.

 

Advantages

• Good guiding performance, cheap and useful;
• Abundant options, widely available;
• Easy to install, use, and modify;

 

Disadvantages

• Lower precision;
• More prone to vibration;
• Requires more frequent maintenance.

 

Linear rods & bearings

The limitations of wheel and profile guides have led DIYers and manufacturers to shift more attention to another combination with superior precision and stability — linear rods and bearings. In the past few years, rod and bearing guides have become almost synonymous with guide systems for 3D printers. At least 2 rods and 2 bearings are needed for each axis of the printer. The bearings either wrap or cling to the rods, while connecting to carriages mounted with an extruder or heated bed, to guide the linear motion.

 

Linear rods with linear bearings

Source: Amazon

 

A linear rod, aka smooth rod, is simply a cylindrical steel rod, available in various sizes — 3D printers typically use 8mm diameter ones. Rods can be machined to high dimensional accuracy with very smooth surfaces. Paired with ball bearings, properly assembled rods can achieve fairly good linear motions.

 

And yes there are also drawbacks of being smooth. When used for guidance, the rods need to be fixed at both ends with metal clamps. Also, bearings can not only move linearly but also rotate 360° around the cylinders. That's why they need to be attached to bearings on another parallel rod to let the extruder or heated bed move linearly. Parallelism between two rods can be challenging, especially for DIYers.

 

So, using shaft guides means higher precision and stability on one hand, but also larger footprint and weight, along with higher assembly difficulty on the other.

 

Snapmaker 2.0 Linear Module sectional view (linear rods in dark grey; U-groove bearings in yellow)

 

The bearings used with rods are mainly U-groove bearings and linear bearings made entirely of steel. U-groove bearings resemble wheels that can roll along the rods. Linear bearings have a cylindrical sleeve on the outside, with several rows of balls on the inside that can cycle along the shaft. Both can accomplish smooth guidance with minimal friction.

 

Rods and bearings are long lasting, only requiring occasional cleaning of buildup on the rods and lubricating the bearings. If the rods are enclosed in a housing instead of acting as the frame (e.g. Snapmaker 2.0's Linear Modules), disassembling the housing and lubricating the bearings is straightforward. However, replacing worn out bearings after prolonged use can be slightly tricky.

 

Advantages

• Excellent guiding performance, high precision, moderate cost;
• Abundant options, widely available;
• Low maintenance frequency;

 

Disadvantages

• Larger footprint and weight when enclosed;
• Parallelism can be a problem;
• Replacing bearings can be tricky.

 

Linear rails

Linear rail, also referred to as linear guide, has been trending in recent years. The steel rail part has a track on each side, and the sliders nested on it contain 2 sets of ball bearings that can cycle along the tracks. In addition to industrial 3D printers, more and more desktop manufacturers are also using linear rails in their high-end product lines, such as Snapmaker's J1.

 

Source: Adafruit

 

Although both are made of steel, when it comes to actual work, linear rails are less susceptible to bending and vibration compared to rods. This is mainly attributed to their unique mounting method. Rods are only fixed at both ends, while linear rails have mounting holes at regular intervals on the surface, allowing them to be tightly secured to the housing or other support structures.

 

This ensures stable linear motion and improves print quality on one hand, and increases the speed limit by preventing excessive shaking at high speeds on the other. This is one of the reasons J1 can achieve high-speed printing.

 

Snapmaker J1 IDEX 3D printer with linear rails

 

During assembly, linear rails can guide a single axis without pairing, saving space and weight to make the machine more lightweight and compact. There is also no need to worry about rail parallelism.

 

Source: Birailmotors

 

It all sounds great, but what's the catch? The price. Rough calculations show that while the sliders for linear rails have similar prices to the bearings for rods, the rails themselves cost about 2.5 – 4 times that of a pair of rods at equivalent lengths. In comparison, rods are cheap and good enough. Weighing the extra cost against performance gains, most DIYers would still opt for rods and bearings.

 

For maintenance, linear rails are similar to the former, requiring regular lubrication of the bearings. Exposed rails also need occasional cleaning.

 

Advantages

• Very high precision;
• Supports high-speed printing;
• Small footprint, convenient to use;

 

Disadvantages

• Cannot serve as support structures, needs to be installed on profiles, etc.;
• Expensive.

 

Embedded linear rails

Instead of using the above guides directly, some manufacturers, for the purpose of advancing technical capabilities or catering to specific products, are also exploring better solutions. Embedded linear rails are what Snapmaker chose for its Artisan model.

 

Snapmaker Artisan with embedded linear rails

 

The core strengths of linear rails lie in the high rigidity of the steel rails and the precise, smooth motion enabled by the ball bearings. These advantages are preserved in embedded linear rails.

 

When making the Linear Modules, Snapmaker embeds two steel strips into the inner walls of the aluminum alloy housing, then CNC grinds the steel precisely into rails with micron-level machining accuracy. Also, with the wider embedded rails, rigidity is further improved without increasing weight, better suiting high-power CNC operations — after all, Artisan is a 3-in-1 product, and ordinary 3D printers do not require such extreme rigidity.

 

Compared to directly mounting linear rails on the surface of extrusions, embedding the steel rails inside the linear modules prevents dust buildup on the rails, reducing maintenance frequency. It also makes the modules more lightweight and compact, so that an expensive machine does not end up looking like a DIY enthusiast's project. However, embedding linear rails does pose considerable manufacturing challenges for the producer, with no cost advantage over normal linear rails.

 

Advantages

• Same as linear rails: very high precision, supports high-speed printing, small footprint;
• Rail rigidity further improved;
• Lower maintenance frequency with rails enclosed;

 

Disadvantages

• Expensive;
• Not suitable for DIY.

 

Summary

 

 

Characteristics of TPU filament

TPU (thermoplastic polyurethane) is a soft resin that is resistant to bending, tension, and friction. And

it also has excellent chemical resistance. TPU is one of the most commonly used materials in 3D printers, because it can be used to make parts with rubber-like elasticity and impact resistance.

 

Advantages

• It is relatively inexpensive, easy to handle, and can produce parts with softness that cannot be obtained by the SLA printing method.
• Adhesion between layers is strong. By adjusting the wall thickness and infill, it is possible to make parts with various characteristics.
• Depending on the application, you can make soft parts like rubber tires or strong, unbreakable parts like gaskets and seals.

 

Disadvantages

• TPU is a material that easily absorbs moisture. Moisture absorption can cause bubbles or poor flow during printing, which can have a negative impact on products. Therefore, it requires more attention to storage and drying than other materials. For more information, check out this article: 3D Printing Filament Storage and Drying: Why and How.
• As explained in the next section, printing is technically more difficult than PLA. Supports are difficult to peel off, so it is necessary to create shapes that require as little support as possible.
• Like PLA, heat resistance is not good, so care should be taken.

 

 

Why is printing with TPU so difficult?

Differences in difficulty between different types of extruders

Proper pressure must be applied from the extruder to feed the filament out of the nozzle.

Bowden extruder used in some 3D printers has the advantage of having a small and lightweight head. But the long distance from the extruder to the nozzle makes it difficult to extrude TPU filament, which is soft and cannot be tensioned. Therefore, it is challenging to print TPU on a Borden-type 3D printer. Generally, higher temperatures, slower speeds, and avoidance of retraction are used.

The direct extruder used by Snapmaker allows the extruder and nozzle to be in close proximity to each other, allowing the proper pressure to be applied to even the softest TPU filaments. As a result, temperature and speed settings can be set to fit TPU, and retraction can be performed to enhance the quality of products. But still, printing with TPU is not easy.

 

 

Difficulties arising from the wide variation of TPU filaments

Like other filaments, TPU filaments come in a variety of types. In particular, Shore hardness is a characteristic measure of TPU. Generally, a smaller Shore hardness indicates softer material and a larger Shore hardness indicates harder material.

Even with the similar TPU materials, it is more difficult to print well than generic PLA because settings must be adjusted over the characteristics of the filament.

 

Troubles and solutions when using Snapmaker

Cannot extrude

Snapmaker direct extruder uses a combination of a single gear and opposite roller to extrude the filament. Soft TPU may bend in Snapmaker extruder and cannot be extruded properly, causing filament jamming.

• Lower the Printing Speed and Retraction Speed to increase the flow.
• It is recommended to use Polymaker TPU95-HF for TPU printing due to its high stiffness. 
• Carbon residue in the inner wall of the nozzle can lead to greater resistance. You can change the nozzle regularly.

Depending on the types of TPU filaments, Snapmaker may not be able to solve the problem. If the problem persists, please refer to the Snapmaker forum. You may find solutions from other users.

 

 

Deformation during printing

The flexibility of TPU allows for deformation during modeling due to the thin-walled structure of the structure and its own weight.

• It is recommended to modify the structure or add infill.
• Increasing the flow rate may prevent deformation. In this case, the molding object will be slightly larger.

 

Ragged object

Insufficient amount of extrusion tends to cause this problem. As well, too much or too fast retraction can cause a ragged object due to bubbles.

• Increase the extrusion flow. 
• Slow down the printing speed to secure the amount of extrusion per unit time.
• Reduce retraction distance and speed.

Note: Although it makes the product slightly stiffer, use the infill pattern gyroid for hollow structures to reduce the possibility of retraction.

 

 

Stringing

Stringing is one of the most common problems that occur when printing with TPU. It is difficult to completely avoid it due to its characteristics, but there are ways to reduce it as much as possible.

• Slightly decrease printing temperature.
• Accelerate travel speed.
• Enable Retract at Layer Change option.

Note: Increase retraction distance and decrease retraction speed are common answers, but they are inapplicable to Snapmaker due to mechanical differences, which would increase the possibility of filament jamming.

 

 

Unable to detach from the build plate

TPU has strong adhesion to the heated build plate. Depending on the print settings, it may be difficult to peel off the object from the print sheet.

• Use the Z offset to move the nozzle an extra distance (about +0.1 mm) from the build plate.
• Detach objects while the build plate is still heated with Pallet Knife. Be careful not to touch the hot surface of the build plate.
• Decrease initial build plate temperature.
• Use duct tape or masking tape to the print sheet.

Note: Generally speaking, a new print sheet provides stronger adhesion.

 

Snapmaker Luban settings

Here are some specific settings for Snapmaker Luban to solve the above problems.

Note: It is recommended to use Polymaker TPU95-HF for TPU printing.

 

Material settings

• Printing Temprature: 225℃
• Fan: ON
• Build Plate Temperature: 50-60℃
• Extrusion Flow: >120%
• Retraction Distance: 2.5mm
• Retraction Speed: 15mm/s 

Printing settings

• Layer Height: 0.1-0.3
• Initial Layer Height: >0.25
• Initial Layer Line Width: 150%
• Shell Thickness: >0.8
• Infil Pattern: Gyroid
• Printing Speed: <25mm/s
• Travel Speed: >70mm/s

Note: Typical settings can be downloaded here. Use these .json files on Snapmaker Luban. Click on the gear icon at the upper right, then click on the import icon in the bottom left corner of the settings. Check the image below.

 

 

Printing samples

Depending on your ideas, TPU has unlimited possibilities. Please enjoy Make Something Wonderful!

 

Crawler

 

Toy Parts

 

Fitted Lampshades

 

Flexible Toolbox             Speaker Sealing

 

 

Introduction

For many, the ability to print out nearly any object one could imagine from the comfort of their home is equal parts astonishing to inspiring. Now imagine if you could transform those relatively robust plastic creations into rigid long-lasting masterpieces. Well, I’m here to tell you that the process is surprisingly easy, and I’ll help guide you along every step of the way. Let’s get right into it, starting with the process overview, which details the key aspects of converting plastic 3D printed components into their concrete counterparts.

 

 

CAD Modeling: Turning the concept of your project into a three-dimensional object.

3D Printing: Converting the STL file into a tangible part, via additive manufacturing. 

Silicone Molding: Casting a negative silicone mold of the 3D printed parts.

Concrete Casting: Filling the negative silicone mold with concrete. 

Decorating: Arranging modular planters and adding decorative plants and materials.

 

How to Video

https://youtu.be/40XSeIGZyiU

 

Concrete Planters

Project Introduction

When I started this project, I wanted to design a modular planter that was able to be quickly configured into different arrangements. The design would have to be relatively minimalistic to ensure ease of 3D printing, silicon molding, and concrete casting. In addition to these design constraints, I wanted certain components to be stackable, adding another level of modularity to the system. 

 

Design Considerations

When I started the design of this project I wanted to have the ability to quickly rearrange the planters and pavers to create different layouts. I achieved this modularity by sub-dividing the base shape which was an elongated hexagon into 3 unique shapes. The main shape is a pentagon, which has three different configurations, depending on the application of that component. For example, if you wanted to create a vertical stack up, you would start with a base planter and then add as many hollow planters as you would like. Because these shapes are derived from the base elongated hexagon, they can be added in a repeating pattern to create new and unique shapes.

 

Figure 1.0: Base Shape constructed using four hexagon pavers.

 

Figure 1.1: Two examples of the different configurations that are possible with the modular components.

 

Bill of Materials

• PLA Filament
• Mold Star 30 Silicone
• Quikcrete Mix
• Potting Soil
• Decorative Filler Rocks
• Decorative Moss
• Succulents
• Hot Glue Gun
• 3D Printer
• 330-Grit Sandpaper
• 220-Grit Sandpaper
• Plastic Sheet
• Mixing Bowl
• Mixing Stick
  

 

CAD Modeling

The first step is turning the concept of your project into a three-dimensional version, which will allow us to export as an STL. This STL can later be processed by the slicing software, and we will get into that in the next step. 

 

Slicing and 3D Printing

Before we can begin printing, we need to first convert our STL file into G Code. This is carried out by the software Snapmaker Luban, which “slices” the models into thin layers and creates tool paths in the form of G Code, allowing the printer to interpret the data and turn the compilation of individual layers into a printable part. For a more detailed explanation of slicing and G Code, check out this article: Slicing and G Code: The Bridge Between 3D Model and 3D Printer. 

 

Figure 1.2: Slicing the hollow planter component in software Snapmaker Luban.

 

Post Processing

Once the printing process is completed, we can begin post-processing the components. Due to the geometry, most of the parts don’t need support material during printing and therefore most of the surfaces on the print are smooth. The only exception to this was the hollow planter, which could be printed in an orientation that would allow for no support material. However, I wanted the parts all to be oriented the same to ensure the fillet on the top surfaces was consistent. I started by sanding the parts using 220 grit sandpaper, this removed any major surface blemishes and gave the parts a relatively smooth finish. From there I applied filler primer to all the parts and let them dry. The filler primer did an excellent job filling in any small voids or gaps between layer lines. From there I sanded the parts once again, this time using 330 grit sandpaper, resulting in an almost perfectly smooth surface finish. Although sometimes tedious post-processing these parts is a key step in this project to ensure a high-quality finished product. Since the silicon mold will capture any small blemishes in the part, which will in turn be reflected in the concrete casted parts. 

 

Figure 1.3: Sanding filler primed hexagon paver with 330 grit sandpaper.

 

Mold Setup

Since I used a trial bottle of Mold Star 30 silicone I had to optimize the shape of the mold shell. I started by arranging the components I planned to cast in CAD and then designed the shell around them. Making sure to leave enough space between components to ensure the silicon mold hard rigid enough walls to support the concrete during curing. The mold shell was also 3D printed although, I didn’t post-process it at all since the surface finish on the perimeter of the silicone mold wasn’t important. The next step was to hot glue the post-processed prints to a base, I used a plastic sheet from an old picture frame. Then I placed the mold shell around those components and hot glued it as well. It’s important to make sure there are no gaps between the mold shell and the base, otherwise, the silicone will slowly leak out since it’s not very viscous. I didn’t use any mold release spray for this project, but you could use some if you wanted to ensure easy removal of the 3D-printed parts once the silicone cured. In my case, I was able to remove the parts with minimal work even without any release spray. 

 

Figure 1.4: All components and mold shell layed out and hot glued to plastic base.

 

Mixing Silicone

There were a few reasons I chose Mold Star 30 silicone for this project. The primary reason was that this specific silicone rubber doesn’t require a vacuum for degassing and has a low viscosity, which allows it to easily flow into small areas. To prep, the platinum silicones are mixed 1A:1B by volume, meaning no scale is necessary. I chose to pour each bottle into a common container and mixed them until a homogenous solution was achieved. Once the silicone was ready to be poured I slowly began filling the Mold shell, making sure to fill in all the little channels between the components and the shell. The last step in the silicone molding process was to agitate the silicone. This is a very important step, which removes any trapped oxygen bubbles within the silicone. If bubbles aren’t properly evacuated from the silicone, it will likely impact the surface finish on your final concrete parts once you cast the silicone mold. This could have been avoided had I used a vacuum chamber to degas the silicone, although I didn’t have one at my disposal. In the end, the features that were generated in the concrete parts due to residual trapped air bubbles ended up being a surface feature I came to appreciate and enjoy in the parts.   

 

Figure 1.5: Filling the mold shell with Mold Star 30 silicone. 

 

Component Removal

I started the component removal process by pealing away the flexible plastic base followed by pressing the silicone through the mold shell, leaving just the silicone mold with the entrapped 3D printed parts. From there it was as simple as pressing the 3D printed parts out since most parts were glued directly to the plastic base. Except for one part, which required me to add relief cuts to the silicon mold. These cuts would prove to be extremely useful once it came time to remove the concrete cast parts.

 

Figure 1.6: Silicone mold, once all 3D printed parts have been successfully removed.

 

Mixing Concrete

There is an expansive list of potential concrete mixes one could use for a casting operation like this. I opted for the Quikcrete sand/topping mix since the powder was relatively fine and I was able to easily source it from my local HomeDepot. The first step in mixing the concrete was to pour an appropriate amount of concrete powder into a mixing bowl, then added water. The general rule of thumb is to get the concrete to a consistency similar to that of oatmeal. You want the concrete to be wet enough to flow into the silicone mold nicely, but not too wet. When concrete is mixed with too much water it dries weaker, overly porous, and is more prone to cracking. 

 

Figure 1.7: Concrete mixing process, just before adding water and stirring the mixture.

 

Concrete Casting

When casting the silicone mold with concrete, it’s important to pour slowly. This helps to limit the number of air bubbles that are trapped within the mold. To aid in the evacuation of trapped air, I once again agitated the silicone mold by vibrating it. This brought the vast majority of air bubbles to the surface, although there were still some trapped lingering bubbles. These air pockets ended up giving a unique surface finish on the final parts and became something I liked.    

 

Figure 1.8: Carefully filling the silicone mold with the concrete mixture.

 

Post Processing

Once the concrete had dried completely I removed the parts from the silicone mold. The next step was to sand down the small amount of “flash” on the bottom surface of the parts. This is caused by the silicone mold not being filled all the way with concrete. When this happens the concrete experiences capillary action, which causes the concrete to stick and rise on the perimeters of the mold. Additionally, I sanded a few regions on the hollow planter parts to ensure they would have a slip fit with other components when stacked.   

 

Figure 1.9: Sanding concrete hollow planter with 220 grit sandpaper block.

 

Decorating

With our post-processed components completed, it's time for the fun part. I started by laying out an arrangement that I liked. From there I decided which areas would have plants and soil, and the areas which would only have rocks and moss. The stack-ups of the hollow planters were filled with soil, to help provide nutrients for the succulents I planted within them. As a finishing touch, I added some small rocks around the succulents and filled a few other areas with rocks and moss. I opted for a succulent and moss-themed design, but there are many other styles one could choose. For example, a desert-themed planter with cactus and sand.  

 

Figure 2.0: Adding small river rocks to cover the soil surrounding the succulents.

 

Finished Product

 

 

Alternate Applications

The process of turning 3D printed parts into a silicone mold and then using it to cast in another material could be applied to a wide range of projects. Although the complexity of these 3D printed parts is somewhat limited, there are design choices that can be made to overcome these limitations. Additionally, the material you choose to cast with can vary as well, for example, you could replicate this project but use chocolate instead of concrete. The possibilities are nearly endless. If you’re interested in trying out this manufacturing process but aren’t sure where to start, here are some project ideas to get you started:  

• Concrete Vases
• Desk Organizers
• Concrete Coasters
• Candle Holders
• Phone Stands
• Business Card Holder
  

 

Conclusion

At first glance, it probably seemed like a daunting task to produce a consumer-quality concrete component from a few 3D printed parts and some silicone. But once the manufacturing process is broken down into its fundamental steps, it becomes a much easier project to comprehend. Hopefully, as you’ve progressed through this article you’ve developed a better understanding of how to turn 3D printed parts into concrete masterpieces and found some inspiration for your own DIY projects along the way.

 

Now go out there and Make Something Wonderful！

 

Hello, Maker!

As known to all, initial layer adhesion is critical for FFF 3D printing, on which we would spend a lot of effort, such as tuning the slicing parameters or using various tools. That’s also why Snapmaker specially designed a detail-rich print sheet to minimize the troubles. Now, let’s take a look at this product and learn some basic daily maintenance and cleaning skills.

Design & Material

The print sheet of the Snapmaker 2.0 machines consists of two parts: the steel plate and surface stickers on both sides.

The steel plate is made of carbon steel with high toughness and strength. Though the print sheet can be bent slightly, it will immediately return to its original flatness once the force is stopped, thus ensuring that the entire printing platform can always be kept flat during printing. At the same time, its magnetic design also provides great convenience for removing prints and replacing the print sheet.

Although not fixed with screws, the strong magnetic attraction between the print sheet and the heated bed helps them stick firmly together. Without intended human force (which must be very strong, actually), the print sheet will not move during printing.

The sticker of the print sheet is made of polymer materials, of which the surface is specially processed to further improve the adhesion effect of the initial layer. Though named as “sticker”, it is highly flame-retardant, oxidation-resistant, as well as heat-resistant. 

Thanks to its material properties, the print sheet sticker can effectively accelerate the cooling process of the extruded filament when the initial layer is printed, making it adhere to the print sheet faster and better, and also reducing the possibility of wrapping. Internal tests have shown that our specially designed sticker can effectively improve the initial layer adhesion of a wider variety of filaments, compared with the Polyetherimide (PEI) stickers or coatings used in many other printing platforms.

Moreover, the print sheet of Snapmaker 2.0 has stickers on both sides. This not only ensures the flatness of the steel plate when heated, but also increases the utilization of the print sheet. You can switch the front and back sides at will to use, thus reducing the frequency of replacement.

How to Avoid Print Sheet “Injuries“

Traces or marks may be left on the print sheet due to various reasons over repetitive use. If not handled in time, they can affect the printing quality. For example, filament residues on the print sheet may negatively impact the initial layer adhesion in the next printing. What’s more, if filaments of different colors are used over two successive printings, the bottom of the latter print is likely to be branded with an undesirable “gift” from the former print, as shown below.

Also, dented traces pressed out by the nozzle on the print sheet may leave some “3D tattoo” on your future prints.

Some of these traces are reversible and can be erased by later cleaning, while others are permanent. Therefore, before we proceed to cleaning methods, let’s go over some preventive measures and precautions that can help you avoid such “injuries” to the print sheet.

1. Don’t set the Z height too low.
   Many Makers, including myself, tend to set the Z height as low as possible during the heated bed leveling or after the printing starts, so as to reduce potential problems that can happen to the initial layer adhesion. However, the nozzle can easily leave dents on the print sheet in doing so. At the same time, the extruding of filament may be hindered or even stopped if the nozzle is too close to the print sheet, which could give rise to discontinuous lines, uneven surfaces of the printed object, or even nozzle jams. A failed printing process can be restarted, a jammed nozzle can be cleaned, but the dent left on the print sheet is irreversible. What’s more, an excessively low Z height may cause the filament to stick too much to the print sheet, bringing about more troubles in the cleaning process afterward.
   
   
   
   
2. Don't take out or elevate the print sheet when the machine is still working.
   Sometimes when the printing of the initial layer is not going well and thus you decide to remove the filament and start over, you might just take out the print sheet directly without pausing the machine. In this case, the distance between the nozzle and the print sheet will suddenly decrease, and the nozzle may leave dents or traces on the print sheet as a result.
   
   
3. Use masking tapes on the print sheet.
   As one of the favorite tools among Makers, masking tapes can improve the adhesion of the initial layer. Every time before a new print, you can just conveniently tear the old tapes off and apply new ones. More importantly, they won’t damage the print sheet. If your print sheet already has traces that can affect printing quality, you can cover them with masking tapes to minimize their annoying effects.
   
   There are things you should pay attention to when using masking tapes:

• • Do not overlap masking tapes, for the nozzle may lift the overlapped part of the tapes when printing the initial layer. Beyond that, take special care when sticking the edges of masking tapes. When the 3D printing module finishes heating and moves from the bottom left of the print sheet to the target area, it may easily scratch up the edges of masking tapes.
  • The area covered by masking tapes should be larger than the printing area; otherwise, the nozzle might also scratch the edges of the tapes.
  • Level the heated bed again after applying the masking tapes before printing. This is because the tape itself has a certain thickness, so printing without a second leveling may cause extra problems.
    

4. Apply washable glue to the estimated printing area on the print sheet before printing.
   Note that one or two thin coats of glue are enough, and make sure the glue is applied evenly to avoid lumping. When the printing is completed, you can easily remove the glue traces with water and a towel. Besides, it’s better to clean the glue immediately after printing when the heated bed has not cooled down, or you can clean the glue with warm water.
   
   
   
5. Set the Line Count to 3 or above if you choose Skirt as the Build Plate Adhesion Type in the slicer.
   Setting the build plate adhesion type helps enhance the initial layer adhesion, but when you select skirt and set the line count to a value smaller than 3, there are chances that some filament residues would stick to the print sheet and be difficult to remove.

Cleaning Tips

We have collected some practical cleaning tips from our colleagues and forum, which can be roughly divided into physical and chemical ones. When there are filament residues or grease on the print sheet, you can try some of the methods below.

Physical Method

You might be wondering: Nobody cooks on the print sheet, so where does the grease come from?

In fact, our skin produces natural grease that might stick to the print sheet while we operate the 3D printer. Besides, dust from the air can also fall on the print sheet. The accumulation of grease and dust over time will inevitably affect the adhesion performance of the print sheet. Therefore, we need to clean the print sheet regularly, even if there is no filament residue. If you print frequently, it’s best to wipe the surface of the print sheet with a clean towel after each printing.

The simplest and most effective physical method to remove filament residues is as follows.

1. Heat the heated bed to a temperature above 70℃ (gloves are suggested to protect your hands).
2. Clean the print sheet either with the palette knife in the Snapmaker tool box, or with a similar plastic tool.

Be careful about your force in the process so that the palette knife doesn’t damage the print sheet. It’s recommended that you hold the front part of the knife with great care, concentrate the force of your fingers, and slowly clean the residues.

The palette knife might leave some tiny scratches during this process, which are tolerable as long as they don’t affect the flatness of the print sheet.

Chemical Method

Actually, we don’t recommend that you use the chemical method. As mentioned before, the surface of the print sheet sticker is specially processed for better adhesion performance. However, the chemical solvents may damage the surface. Therefore, use the chemical methods as a last resort and with caution even if they can help sometimes. Only when the physical method doesn’t work and you have no other print sheets for replacement can you try the chemical ways.

According to tests, the 70% (or above) isopropyl alcohol (IPA) may help remove filament residues yet must be used in a well-ventilated area with protective measures. Additionally, ensure the heated bed has cooled down when using this method because the IPA is highly volatile.

 

It should also be noted that for filament residues accumulated for a long time, neither physical method nor chemical method is of much help. Therefore, it’s better to clean the print sheet after each use.

If one side of the print sheet cannot be used anymore, switch to the other side. If the damaged side is uneven with filament residues, you need first remove the residues before switching, or the flatness of the print sheet could be influenced. If both sides of the print sheet are damaged, you can place an order at our official store for a new print sheet with a few clicks!

 

We hope this article could be useful for you!

In the future, Snapmaker Academy will bring you more fun topics, so stay tuned!

If you are interested in other content of 3D printing, feel free to contact us at support@snapmaker.com or leave your message in the community.

 

Disclaimer

All the methods in this article are for reference only.

Snapmaker does not assume responsibility for loss, injuries, damage, or expense arising from or in any way connected with the methods in this article.

 

You can either watch this video tutorial, or follow the instructions below.

https://www.youtube.com/watch?v=qTsA1QAdlZw

 

Laser engraving is a process of using a laser beam to create permanent marks on a surface, such as wood, metal, glass, or canvas. Laser engraving can be used for artistic, industrial, or personal purposes, such as creating custom designs, logos, signs, or painted canvases.

Some advantages of laser engraving is that it can produce high-quality and detailed images on many different materials, including layered painted canvas. A painted canvas is a type of fabric that has been coated with paint, usually acrylic or oil, to create a colorful and artistic background. Laser engraving on a layered painted canvas can create a contrast between the painted top layer and the underlying canvas colors, resulting in a high-quality, unique, and eye-catching effect.

 

What You Need

• A laser engraver. Ideally, you should opt for the diode laser, as they are suitable for engraving in high detail on layer-painted canvases.

• Work platform hold-down clamps. These will help to ensure your canvas stays in place during the laser engraving process. They are not always needed, but they do provide the security of knowing your projects won't move or shift during the engraving process.

• A laser engraving software such as Luban, to import, edit, and send your image process to the laser engraver. Snapmaker Luban is a free, open-source CAM software developed by Shenzhen Snapmaker Technologies Co., Ltd. It is specially designed and optimized for Snapmaker machines.

• A paint of your choice to coat the canvas. You can use spray paint or brush paint, depending on the desired effect. You can also use multiple colors and layers of paint to create more depth and variety in your artwork.

• A canvas of your preferred size and shape. You can buy ready-made canvases from craft stores or online.

 

General Steps

The general steps to laser engrave on layered painted canvases are as follows.

 

Painting the Canvas

Prepare the canvas by applying one or two coats of your base paint (I recommend flat white to help the color stand out) on the canvas and let it dry completely. For best results, you should apply one layer of paint in two directions, from a distance between 6-12” above the canvas, in smooth, thin applications. This will ensure a nice even finish. You should apply your first thin application on the canvas in a vertical motion, moving across the canvas from left to right, then apply another thin layer in a horizontal motion across the canvas from top to bottom. Depending on what type of paint you choose, drying times can vary. Most aerosol paints typically dry in 15 to 30 minutes.

 

     

 

After having applied one or two layers of your base paint on the canvas, you can now apply your first layer of the colored paint that you chose and let it dry completely. As mentioned above, use the same method.

 

     

 

After applying your first layer of the colored paint on the canvas, you can now apply your second layer of the colored paint that you chose and let it dry completely. As mentioned above, use the same method.

 

     

 

After applying your second layer of the colored paint on the canvas, you can now apply your third layer of the colored paint that you chose and let it dry completely. As mentioned above, use the same method.

 

     

 

After applying your third layer of the colored paint on the canvas, you can now apply your final top layer of the paint color that you chose (in most cases black is a suitable color for first attempts) and let it dry completely. As mentioned above, use the same method. This is the final layer, so for best results, I suggest looking at the top of the canvas, at eye level, and look for any dry spots. With light shining above the canvas, you can see the wet paint shimmering from the light. You can easily identify if there are any unpainted areas, as there will be a dip/dry spot in the wet surface. As stated, depending on the paint you choose, drying times can vary, and most aerosol paints typically dry between 15 and 30 minutes.

 

 

Generating the G-code and Engraving

While your final layer of paint is drying, you can now import your selected image to the laser engraving software and adjust the settings according to the size, resolution, and mode of your image. You can choose from different image modes, such as Grayscale. You can also use online tools, such as ImagR1, to process your image and optimize it for laser engraving.

 

 

In your laser software, import the image you intend to use. After the image is imported and displayed on your screen, you may need to adjust the image settings. Adjust the settings such as the X and Y position to get the image centered. Adjust the size of your image to match that of your canvas selection. In the Processing Mode image settings, Grayscale and Black and White work best. If you have painted the final layer of your canvas a dark color such as black, invert the image. You can further adjust the contrast, brightness, white clip, and grayscale conversion algorithm. For your first few attempts, you should stick with the default settings, as they will give you optimal results.

 

 

After all of your image settings are complete, you can now click Next, and this will take you to the Toolpath process, where you can fine-tune the image toolpath settings. For the highest level of detail, Dot-filled Engraving is the best choice. It takes longer but gives the best results. The best Method of choice is Fill. The best Movement Mode is Dot. For your Fill Interval, this is highly dependent on your image size, in most cases the default setting should work fine, 0.14mm. Your Jog Speed can be left at the default setting of 3,000 mm/min. You can also stick with the default Dwell Time of 5 ms/dot. Now when it comes to Power, this can vary a bit depending on the image. I would suggest using laser power between 35% and 45% for the 10W diode laser, and even less on the higher-power lasers. You can use a test canvas to experiment with different settings and find the optimal settings for your project.

 

 

You can now select Generate G-code and see your final image to be engraved, and the estimated time for the project. This is your last opportunity to fine-tune your settings. If you are satisfied with how everything looks, you can now export the project to the flash drive.

Place the painted canvas on the laser platform and make sure the painted side is facing up and the canvas is lying flat on the work platform.

 

 

Now you can align your laser module, using the touchscreen, with the canvas, according to your image origin position, and adjust the position of the laser using the calibration target for the laser, to be at the proper height above the canvas.

 

     

 

Next, you can run your laser boundary, to further check if the work origin is proper. Make adjustments as needed. Once you are satisfied with the placement, you can start the laser engraving process.

 

 

Once the engraving process has started, monitor the progress and the results.

 

Cleaning the Finished Work

After the engraving is done, remove the canvas from the laser and wipe it with a water-dampened paper towel to remove all residue. Then, wipe it with a dry paper towel to remove the leftover moisture, and let it dry. You may need to repeat this process a few times until you get your machine settings dialed in.

 

Finished Work

 

 

 

 

Introduction to Laser “Painting” on Stainless Steel

So you’ve spent the last few weeks running test array in order to define a set of parameters that will give you a nice set of colors on stainless steel and you’re thinking, “Now what? How do I actually use these colors to make a picture?” Fear not! Help is at hand! In this tutorial, I will explain my step-by-step process for creating an image like the one you see above using your Snapmaker Ray. I assume that the basic steps will port fairly smoothly over to the Snapmaker’s 3-in-1 tools (like the A350T) but I can’t make any promises since I haven’t tried to do it on both machines yet. If you are interested in pursuing projects in laser color marking and haven’t yet done so, I encourage you to start with my tutorial on that subject before diving into the depths of making images.

 

Materials and Useful Accessories

As I note in the other tutorial, my best results to date have come from using “frosted” steel plates of at least 1 mm thickness, sourced from Amazon. I usually use square pieces of 100 mm by 100 mm, with a protective film on both sides that keeps the surface of the steel from getting scratched prior to use. I usually peel the film off just before placing the metal sheet into my Ray, to minimize the chance of getting scratches or fingerprints on the surface. If you do get fingerprints, I recommend cleaning off the steel using a lint-free towel and 99% Isopropyl Alcohol. That leaves a nice, clean surface on which to “paint”. Again, I will be using my aluminum hold-down plate and button-head screws to secure the steel plate during “painting”.

 

 

Laser Parameters Reference File

If you came here after going through my tutorial on Laser Color Marking, you should already have a LightBurn reference file containing a colored test array of squares that sets out the proper laser power / speed / intervals / etc for the different colors you have available. I usually start every new image project by making a copy of the reference file and renaming it with the name of the new image. That helps prevent making changes to the original reference file and potentially losing your set of laser parameters. If you place your test array of colors outside the working area in LightBurn, it will happily just sit there and not be included in any G-code output files you create, but you can still use it to define all your laser color parameters.

Outline of the Laser-color Image Creation Process

Below I list the steps we will follow that will ultimately result in a G-code file that you can load into Luban and run on your Ray. After the outline, I’ll go through each of the steps individually and explain what they mean.

Outline of picture process

1. Select picture

• Best is something with well-defined color areas, little shading, color set close to what is available or can be adjusted to fit what you have.

2. Open picture in GIMP
3. Select by color
   • CTRL + C to copy.
4. Paste as new image
5. Export as JPEG or PNG with label as that color (or color #1 …)
6. Open LightBurn
7. Open file where you have color parameters setup
   • Should have colors in test array outside of active area.
     • Won’t show up in output G-code.
8. Import JPEG / PNG into LightBurn
9. Trace Image (reduce min size to zero from default of 2)
   • Increase Threshold to get all but outer profile.
10. Drag thing you just traced to side and delete
11. Assign a color/raster parameters to that layer
12. Go back to GIMP and delete that color from working image
13. Repeat Steps 3-12 for each color in working image
    • Can combine layers to same color if you want to.
    • Drag each new layer to correct position relative to previous layers.
14. Select entire image and resize to fit steel workpiece
    • I use 90 mm as max on 100 mm square to keep away from hold down screws / washers.
15. Re-zero to put bottom corner at 0, 0
16. Save complete image as new Lightburn Project
17. Check simulation to get idea of time required for all layers
    • Can turn off output of layers to reduce time for a given laser session.
18. When time looks right, save G-code

 

Step 1 Select Your Picture

Given the limited set of colors accessible with our lasers, not every image / picture is going to be suitable for use in the laser color marking process.

Before jumping into this first step, I want to talk briefly about two basic ways to “make” a given color show up in an image: “dithered” and “non-dithered”. In a dithered image, color in a given area is created by combining smaller areas (sometimes single pixels) of multiple colors in your palette in an attempt to present a sort of average / mixed color. The simplest example of this is found in black and white newsprint, where a “grey” pixel is created by splitting a pixel into white sub-pixels and black sub-pixels. From a distance, the eye will visually “average” that pixel into something between black and white. The smaller your sub-pixels, the more different levels of “grey” you can obtain in that spot. The same thing works with colors, originally by combining red, green, and blue (RGB) sub-pixels, but now often adding additional colors to the mix. Looking at your phone or computer screen close-up with a magnifying glass will show you this in action. Using dithering works best when the colors of your sub-pixels are saturated and contrasty, which is typically not the case for many of the colors found with laser color marking on stainless steel. Also, much of the color effect we see on steel comes from the degree of overlap between adjacent laser lines or laser dots, so if we try to use too small of a sub-pixel in dithering, we will likely not get the expected color. For these reasons, I recommend NOT using dithering when trying to make colored images. If I figure out how to do this in the future, I’ll come back and edit this tutorial to reflect that. But for now, let’s just focus on non-dithered images.

Keeping the above in mind, I generally look for images that have clear, well-defined areas of color, with very little shading. Below I show three example images: two that are well suited for this process, and one that isn’t.

 

 

https://pixabay.com/vectors/abstract-colourful-dance-dancer-2029887/

https://pixabay.com/vectors/octopus-animal-cartoon-nature-8576823/

 

Image #1 would be an excellent choice for laser color imaging because its colors are well-defined and quite “contrasty”, and would look good with multiple color replacement sets (if you liked some of your colors better than the ones in the image). Image #2 was an acceptable choice (see the header image on this tutorial), even though it contains a larger number of colors than #1, even though some of its colors are not particularly close to the ones we have available. It depends on how close to the original color set you feel it is important to achieve. As is often the case, I made multiple versions of #2 until I found a color set I liked best.

 

https://pixabay.com/illustrations/landscape-illustration-nature-water-4394746/

 

Image #3 would probably be a poor choice for this process. Even though it has a limited color palette, there is a lot of subtle shading that would be very difficult to replicate. In the end, much depends on your level of patience and willingness to dive into the details of an image.

 

Step 2 Open Your Picture in GIMP

The next step in our process is to start breaking your picture down into its individual color components. There are many different image processing programs that could do many of the rest of these steps, but I chose GIMP for the simple reason is that it is free to use, and quite powerful. Using our Octopus as an example, this is what my screen looks like after I’ve opened the file in GIMP.

 

 

Steps 3-4 Select by Color, Paste As New Image

On the Menu bar, choose Select and then By Color (Shift + O). In this example, let’s start by selecting the background (purple) color by placing the cursor crosshairs on the background and clicking it. The outline of that color (everywhere it exists in the image) will be highlighted by a flashing dotted line. Now click on CTRL+C to copy that color into the clipboard. We then click on Edit on the Menu bar and choose Paste As > New Image (CTRL + SHIFT + V). This will create a new image page that only contains the selected color.

 

 

Step 5 Export This Page

We now go to File on the Menu bar, and select Export. This will open an Export window that will allow you to choose a name for this file and where to save it on your computer. Try to name it something helpful, like “Octopus background color.PNG”. The default file type will be PNG, which is fine. If you prefer JPEG, that should work, too. Our next step will be to import this file into LightBurn, so any image file type the Lightburn can read should work. I have created a folder on my Desktop specifically for Snapmaker Ray project files, so this is where I usually export mine to.

 

Steps 6-8 Create a NEW Copy of Your LightBurn Color Test Array File, and Import the (Single Color) Image File You Just Made

Below is what my computer screen looks like at this point:

 

 

You can see my color test array on the left (outside the work area), a big copy of the background color image file in black and white in the middle of the screen, and my laser parameters Cuts / Layers window on the right side. Select the image with your cursor (you may need to click the Arrow icon on the left side of the screen).

 

Step 9 Trace the Image

With the image selected, right click the cursor (or use the Tools dropdown on the menu bar) and choose Trace Image. Your screen should now look like the picture below. There should be a purple outline of the image. I advise that you change the Ignore less than value to zero (0) and push the Threshold slider up to near the upper end of its range to capture as much detail as possible. Note that if you push the Threshold slider up all the way to its max value, the purple outline will disappear. Make sure not to go that far! Reducing the Ignore less than value will make sure the trace doesn’t ignore small spots of color. Sometimes it is also necessary to play around with the Cutoff slider to make sure you capture everything. When the single color files are exported from GIMP, their “blackness” level will reflect their color “value”, so a lighter color will be exported as more of a grey image than the one we see below. The Trace Image function is looking for where the contrast in the image changes, so adjusting the Cutoff value can compensate for a lower contrast. The idea is just to make sure you “get” all of the colored area enclosed by the trace.

 

 

Step 10-11 Assign Traced Image a Set of Color Parameters and Delete Original Image

Although the screen won’t look any different at this point, what you have done is to create an new layer underneath the original, typically now assigned to the most recent set of color parameters used. You can see this by dragging the top layer away to the side. Underneath you will find a layer that looks the same, but has now been converted into an area which can be “filled” by a color. If it’s the first time you’ve done this step, it will be assigned to the “00” layer and will still be black (look at the list of colors on the bottom of the window).

 

 

If you now click on this new layer, you can then click on one of the other colors at the bottom of the window and it will be assigned to that “cut/layer”. In the picture below, I’ve assigned it to Cut / Layer 09 causing it to now look dark blue.

 

 

Once you have accomplished this, it is okay to delete the original image copy on the right side.

 

 

If you were now to click on the Save GCode button under the Cuts / Layers window on the right, LightBurn would write a set of G-code commands to a file that would “Cut” that image out using the laser parameters set up for Cut / Layer 09. Namely, a laser travel speed of 2500mm/min, a Line Interval Spacing of 0.05mm, and a power of 12.7%, which are the values I previously found to give a nice dark blue. If you decided after this point that you wanted the background to be a different color than Dark Blue, all you would need to do would be to click on the layer and then click on a different color square on the bottom of the window. Note that if you inadvertently assign it to a color that you haven’t defined with your test array, it will choose a default set of parameters from the top of the Cuts / Layers window (White in my case), so if one of your images ends up with an area that is unexpectedly a different color than you were expecting, this may be the cause.

 

Step 12 Return to GIMP and Delete That Color from the Working Image

In this step we return to GIMP and delete the color we have just added to our Lightburn project. This will help us keep track of the colors we have completed and which ones we still have yet to process. The picture below shows what your computer screen should show after you delete that color.

 

 

Step 13 Repeat Steps 3-12 Until You Run Through All the Different Color Areas

From this point on, we are just going to repeat Steps 3-12 for every different color in the starting image. If there are areas in the original image that have different colors that you wish to combine into a single color, simply hold down the SHIFT key while clicking with the mouse on the additional color areas. Alternately, this step can be done in LightBurn by clicking on a given layer and then assigning it to one of the colors already used. This will make both areas part of the same Cut / Layer.

Each time you add a new color layer to the LightBurn Project you should move it to line up with the first layer. You can also do small shifts by adjusting the numerical values in the X and Y boxes when the layer you wish to move is selected. For very small layer movements, it is helpful to zoom into the image.

 

Steps 14-15 Rescale the Layers and Zero the Corner

Once all the color layers are complete and aligned with one another, we use the select rectangle to select all the layers and then enter the appropriate dimension in the Height or Width boxes. If you are using a 100 mm square piece of steel, I recommend a maximum dimension of 90 mm to keep the edges of the image away from the hold-down screws.

 

 

You should also place the corner of the image at the 0,0 position (I always use the bottom left corner as the default zero point, as one of the arrows shows).

 

Step 16 Save the Completed Project As a LightBurn Project

Make sure to save the project at this point, in case you want to come back later and make modifications to layer positions, colors, etc.

 

Step 17 Check Your Laser Time Prediction

By clicking on the Preview icon at the top of the LightBurn window (see arrow below) you can get a good estimate of how long the laser time is predicted to be once you press the START button on your Ray. I have found LightBurn’s estimates to be quite accurate if you have followed the instructions for setting up LightBurn to work with the Ray.

 

 

If you find that the laser time is longer than you wish to babysit the Ray, you can “turn off” layers by switching the Output to OFF in the Cuts / Layers window (see arrow). You can choose to laser anything from a single layer to all the color layers, depending on how much time it will take vs how much time you want to spend babysitting the laser.

 

 

Step 18 Save the G-code to Your Computer and Load into Luban

Whatever layers have their Output ON in the LightBurn Cuts / Layers window will be included in the set of G-code instructions that are generated when you click on the Save GCode button.

 

 

Once you have saved the G-code to your computer, you can start Luban and load the G-code into the Workspace window.

 

 

I will note here that in my attempts to set up LightBurn to work with my Snapmaker, I have somehow ended up with an X offset in the Luban G-code image of 21 mm (negative), which you can see in the above picture. However, the origin of the image generated by the diode laser still uses the red laser crosshair point as its effective origin. So I just ignore the offset in the image on the screen.

Once you have imported the G-code file into Luban, you can upload it to your Ray, position your laser on your workpiece, and press the Start button. If you have opted not to include all of the color layers in the current laser file, make sure NOT to manually move the laser from the origin position in between laser sessions, unless you have established some way to return it to precisely the same position before you burn the rest of the layers. Otherwise, the origins of the different G-code session will likely be in different spots and your colors won’t line up between the sessions.

Below is the final output from my pre-defined color set, following the steps I have laid out above. Total laser time was 3 hours and 50 minutes.

 

 

Image References

https://pixabay.com/vectors/abstract-colourful-dance-dancer-2029887/

https://pixabay.com/vectors/octopus-animal-cartoon-nature-8576823/

 

Greyscale Images

One subset of “images on steel” that I haven’t yet discussed takes advantage of one of the ways Lightburn can deal with images. When you import an image into Lightburn, it immediately converts the image into black and white (or “greyscale” to be more accurate). There are multiple techniques/algorithms that can be used to convert an image into greyscale, including dithering, as we’ve discussed previously. However, it is possible to choose none-of-the-above as a conversion method and to leave the image as a purely greyscale one, with the pixel “magnitude” at each point corresponding to how bright that particular pixel is. Pure black has a magnitude of “0” and pure white has a magnitude of “100”. In Lightburn’s case, this range of magnitudes can be set to any laser power range that you want, such that the “100” magnitude is set by the Minimum % power setting, and the “0” magnitude is set by the Maximum % power setting. This is inverted from what you might expect, because Lightburn assumes you will be using this process to burn images into wood, and the darkest parts of the image (“0” magnitude) will thus need the highest amount of laser power, and the lightest parts will need close to zero laser power. If you have already gone through the process of setting up material test arrays, you should be able to see that certain power ranges pretty well cover a range of colors from very dark to very light. In the image below, I show a particular power range that spans very dark blue to almost white. If you use that power range as your minimum and maximum power settings in the Lightburn cut editor window, you can produce an image on the steel.

 

 

The process you use should look something like the following:

Step 1 Select Your Picture

In this case, the best pictures to use will look reasonably good when converted to black and white (more accurately “monochrome” since we may not be able to find a power range that actually spans from black to white). The example I will use is a picture of Michelangelo’s Pieta statue.

 

 

Step 2 Edit the Picture for Imaging

Here you should edit the picture in an image editor to crop it to the desired aspect ratio, and adjust the contrast, brightness, highlights, midtones, and shadows to work well with the power/color range you have chosen to use for imaging. This is a bit of a trial and error process, since the power/color range is not linear. You will probably need to try a few times to get the image the way you want it. When finished, import the picture into Lightburn, set the proper size, and place the corner at 0,0.

 

 

Step 3 Invert the Picture

As the screenshot below shows, we can use the Adjust Image window in Lightburn to invert the image brightness. This is necessary because the darkest colors in our power range are at the lowest power, which is the opposite of what Lightburn expects.

 

 

Step 4 Set Your Laser Parameters

Using the Cut Settings Editor window, you now will fill out the laser speed, max and min power settings, overscanning range, line spacing, and Image Mode (Greyscale), as shown below. Once you have these values set, use the Save GCode button to create your G-code file.

 

 

Step 5 Import into Luban and Run the Laser

As with the other image “painting” method, now you can import the G-code file into the Luban workspace, align your laser, and generate your image. Below I show a couple of image created using this process. The image on the right used a reduced brightness to give a better dynamic range in the image.

In both cases the laser speed was 2500 mm/min, the line spacing was 0.08 mm, and the power range was 13.8% - 22%.

 

 

 

Image References

https://pixabay.com/vectors/abstract-colourful-dance-dancer-2029887/

https://pixabay.com/vectors/octopus-animal-cartoon-nature-8576823/

Image by Jacques Savoye from Pixabay

 

 

 

Introduction to Light Interference Color

If you are interested in pursuing projects in laser color marking, I encourage you to start with at least a few of the existing YouTube videos about color via light interference. There are many ways to treat steel to obtain colors, but they all take advantage of the same underlying principle: a transparent chromium oxide layer on the surface of the steel creates an interference effect when light reflects from the top and bottom surface of the oxide layer. In our case, we are using the laser to heat or melt the surface of the steel plate in order to change the thickness of that chromium oxide layer. The heated steel reacts with the oxygen in the air and forms an essentially transparent metal oxide (like glass). The color we see is due to light bouncing off both the top oxide surface and bottom metal/oxide interface. These two reflections add constructively or destructively to result in one wavelength of light being enhanced in reflection. As the oxide thickness increases, the enhanced wavelength also increases, resulting in colors that start out blue/violet, and shift towards red. This is the same thing that happens with the colors you may have seen next to steel welds or tempered steel. It is also possible to accomplish the same oxide growth using an electrolyte bath and a voltage / current source. Many of the existing videos are presented from the perspective of Fiber laser owners, which have some additional control “knobs” to what we have on diode lasers, but the general concepts are broadly applicable to any laser system with the capability of heating / melting the surface of stainless steel. That’s how I started these investigations, and it was a great way to get a quick intro to the field. A good example is linked below:

Light interference Colors on Stainless Steel MOPA Fiber Laser Color

Watching the videos above will give you a good idea of the science underlying laser color marking (thin film optical interference) and reasonable expectations about what kinds of colors can be obtained. That’s pretty much the starting point I had when I began my own experiments.

 

Materials and Useful Accessories

A quick note about stainless steel. There are a vast number of different kinds of steel with differing chemical compositions, and the opinions about what the best steel to use for laser color marking seem to pretty much zero in on 304 Stainless (with 201 Stainless being the 2(nd) choice). I have yet to find an explanation of why 304 Stainless seems to work best, so I can’t comment on the truth of this opinion. I’ll come back and edit this later if I find out. Since I’m not trying to get another PhD, I decided to start with 304 stainless and not worry about it for the time being.

 

My best results to date have come from using “frosted” steel plates of at least 1mm thickness, sourced from Amazon. The heat generated by the laser for some of the colors is easily enough to warp the steel due to local heating, so plates thinner than 1mm were harder for me to work with. Ultimately, I purchased an aluminum hold-down plate with many tapped holes and then used Flanged Button Head screws to hold down the edges of the steel plates during laser marking. Otherwise, the plates could bend so much that they could defocus the laser. I used wide washers and more screws to hold down the middles and corners of the steel plate on the “free” sides shown in this picture. The washers provide hold-down points for pieces whose sizes aren’t an exact multiple of the tapped hole spacing.

 

 

Setting the Laser Parameters

My next step was to take a screenshot out of one of the videos that Snapmaker released to show the capabilities of the new RAY system where they BRIEFLY showed a test array for laser color marking one of their engineers had done. That gave me a place to start for laser power, line interval spacing, and laser work speed. From there I began a multi-week dive into the various parameters used to produce different laser colors. Indispensable to that effort was the LightBurn program (https://lightburnsoftware.com/), where I was able to make excellent use of their 30 day free trial period. LightBurn has a built-in option to create test arrays where you can vary the different laser parameters in a consistent way. One example is shown below:

 

In an array like the one above you can see how different settings, such as Line Interval Spacing and Travel Speed, impact the resulting color. You can also leave one of these parameters fixed, and instead vary Laser Power. As a word to the wise, when you start getting close to colors that you like, make sure to try arrays of larger area than the small squares above. Even if a small square looks uniform, a large square at those same setting will often show visual defects that weren’t obvious in a smaller area. I learned (and re-learned!) that lesson many times!

 

Filling an Area with Color (Rastered Lines vs. Dot Filling)

One thing to keep in mind here is that, while the color is primarily dependent on the thickness of the metal oxide you create, there are multiple ways to influence that thickness. Some changes have large effects, while others can be more subtle. Depending on what effect you may be trying to achieve, different ways the laser power is delivered to the steel surface can result in two areas that get the same “integrated” power looking different from each other. Maybe the most obvious example of this comes from (I assume) the “roughness” of the buried metal surface. Here I’m referring to the interface between the transparent metal oxide and the steel. A very smooth metal surface acts much like a mirror (what is referred to as “specular” reflection). Light bouncing off a mirror-like surface reflects off at the same angle as the incoming light. A rough surface, on the other hand, produces what is called a “diffuse” reflection, bouncing light off much more uniformly, over a wider range of angles. In the case of laser color marking, these effects have a strong impact on what colors we see, especially as we look from different angles. If a surface is highly reflective, we may see very different colors in any given area as we change the angle from which we are looking. If a surface is more diffuse, the color will be much more uniform over multiple angles. The “frosted” steel plate surface is an excellent example of this effect. I found that difference in angular color appearance to be particularly pronounced when comparing color markings done using the standard “rastered lines” for filling areas as opposed to Luban’s option for “dot filling”. I suspect this is primarily from the difference in the roughness of the buried metal surface between these two methods of filling space. Whatever the cause, I found the colors obtained from “dot filling” to be much more consistent when viewed from different angles. As always, I encourage you to try out both “dot filling” and “rastered line filling” to see which style appeals to you more. The dot filling approach is generally slower (you are stopping and starting the laser motion MANY more times than with rastering), but it does look better (in my opinion). One significant downside to dot-filling is that it is not available as an option to fill an area in LightBurn. Below I show some images of two butterflies with similar colors (at least in some viewing directions) made using line-rastering (on the right) and dot filling (on the left). As you can see, the colors of the dot-filled areas are much more consistent when viewed from different angles, while the line-filled areas look dramatically different from some angles where the “specular” effect is quite strong. For the butterfly images, I found the dot-filled color areas to look much better from multiple angles, although a more specular area can really “pop” at the right angle.

 

 

Two additional settings/parameters I will discuss are Overscanning and Constant Power Mode / Adaptive Power Mode. They are somewhat interrelated, so I will talk about them together. Overscanning is a parameter in LightBurn that is typically represented as a percentage (%) of your travel speed. This percentage refers only to the speed of laser travel and will extend the length of the laser travel beyond the boundaries of your fill area. For any given Overscanning percentage, a higher speed will result in a larger amount of extra travel. The purpose here is to give the laser time to start moving and get up to the target speed before getting to the area where the laser is to turn on, and then to wait to start slowing down until after the laser has been turned off. A larger travel speed setting will need more space/time for the laser to get up to speed, so making the Overscanning distance a percentage dependent on speed makes sense. Since the laser power is a critical determinant of the oxide thickness, any variations as you move across the fill area will result in color shifts, especially near the edges of the area. If you leave “Constant Power Mode” off, the Snapmaker firmware will attempt to compensate for variations in travel speed by adjusting the laser power. Thus, if the laser is traveling more slowly than the target speed, the firmware will reduce the laser power in an attempt to provide the same integrated power to a given area. Unfortunately, the accuracy of this compensation method isn’t always where it needs to be for laser color marking. I typically found my best color results with “Constant Power Mode” switched ON in LightBurn and the Overscanning parameter set between 10% and 50%. Of the two parameters, Overscanning is much more important than the power mode. If you set the Overscanning parameter high enough, you shouldn’t need to invoke Constant Power Mode at all. I will note here that Luban also includes an Overscanning parameter, but in my limited attempts I could not make it work. If you are sticking entirely with Luban, using Constant Power Mode will be critical, as it is the only way you will have to compensate for speed variations.

 

LightBurn’s Cut Settings Editor Window

Below, I show an image of the LightBurn Cut Settings Editor popup window, where I set the line rastering parameters for the color I have chosen to call “Blue”. We can see that I have chosen a Line Speed of 2500mm/min, a Power of 13.5%, and a Line Interval spacing of 0.05mm. The Constant Power Mode is turned OFF, and the Overscanning is ON and set to 10%. This overscan results in an “extra” 4.17mm being added to each end of the line to allow the laser to get to the target speed before it turns on, and then to slow down after it turns off. The higher the percentage you set, the more extra travel and thus the better chance of hitting the right speed before the laser turns on. On the other hand, this also increases the length of time needed for each line, and thus your entire color marking project. Since the extra distance is only a function of your speed and not the size of the object you’re filling, the time “multiplier” will be worse for smaller areas than for larger ones. In other words, if the object you are filling is only 4mm wide, this 10% Overscanning (at a speed of 2500mm/min) will roughly triple the time needed to fill it, since it adds ~4mm onto both ends of each line. If your fill object is instead 40mm wide, an extra 4mm travel on each side increases the time needed by only 20%. Just find a value that works for you.

 

 

For the sake of convenience, I have tried to find a set of parameters that would give me colors similar to the presets in LightBurn (on the left of the above image), so that any images I created there could look at least something like what I could expect to produce from my laser setup. In the end, I got close with some, less close with others, and way off with a few. Good red and green colors still elude my attempts, for example, while you can have pretty much any kind of blue you want. What follows are my best efforts thus far, for both line-filled and dot-filled colors. They seem to give somewhat different colors each time I switch to a new batch of steel plates, so there is always some fine tuning to be done if I’m trying to hit a specific color. Anything that affects the amount of laser power absorbed at the surface of the metal will change the amount of oxide you get, so differences in surface chemistry and surface roughness will both come into play here. Another factor I haven’t mentioned here is the thermal conductivity of the metal. How much oxide you get will also depend on how quickly heat dissipates from the laser spot. Thus, metals with high thermal conductivity (like copper and aluminum) don’t work for laser color marking. Titanium, on the other hand, has a very low thermal conductivity and absorbs light well at the wavelength of our blue diode lasers, and thus works well for color marking. If I can find some stainless steel with a significantly different thermal conductivity than 301, I’ll test it out to see how this affects the color marking.

 

Example Laser Parameter Sets

Below I show examples of my current “best” set of parameters for both rastered line color and dot filled color. I attempted to create the same set of colors using both techniques, so the missing squares in the dot-filled color example mean that I wasn’t able to find a good set of parameters for those colors.

 

Rastered Line Color

 

Dot Filled Color

 

 

Safety

Laser

You have only one pair of eyes and you need them! Always wear appropriate safety goggles while working with a laser! Fumes and gasses produced during lasering might be toxic. Use an enclosure with a fan and a hose connected to an exhaust (chimney or window).

 

Chemicals

Take time to read corresponding Material Safety Data Sheets (MSDS) before working with chemicals referenced in this article. Although most of them are relatively low dangerous, wear gloves, safety goggles and a respirator mask while handling powders. Keep in mind that isopropanol is a flammable solvent.

 

Ceramic Tiles

These are widely available in construction stores, sometimes referred to as porcelain tiles. The glazed surface should be clean and free of grease, use isopropanol to clean it before using.

 

 

Titanium Dioxide

Available in pottery stores. Despite its white color, it is responsible for black color after lasering. This is mostly due to formation of crystalline defects on the surface of TiO2 particles, as a result of partial reduction of titanium ions at high temperature, especially in presence of carbon and organic substances. These structural irregularities do not reflect the visible light, making such surface-modified titanium dioxide look black.

The well-known and extensively documented Norton White Tile (NWT) method is based on this property of TiO2, as a main component of some common white paints sold in spray cans. This method is limited to black marking on white ceramics and is not covered in the present article.

 

Ultrox - Zircopax Plus (Zirconium Silicate)

Available in pottery stores. A white pigment widely used in pottery, it doesn't change its color at high temperature.

 

Chalk (Calcium Carbonate)

Available in pottery stores and elsewhere. I found it useful to add it to Zirconium Silicate in order to reduce the size of the white dot in the absence of organic binder. Most likely promotes faster cooling of the melted dot due to endothermic decomposition with release of carbon dioxide gas.

 

Frit 3124

Available in pottery stores, used mostly in glazes. A fine powder of glass composed of different oxides and having a low melting point, very useful to obtain color marking on ceramics.

 

 

Kaolin EPK

Available in pottery stores, general purpose aluminosilicate white clay powder.

 

Bentonite Western 325M

Available in pottery stores, extremely fine Sodium aluminosilicate clay powder with a high capacity to swell in water. In absence of organic binder, it plays a role of viscosity-increasing (thickening) agent to slow down the sedimentation of the slurry and to facilitate its even spreading over the surface of the ceramic tile.

 

Pottery Pigments

Available in pottery stores. These are key components for color marking of ceramic tiles, fine powders of specially formulated mixtures of inorganic oxides encapsulated in zirconia glass. Some of these oxides are highly toxic, but in such an encapsulated state they are less dangerous. Yet, please use them with due care, protect yourself!
I tried pigments produced by Mason and BASF. For more pure and vivid colors, avoid using organic binders: they produce carbon black while burning under the laser beam, which makes the color darker (unless this is your desired effect).

 

 

Polyvinyl Pyrrolidone (PVP) K-90

Available in stores of materials for home-made cosmetics. A water-soluble binder and thickening agent. Helps to decrease the dot size. Can be used as a 2% solution in isopropanol (attention: full solubilization may take up to 72 hours with occasional agitation).
Most likely, PVP could be replaced by Polyvinyl Alcohol, but I had no chance to test it.

Unfortunately, the carbon black formed during laser burning of PVP and other organic binders makes them incompatible with white marking of black ceramic tiles. Also, colors get darker if such binder is used, for example, red becomes brown.

 

Isopropyl Alcohol (Isopropanol)

Available in general hardware and construction stores as a paint or lacquer thinner. Flammable, but not very toxic solvent miscible with water. Yet, take all safety measures!

Avoid using isopropanol with high content of water from a pharmacy, if no other option, accordingly remove water addition from the slurry recipes below.

 

 

Process

In this article, I will limit myself to a description of processing raster pictures. Vector images are easier to process, if necessary, laser parameters can be adjusted to get best results.

The process consists in addition of material by melting it on the surface of the ceramic tile. This is not engraving, the glaze of the tile is not getting removed, but it slightly melts on the surface together with added material. The intensity of the laser beam does not affect the darkness of the resulting dot in a wide range of laser power. This means that a grayscale image cannot be rendered directly, through variation of the laser power, but only through picture pre-treatment while converting it to a black and white dotted image, a process called dithering.

 

Picture Pre-Treatment

Not all pictures would give suitable dithered images even if best algorithms are employed. This topic could be a subject of a whole separate article, I will only provide some general recommendations here.

 

Picture Quality

Your selected picture should have enough resolution, contrast and sharpness, the background should be blurry enough. The minimal resolution should be 10 dots/mm (254 DPI). Graphic pictures (sketches, drawings, engravings, pictures with enhanced contours) will be rendered better than soft halftone photos.

For soft halftone photos with smooth transitions, I would recommend the use of special software or plugins to transform it into an artistic sketch or drawing, often this gives very interesting final results.

 

 

External Photo Editor

In an external photo editor, you can not only adjust brightness and contrast of a picture with more precision and accuracy before dithering, but also improve sharpness, perform crop, adjust resolution, convert to grayscale, add vignetting and even proceed with dithering. This would give you full control of the process before importing the picture into Snapmaker Luban, even the possibility to delete or add individual dots after dithering.

Please note that it is normal if the photo before final levels adjustment looks oversharpened.

 

 

Also, the external photo editor would be useful to separate colors for multi-color applications.

For white on black process, the picture colors should be inverted before the final levels adjustment and dithering.
For pictures with smooth tone transitions, it would be appropriate to use some artistic filters like G'Mic Illustration Look available in GIMP or Krita software and maybe some minor manual dodge/burn adjustments.

 

 

For final curve adjustment (using, only for example, Adobe Photoshop Levels tool), I would recommend the following generic parameters (provided the picture looks well-balanced on the screen): 

• Black slider of Output levels: 130 to 200 (to prevent dots overlapping)
• Midtone Slider: 1.50 to 2.00, depending on the picture

 

 

After this adjustment the picture should look considerably underexposed, but this is required in order to get normal rendering as a result of the whole process. Similar Levels tools are available in other photo editors as well. This is the simplest, yet efficient way to prepare your photos for lasering.

I prefer a slightly more complex approach, using frequency separation and adjusting the levels only in the low-frequency background layer. This way the sharp contours are better preserved, yet no dot overlapping occurs in dark areas. Advanced photo editing skills are required in this case. 

 

 

If you prefer to perform dithering in an external editor, your picture resolution before that should match the expected laser Fill Interval processing parameter in Snapmaker Luban (for example, a resolution of 10 dots/mm or 254 DPI is equivalent to 0.1 mm fill interval). For dithering, I would recommend Stucki or Floyd–Steinberg algorithms. Note that Adobe Photoshop has a similar method in its conversion to Bitmap tool, under Image Mode menu line, it is called Diffusion Dither.

 

 

The dithered picture below is obtained in a different external editor (Photoline), which I prefer, using Stucki algorithm. Do not forget to save the dithered picture in bitmap (.bmp) format, otherwise the quality may suffer during import in Snapmaker Luban.

 

 

You can also use other laser-engraving softwares to control the whole process, but their descriptions are not the topic of the present article, in any case the basic principles stay the same.

 

Importing into Snapmaker Luban

Once imported into Snapmaker Luban, previously adjusted grayscale pictures may require scaling to match the predefined working area. Then proceed with dithering, better using Stucki or Floyd–Steinberg algorithms. Do not forget to switch to the GREYSCALE processing mode. If the picture was not adjusted well enough in an external photo editor, some limited tweaking can be performed using Contrast and Brightness sliders (the picture should look considerably underexposed on the preview), but I would recommend adjusting levels elsewhere before importing. It is better to use Snapmaker Luban sliders only for fine tuning.

 

 

If your picture has been dithered in an external photo editor (recommended), switch to B&W processing mode after importing the bitmap file and scaling. Please note that your picture resolution should match the expected laser Fill Interval processing parameter in Snapmaker Luban (for example, a resolution of 10 dots/mm or 254 DPI is equivalent to 0.1 mm fill interval), otherwise you will get unexpected results. The Threshold slider in this case affects only the preview of the dots on the screen, not the final result (except its extreme values of 0 and 255), so do not rely on the preview, it could be misleading.

 

 

Slurry Recipes

General considerations: the powders should be carefully mixed in a dry beaker before adding liquids, and even more carefully mixed after. Protect yourself, apply safety measures!
The proposed recipes are just examples, yet a few months of experimentation stand behind. You are free to unleash your creativity!

 

Black

This one has many similarities with classical Norton White Tile (NWT) process, with the following particularities:

• Full control over the final result
• Considerably cheaper
• No highly toxic and highly flammable solvents involved
• Deeper black color, higher contrast
• Slightly larger dot (254 DPI recommended)
• Better for drawings
• A bit less good for soft grayscale pictures with smooth transitions

In a dry polyethylene beaker, carefully mix the following components (by dry volume):

• Bentonite Western: 1 volume
• Kaolin EPK: 1 volume
• Titanium Dioxide: 1 volume

Add the following liquids, carefully mixing after each addition:

• Isopropanol: 2 volumes
• Water: 1 volume
• 2% PVP in isopropanol: until ready for application

The readiness for application is based on experience and desired effect: the thicker the final slurry, the thicker the layer on the tile. For better results, the layer should be thin enough, this would give smaller dots. A too thick layer may not work at all. Observe the way the slurry flows out of a bamboo stick: several drops a second should be OK.

 

 

White

In a dry polyethylene beaker, carefully mix the following components (by dry volume):

• Bentonite Western: 2 volumes
• Frit 3124: 1 volume
• Chalk: 1 volume
• Ultrox: 2 volumes

Add the following liquids, carefully mixing after each addition:

• Isopropanol: 2 volumes
• Water: 2 volumes
• Isopropanol: until ready for application

PVP as a binder and thickening agent is not suitable in this case, due to undesirable carbon black formation at high temperature.

The readiness for application is based on experience and desired effect: the thicker the final slurry, the thicker the layer on the tile. For better results, the layer should be thin enough, this would give smaller dots. A too thick layer may not work at all. Observe the way the slurry flows out of a bamboo stick: several drops a second should be OK.

 

 

Color

In a dry polyethylene beaker, carefully mix the following components (by dry volume):

• Bentonite Western: 1 volume
• Frit 3124: 1 volume
• Pigment of desired color: 1 volume

Add the following liquids, carefully mixing after each addition:

• Isopropanol: 2 volumes
• Water: 1 volume
• Isopropanol: until ready for application

PVP acts as a binder and thickening agent. It is not suitable if you want to get vivid colors, due to undesirable carbon black formation at high temperature.

Otherwise, for darker colors but smaller dots, 2% PVP in isopropanol can be used in final addition.

The readiness for application is based on experience and desired effect: the thicker the final slurry, the thicker the layer on the tile. For better results, the layer should be thin enough, this would give smaller dots. A too thick layer may not work at all. Observe the way the slurry flows out of a bamboo stick: several drops a second should be OK.

 

 

Ceramic Tile Pre-Treatment

Always clean the glazed surface of a ceramic tile with isopropanol before covering with slurry, lens cleaning wipes are well suited for that.

 

 

Always mix well the slurry immediately before application: it has a tendency for sedimentation, especially if it does not contain PVP.

To remove particulate matter, always filter the slurry through an old nylon stocking or sock before application.

Cover the tile by an uniform layer of the slurry with a gentle pouring on its surface, followed by tilting in all directions to spread it evenly (isopropanol is flammable, keep away from sources of ignition!). Although it sounds simple, this operation is tricky and requires considerable training to get the desired uniformity of the layer. At the last step, a lazy-susan can help as a centrifuge.

 

 

Also, the slurry can be sprayed on the surface using a pneumatic paint spray system. This would require a preliminary dilution of the slurry with more isopropanol (beware of sedimentation!). Personally, I prefer the pouring approach, since it creates less mess.

Once the tile is covered, let it dry for at least 2 hours at room temperature (isopropanol is flammable, keep away from sources of ignition!) . After that, it is ready for laser treatment.

 

 

Toolpath Parameters in Snapmaker Luban

With a 10W Snapmaker Laser module, the following parameters are applicable for this process:

• Movement mode: Line
• Fill interval: 
  • 0.1 mm for slurries with PVP as a binder (black or dark color)
  • 0.2 mm for slurries without PVP (white or vivid color)
• Work Speed: 3000 mm/min
• Jog Speed: 5000 mm/min
• Laser Power: 70%

Please note that if you preformed dithering before importing into Luban, your picture resolution should match the laser Fill Interval processing parameter in Snapmaker Luban (for example, a resolution of 10 dots/mm or 254 DPI is equivalent to 0.1 mm fill interval), otherwise you will get unexpected results.

 

 

Be careful with Fill Interval parameter, decreasing it below recommended values can lead to overlapping of dots, resulting in local overheating and melting of tile glaze. This may have a negative effect on the image quality, as these overlapped spots would look like less exposed ones (less deep blacks, or less bright white, or less saturated color, depending on the slurry recipe used). This may happen also as a result of improper preliminary photo processing.

The dot size is not only related to the focusing of the laser beam, there are physical reasons for fused material to spread like a donut due to surface tension forces because of the radial temperature gradient.
Smaller dot sizes could probably be obtained with a 1.6W laser due to overall lower temperatures and smaller focus point, but I have not performed such tests with these slurries. 

Please also note that real work speed would in fact be lower due to acceleration/deceleration curves. Therefore for working with vector images, additional optimization of parameters might be necessary.

After that you can export the toolpath to the Snapmaker Luban Workplace, transfer the file to your instrument over Wi-Fi (recommended), adjust the origin point and start the process. For this particular picture on a tile of 200 mm × 200 mm, it took around 7 hours.

 

Ceramic Tile Post-Treatment

 

Wipe the excess of dried slurry with a wet cloth or paper towel and discard it. Wash the tile with water and dish soap, then rinse it with water. Let the tile dry at room temperature from both sides.

And it is done!

 

 

Multiple Colors

An external photo editor can be used to separate color layers and those layers can be processed and dithered separately, giving individual pictures for each of colors in the whole project.

By using guiding rulers attached to the platform, the tile can be repositioned exactly the same way for each color and the same work origin can be set.

 

 

It is important to let the tile dry completely each time before applying a new layer of slurry to avoid the influence of the water absorbed in the ceramic tile during washing.

 

Hello, Maker!

It's time to put your laser engraving and cutting machine into practical application! To unlock the potential of your machine, let’s begin with one of the laser’s most basic applications, engraving pictures.

In this episode, we would like to go through the whole process of laser engraving a picture with you, including material preparation, picture selection and editing, and work parameter configuration.

 

1. Prepare a Material

In the previous episode, Material Selection Guide: How to Choose a Proper Material for Laser Processing, we have introduced some commonly used materials for laser processing and the principles for material selection. Ensure that the material is safe for your health and the environment and that your machine is capable of engraving it. In addition, to engrave a clear picture, we recommend you use a material that has the following features:

• Flat top surface

As a picture is two-dimensional, it can only match a flat surface. If you engrave a picture on an uneven object, the result would be distorted. Besides, a laser engraving and cutting machine usually works with a fixed focal length. During engraving, a level surface enables consistent focusing, and thus guarantees uniform engraving effects.

• Fine and smooth surface

A fine and smooth surface allows more details of a picture to be presented. If the material you want to use doesn’t feel smooth, you can try to polish it. Avoid using porous materials; otherwise, the result will be blurry.

• Light color

Generally, the laser beam engraves materials through burning and makes the surface of the material darker. When engraving on a light-color material, the differences between the lightest and the darkest area could be more prominent, allowing more color gradients to exist in between.

Based on these considerations, we choose basswood, which meets the above requirements and is inexpensive and easily accessed, to demonstrate the process of laser engraving a picture.

 

2. Select a Picture

Picture selection is key to the success of laser engraving. A picture with high resolution and contrast would be our first choice since it contains more minutiae and objects in the picture are more distinguishable. Besides, to retain more details in the engraving product, it would be better to use a picture that includes a lot of transitions from light to dark and doesn’t contain large blocks of solid color.

Understanding the reasons why we choose a picture that has a high resolution, high contrast, and rich color gradient without large blocks of solid color, now let’s see how we can identify a qualified picture.

• High resolution

Image resolution is the detail an image holds. Images are made of tiny pixels (picture elements), or squares of color. Image resolution can be measured in pixels per inch (PPI) or dots per inch (DPI).

High-resolution pictures are at least 300 PPI or 300 DPI, appearing sharp and crisp. This resolution makes for good print quality and is pretty much a requirement for any picture that you want to reproduce.

Just because a picture looks good on your computer screen doesn’t mean it has high resolution. You can’t tell by the length-width dimensions, either. Heavy file size can be a clue, but not in all cases. A simple way to check image resolution is to open up the picture in an image program and view the file properties. You don’t need a fancy program to do this; most computers come with a basic image editing program that will do the trick.

• High contrast

Contrast is the degree of difference between two colors or between the lightest and darkest areas in an image. A high contrast picture features a big difference between light and dark, while a low contrast one has colors close in tone. If a picture is plain white, there are no differences in its color, thus the contrast is zero.

Although it seems easy to distinguish the light from the dark in real life, it may become a little bit tricky when it comes to a static picture. Take the following two pictures as an example, can you tell which one has the higher contrast?

Picture 1 has the higher contrast. Have you got the right answer? Here is a simple way to help you find the contrast differences between pictures:

(1) Prepare a screenshot software.

(2) Respectively cut out small squares of the lightest and the darkest areas from the selected picture. Then, juxtapose the light and the dark squares, so that you can easily see the contrast.

(3) Repeat Step (2) on another picture to get its contrast samples.

(4) Compare the contrast samples from different pictures. The larger difference between the lightest and darkest squares from a picture, the higher contrast the picture has.

 

• Rich color gradient without large blocks of solid color

When engraving a picture, the laser cannot reproduce color. Instead, it creates different levels of light and dark by controlling the amount of energy emitted, and thus recreates the picture. With a lot of transitions from light to dark in a picture, the monochrome engraving product will be more vivid. Conversely, if a picture contains too many large blocks of solid color, the engraving result may appear flat and dull.

 

3. Edit the Picture

The purpose we edit the picture is to emphasize the subject and sharpen the edges, producing a clear and distinctive engraving result. It does not require a lot of complex photo editing skills to achieve the effects we want. The operations we need to perform on the picture mainly include cropping, adjusting contrast and brightness, sharpening. You can use any photo editing program that includes these basic functions. Here we use the free open-source raster graphics editor, GNU Image Manipulation Program (GIMP) for demonstration. Now, let’s open the picture in the editor and get started!

 

(1) Crop the picture

Crop the picture based on your need.

   → 

 

(2) Desaturate the background

By fading the background, we can avoid background overpowering the subject. In some cases, if you don’t need the background, you can also directly remove the background.

First, we need to isolate the main subject from the background. We can do this by using the free select tool to trace the subject out.

Then, select the background, reduce its contrast and make it lighter.

 

(3) Reduce the shadows

Shadows usually cause darker burning during laser engraving. If there are too many shadows on the main subject, it may cause the final engraving product to look dirty.

Select the main subject, and then adjust its shadows and highlights. By increasing the exposure of the shadows and adding more highlights, we can get rid of some heavy shadows.

 

(4) Sharpen the subject

After adjusting the shadows and highlights, the overall color of the subject appears bright. But this is still not the final effect we want. To make a distinct engraving, we need to make the edges more clearly defined.

First, add more contrasts, to make the lines of the subject more pronounced again.

Then, sharpen the image, making the image looks crisp.

 

Finally, we get the picture suited for laser engraving. As you can see, compared with the original image, the edited one has a weakened background and a well-defined subject. Now we can save the picture and export it as a .png file. If you use other image editing programs, be careful not to compress the picture when saving it.

    → 

 

4. Start Laser Engraving

Here we come to the last step, engraving the picture on the selected materials. Depending on the laser engraving and cutting machine you use, the procedure for starting laser engraving may vary. In this step, we will use Snapmaker Luban to transform the picture into a G-code file and use Snapmaker 2.0 1.6W Laser Module to do the laser engraving job.

 

(1) Import the picture to Snapmker Luban

After you import the picture to Snapmaker Luban, you can resize and rotate it, adjust its position on the coordinate, and transform it to a greyscale image.

 

(2) Select Movement Mode

When creating the toolpath, you can select the Movement Mode, including Dot-filled Engraving and Line-filled Engraving. Dot-filled Engraving takes more time but results in a more detailed image. To pursue a better engraving quality, we use Dot-filled Engraving as the Movement Mode.

 

(3) Set Laser Power and Dwell Time

Both the Laser Power and Dwell Time directly affects the engraving result. The higher the Laser Power and the longer the Dwell Time, the darker the engraving color.

We can use the control variate method to find an optimal combination of Laser Power and Dwell Time. The engraving pattern with the darker color and without excessive charring or depression on the workpiece surface is the best result.

Finally, we set Dwell Time to 5 ms/dot, and Laser Power to 30%.

 

(4) Set Fill Interval

As we have already known, Fill Interval is the distance between the dots constituting the engraved pattern. If the Fill Interval is too large, the engraved pattern will be light-colored and might lose some details; if too small, the dots will overlap, making the engraving color too dark and the pattern indiscernib

We need to run tests to find the best fill interval. Engrave a series of squares with different dot intervals and record the interval with the clearest diagonal texture as the optimal interval.

Based on the tests, we set 0.14 mm as the Fill Interval.

 

Note： Snapmaker Luban has preset values for some material, which are tested and recommended. For more information about how to test and set work parameters, refer to the following articles: Parameter Configuration Guide: How to Set Proper Work Parameters for Laser Engraving and Cutting The Definitive Guide to Laser Engraving and Cutting with the Snapmaker

 

(5) Generate the G-code file

After configuring the work parameters, save the toolpath settings and generate a G-code file in .nc format.

 

(6) Start laser engraving

Transfer the G-code file to the laser engraving and cutting machine. Put on laser safety goggles, and we are ready to go!

For more information about how to use Snapmaker 2.0 1.6W Laser Module, refer to its Quick Start Guide, User Manual, or video tutorials.

 

Disclaimer

The methods on material selection, picture selection and editing, and laser engraving discussed herein are for reference only.

Snapmaker assumes no liability or responsibility for any property loss, personal injury, machine damage or expenses incurred by the methods on material selection, picture selection and editing, and laser engraving discussed herein or in any other means related to such methods.

 

Hello, Maker!

In the previous two episodes of Snapmaker Academy about laser, we have learned where we can get templates for laser engraving and cutting, and how we should select proper materials for laser engraving and cutting. In this episode, we are going to learn how to set parameters for laser engraving and cutting. Without further ado, let’s get started!

This article will introduce you to the work parameters for laser engraving and cutting. First, we will learn what they are and how they work. Then, we will learn how to perform parameter test to find the optimal combination of parameter values.

 

Crucial Parameters for Laser Engraving and Cutting

Laser Power

Laser Power controls the amount of energy in the laser beam. It can be set as a percentage between 0% and 100%. In laser engraving, the higher the Laser Power, the darker the engraving color. In laser cutting, a laser with higher power can cut deeper, but it will also result in seriously charred edges.

Only with sufficient laser power can we engrave a clear pattern or cut through materials. However, excessive laser power may also cause trouble. It is crucial to keep the Laser Power parameter within an appropriate range.

Work Speed/Dwell Time

Work Speed refers to the moving speed of the laser toolhead during laser engraving and cutting. When Laser Power is set to a fixed value, the faster the toolhead moves, the shorter time the laser beam stays on the workpiece, and the less laser energy the workpiece absorbs. Therefore, in laser engraving, when the other parameters remain unchanged, the higher the Work Speed, the lighter the engraving color. In laser cutting, the higher the Work Speed, the shallower the laser cuts, and the less charred the cut edges.

Dwell Time refers to the time for which a laser spot emitted by the toolhead stays on the workpiece during laser engraving and cutting. In laser engraving, when you select the Dot-filled Engraving mode, you can set Dwell Time. Both Work Speed and Dwell Time are used to control the time for which the laser with a fixed power stays on the workpiece, thereby controlling the laser energy absorbed by the workpiece. The shorter the Dwell Time, the lighter the engraving color.

Both Laser Power and Work Speed (Dwell Time) are vital to the effect of laser engraving or cutting, as they control how the workpiece is engraved and cut. When testing work parameters, we usually adjust Laser Power together with Work Speed (Dwell Time) to determine an optimal combination, as the two parameters can restrict and affect each other.

Fill Interval

Laser engraving features two modes: One is the Line-filled Engraving mode, in which the pattern is formed by engraving lines; and the other is the Dot-filled Engraving mode, in which the pattern is formed by engraving dots. Fill interval is the distance between lines or dots.

In the Line-filled Engraving mode, the Fill Interval defines the distance between the lines comprising the engraved pattern. If the Fill Interval is too large, the engraved pattern will be light-colored or even discontinuous; if too small, the lines will overlap, making the pattern too dark or blurred.

In the Dot-filled Engraving mode, which follows the similar principle as the Line-filled Engraving mode, the Fill Interval is the distance between the dots constituting the engraved pattern. If the Fill Interval is too large, the engraved pattern will be light-colored and might lose some details; if too small, the dots will overlap, making the engraving color too dark and the pattern indiscernible.

This is how the two modes differ: When you set the Fill Interval in the Line-filled Engraving mode, you only need to focus on the interval between each line and its adjacent line, but in the Dot-filled Engraving mode, you need to consider the interval between a dot and all of its surrounding dots. Therefore, the Fill Interval configuration in the Dot-filled Engraving mode is more complex, and you need to first determine the parameters including Laser Power and Work Speed, and then fine-tune Fill Interval between dots until you find a parameter range for the best engraving effect.

Number of Passes

Number of Passes is a required parameter in the Cutting Mode. To cut through a thick workpiece, multiple cuts are required on a fixed path. This parameter determines the number of cutting passes on a fixed path.

Generally, the laser beam emitted by the laser toolhead is in the shape of an inverted cone, and the focal point has the highest laser energy and cutting ability. To ensure that the focal point of each cut falls on the workpiece, the laser toolhead will lower by a certain height each time Number of Passes is increased so that the laser focal point can reach the workpiece. However, the laser toolhead cannot be lowered to a height where it is too close to the workpiece surface. Otherwise, the toolhead may bump against the workpiece. As the laser cuts deeper, the laser beam will be blocked by the workpiece on both sides, and the laser energy reaching the cutting position will taper off until it is unable to cut through the workpiece. Therefore, Number of Passes cannot be increased without limit.

How to Find the Optimal Work Parameters

To determine the optimal combination of work parameters, we have to run a certain number of laser parameter tests, and adjust the parameter values according to the working principle of laser parameters.

The Snapmaker Laser Engraving and Cutting Machine can perform laser operations in the following three modes: Line-filled Engraving mode, Dot-filled Engraving mode, and Cutting Mode. In the following section, we are going to learn how to test the work parameters under these three modes.

Line-filled Engraving Mode

In the Line-filled Engraving mode, the machine engraves lines to form a pattern. The engraving effect is mainly determined by three work parameters, namely, Fill Interval, Laser Power, and Work Speed.

Line Fill Interval Test

The thickness of a laser-engraved line is determined by the diameter of the laser spot falling on the workpiece. With accurate focusing, the diameter of the laser spot emitted by the Snapmaker 2.0 1.6W Laser Engraving and Cutting Machine is 0.20 mm, so the width of the laser-engraved line is also 0.20 mm.

Theoretically, if the engraved line is 0.20 mm thick, the lines with an interval of 0.20 mm can fitly cover the engraved surface without overlapping each other and form a complete pattern. However, in laser engraving and cutting, the effective area of the laser beam may be diffused. To avoid edge overlapping and prevent secondary engraving, a 0.05-0.10 mm buffer area is usually reserved between the lines. Therefore, a line interval of 0.25-0.30 mm is recommended.

It should be noted that when the line interval is greater than 0.30 mm, the color of the engraved pattern will theoretically become lighter, and the lines may even diverge. However, in this case, if engraved lines remain thick and greatly overlap, the focus may be inaccurate or the Laser Power may be too high. You just need to refocus or lower the Laser Power.

Click the icon below to get the test template for Fill Interval in the Line-filled Engraving mode:

 

Laser Power and Work Speed

Both Laser Power and Work Speed are variables. In parameter tests, we can assign a fixed value to one variable and fine-tune the other until we find the best engraving effect. Here, we set the Work Speed v₁ to 500 mm/s and line interval to 0.25 mm, and we make Laser Power the only variable. We then increase Laser Power stepwise to engrave a series of 10 mm × 10 mm squares on the workpiece surface.

From these squares, we select the one with the best engraving effect on the principle of "clear lines and no excessive charring", and record the power W₁ corresponding to the result.

Theoretically, the engraving area on the workpiece (S), the energy absorbed by the workpiece surface (E), Laser Power (W), the engraving time (t), and Work Speed (v) can be expressed with the following equations:

E = W * t

t = S/v

Therefore, E = S * W/v, indicating that Laser Power W is directly proportional to Work Speed v.

In the first test, we have found that when Work Speed is v₁, the power corresponding to the best engraving effect is W₁. To maintain the best engraving effect, E cannot be changed. Through the theoretical formula E = S * W/v, we can infer that if Work Speed is increased to v₂, the engraving power must be increased to W₂ in proportion so that E can remain unchanged.

However, the relationship between W and v may be affected by many other factors and is not necessarily in strict direct proportion. Therefore, after we infer the possible Laser Power corresponding to a Work Speed using the theoretical formula, we need to run more tests to ensure we can get the best engraving effect.

Click the icon below to get the test template for Laser Power and Work Speed in the Line-filled Engraving mode:

 

Dot-filled Engraving Mode

In the Dot-filled Engraving mode, a pattern is created by laser spots. The engraving effect is mainly determined by three work parameters, namely, Fill Interval, Laser Power, and Dwell Time.

Laser Power and Dwell Time

The way to test Laser Power and Dwell Time in the Dot-filled Engraving mode is similar to that in the Line-filled Engraving mode. First, we assign a fixed value to both Dwell Time and Fill Interval. Here, we set the Dwell Time t₁ to 5 ms/dot and the Fill Interval to 0.14 mm. Then we fine-tune the value of Laser Power, and we get a series of squares.

In the Dot-filled Engraving mode, the criterion for the best engraving effect is the darker color without excessive charring or depression on the workpiece surface. During the engraving process, the relationship between Dwell Time t and Laser Power W is E = W*t (E is the energy absorbed by the workpiece for each engraved dot).

In the first spot engraving test, we record the optimal Laser Power W1 corresponding to Dwell Time t₁ and calculate the optimal combination of Dwell Time and Laser Power at other Work Speeds through W₁*t₁ = W₂*t₂. Then, through further tests, the optimal parameter values are determined.

Click the icon below to get the test template for Laser Power and Dwell Time in the Dot-filled Engraving mode:

 

Dot Fill Interval Test

The difference between the Dot-filled Engraving mode and the Line-filled Engraving mode is that the former uses dots to form patterns while the latter uses lines. In the Line-filled Engraving mode, we only need to focus on the interval between the lines in the vertical direction, while the Dot-filled Engraving mode requires us to consider the interval between dots in all directions. Therefore, we first find an optimal combination of Laser Power and Dwell Time through parameter tests, and then run further tests on the Fill Interval to get the best engraving effect.

The method to test Fill Interval is to adjust the interval between dots and keep other parameters unchanged, so we can get a series of 20 mm × 20 mm squares with different dot intervals.

For these squares, the clearer the diagonal texture, the better the engraving effect. We record the interval with the clearest diagonal texture as the optimal interval.

Click the icon below to get the test template for Fill Interval in the Dot-filled Engraving mode:

 

Cutting Mode

In the Cutting Mode, a workpiece is cut by the high-energy laser beam. The cutting effect is mainly determined by three work parameters, namely, Laser Power, Work Speed, and Number of Passes.

Laser Power

In laser engraving, there is theoretically a direct proportion between Laser Power and Work Speed, which is also true for laser cutting. To maintain the same cutting effect, Work Speed needs to be increased accordingly with the increase of Laser Power. In addition, when you set Laser Power to a higher value and adjust Work Speed accordingly, you can get clearer and smoother cut edges with less charring.

Therefore, in laser cutting, we generally use 100% Laser Power, and control the laser energy by adjusting Work Speed.

Work Speed and Number of Passes

When Laser Power is determined, we need to adjust Work Speed to control the effect of laser cutting. To ensure that the workpiece can be cut through, we also need to set a proper value for Number of Passes. We can run cutting parameter tests through a matrix of Work Speed and Number of Passes. We stepwise increase values of Number of Passes and Work Speed, so that we can get a series of small squares on the workpiece, as shown in the figure below.

It can be observed that under the same Number of Passes, the higher the Work Speed, the thinner the cut gap; at the same Work Speed, the greater the Number of Passes, the thicker the cut gap. To get the best cutting effect, we should find the square with the thinnest cut gap on the premise that it is cut through.

The criterion for the best cutting effect is that the squares are cut through with the minimum Number of Passes and the highest Work Speed. If the values of multiple results are close to each other, the one with the least cut-through time is the best.

Click the icon below to get the test template for Work Speed and Number of Passes in the Cutting Mode:

 

Recommended Work Parameters for Laser Processing

After a series of tests, we have obtained the optimal parameters for engraving or cutting a variety of materials. We hope these recommended parameters can help you take laser engraving and cutting in stride. For details, see the article “The Definitive Guide to Laser Engraving and Cutting with the Snapmaker”.

 

Disclaimer

The parameter test methods and recommended parameters discussed herein are for reference only.

Snapmaker assumes no liability or responsibility for any property loss, personal injury, machine damage or expenses incurred by the parameter test methods and recommended parameters discussed herein or any other means related to such methods and parameters.

Hey there, Maker!

 

Welcome to the CNC series of Snapmaker Academy. The previous five episodes focus on the CAD and CAM processes. Now, it's time to dive into practical machining.

We already understood that CNC machining works by removing material from a solid workpiece to achieve the desired geometry. The toolpath (or G-code) instructs the cutting tool (aka bit) on how to move, while the cutting tool engages with the workpiece to produce the outcome.

Just like you wouldn't use a dagger to chop ribs, various cutting tools are designed to cut out different geometries. Choosing the right cutting tool is critical to your project's efficiency and even success. Therefore, this article aims to introduce the basics of cuttings tools and walk you through some of the most commonly used router bits.

First, let's get to know the major features used to categorize a cutting tool.

Basic Terminologies

Flutes/Teeth

Teeth refer to the cutting edges, and flutes are the grooves formed between teeth. As the bit rotates, teeth are responsible for cutting materials off, while flutes help evacuate the chips (namely removed materials) from the workpiece. Though not to be taken as the same thing, these two terms are usually interchangeable since they are always identical in number.

Number of Flutes

The number of flutes on your router bit impacts the work speed and the surface finish of your product. Having more flutes offers two main advantages. First, it adds to the strength of the bit, which means the bit can be fed into the workpiece faster and work on harder material. Secondly, bits with more flutes tend to give a better surface finish.

Bits of different numbers of flutes

However, this doesn't mean you should try to go for as many teeth as you can. To explain this, we need to introduce a new concept: chip clearance. Flutes serve as the passage for chips to evacuate, and chip clearance is the amount of space that a single flute takes up. When the number of flutes increases, chip clearance (i.e., the passage) gets smaller, hence the more difficult for the chips to be evacuated. Yet, if you can't get the chips out in time, the heat produced during cutting will build up, eventually destroy the bit and even lead to burning. This is especially the case for materials like aluminum which produces large and sticky chips. That's why you should try to find the balance when deciding the number of flutes.

Type of Flutes

There are two common types of flutes: straight and spiral.

• A straight flute is parallel to the shank of the bit, striking the surface of the material perpendicular to the rotation direction. Straight bits are stronger than spiral bits and can be used at higher speeds. On the other hand, they produce less smooth surface finish on the workpiece since such design brings more chatter. They are commonly used for slotting and cutting straight contours.

Straight flutes vs. Spiral flutes

• A spiral flute goes along the shank of the bit spirally, staying in constant contact with the material surface. Such design allows less chatter and leaves the finished surface smoother, making these kinds of bits ideal for trimming surfaces. However, spiral bits are weaker when held against straight ones and cannot cut too deep into the material or work at very high speeds.

Geometries

Shape of Tip

Router bits come in a variety of tips, each creating different shapes of cuts as they engage with the material. Some of the most common types you will find are flat, ball-nose, and chamfer.

• A flat (or square) tip got a nearly 90-degree angle between its circumference and the end surface.
• A ball-nose tip has a sphere-shaped end, as its name suggests.
• A chamfer tip is a sharp conical tip. Chamfer bits are also called V-bits for their tips looking like the letter "V".

Upcut vs. Downcut

Spiral flutes can be further divided into two categories: upcut and downcut. The differences between the two types of spirals are crucial because they determine the direction in which chips are evacuated.

The spiral flutes of an upcut bit wrap around the body of the bit clockwise, pulling chips away from the workpiece being cut. An upcut bit tends to leave a rough surface finish on the top of the workpiece and a smooth surface on the bottom.

A spiral downcut bit, however, pushes chips down as it's cutting, with the flutes wrapping around the bit counterclockwise. Conversely, a downcut bit leaves a cleaner cut on top but a fuzzy surface at the bottom.

It's worth noting that you should always use an upcut bit for plunging operations unless you know what you're doing, especially for thicker materials. The reason is when a downcut bit plunges straight down, the chips have nowhere to go but to grind against each other as the bit spins, which is going to create friction and even start a fire.

Center Cutting vs. Non-center Cutting

Router bits are either center cutting or non-center cutting. The cutting edges of a center cutting bit go all the way into the center, whereas those of a non-center cutting bit leave a hole in the center. Center cutting bits can plunge straight down into the material, while non-center cutting bits cannot.

If a non-center bit were to plunge into the material, the material engaging with the hole in the cutting edges remains uncut, which can break the bit and lead to burning. To use these bits, you need to drill a pilot hole or use ramp plunge moves. Perhaps the only good reason to buy non-center bits is they are cheaper.

Size

Basically, size determines what you can do with any given router bit. Large ones are good at cutting a lot of material, but it comes at the cost of details. Smaller bits provide higher resolution in detail, with a trade-off in strength and machining efficiency.

Overall Length

The overall length is the distance between one end of a bit to the other. Longer bits are able to reach down deeper into the material. Now, you might believe that having longer bits sounds like a safe bet since they offer more choices. Unfortunately, that's not the case.

This brings us to a concept called "stickout". Stickout refers to the distance from the end of the collet (i.e., tool holder) to the bit's tip. It's this part of the bit that works without support. The more stickout, the less rigid a tool is. If it sticks out too far, the bit is prone to be bent by the cutting force.

Cutting Length

As we can see, cutting edges (or flutes) cover only a portion of the bit. The cutting length (also called "flute length") of a bit determines how deep it can cut into the material. Note that the cutting depth should never exceed the flute length of your bit. Otherwise, chips won't be pulled out properly, and your bit could be damaged by the heat accumulated.

Shank Diameter

The shank diameter is the width of the non-cutting end of the tool. This is the diameter that will go into your collet. Common shank sizes are 3.175 mm (1/8 inch) and 6.35 mm (1/4 inch).

Cutting Diameter

This is the diameter of the cutting end of your router bit. It is often the first thing to look for when choosing a tool for your job, as it determines the resolution of cutting.

When cutting, the cutting edge will leave a circular profile in every internal corner, with a radius equal to half its diameter. Also, it is impossible to cut out features that are smaller than the cutting diameter because bits are cylinders (except for V-bits). Say, you can never have a slot that is 2 mm wide using a typical bit with a cutting diameter of 3.175 mm.

On the other hand, a bigger cutting diameter makes your bit more rigid, allowing deeper cuts. Besides, bits with a larger cutter diameter can remove more material per unit of time, which means you can do the same job faster.

Common Router Bits

There are literally tens of thousands of tool types and variations available for CNC machines. Covering every type and use is beyond the scope of this article. We will introduce the most commonly used router bits.

Before diving in, we need to clarify the differences between milling bits and drill bits. Milling bits, including end mills, face mills, and v-bits, are designed to cut with their cutting edges as they move laterally through the material. By contrast, drill bits are intended to be used for drilling holes, plunging straight down into the material.

End Mill

End mills are designed to cut with their cutting edges on the circumference of the bit, but they do have cutting edges on the end surface too. Though center-cutting end mills are capable of plunging straight down, such operations could be demanding for them and should be avoided if possible.

Flat End Mill

With a nearly 90-degree angle between its circumference and end surface, a flat end mill is going to create neat square corners at the bottom and a flat surface anywhere it passes over the top of. They are great for removing large amounts of material, widely used for everything from roughing to cutting pockets and 2D contours.

Flat end mill

Ball-nose End Mill

The circumference and the end surface of a ball-nose end mill form a rounded corner. The radius of that round corner equals the cutting radius (i.e., half of the cutting diameter). These mills excel at creating curvature or detail-rich 3D shapes like relief.

Ball-nose end mill

Since their tips are round, cutting out a perfectly flat surface is challenging for these bits because they will leave scallops on the workpiece.

Bull-nose End Mill

You can see bull-nose end mills as a transition between flat and ball-nose ones. The radius of its round corner is smaller than the cutting radius. Since they combine a flat bottom with round corners, they can create flat-bottomed pockets with rounded corners at once without changing tools.

Bull-nose end mill

Roughing End Mill

Roughing end mills have many serrations on the cutting edges to quickly break up chips, which is great for efficiently removing a large amount of material. The thing with roughing end mills is that they will leave a poor surface finish with corncob-looking tracks on your workpiece, and that's why they are often referred to as corncob end mills. Hence, roughing end mills are for roughing only.

Roughing end mill

Face Mill

Face mills are designed to cut with their cutting edges on the end surface of the bit. They often come with multiple cutting edges that are replaceable, which allows removing more materials at higher speeds. These kinds of mills need powerful spindles to push them.  These mills are mostly used for creating a large and smooth flat face on the surface of a plate or bar workpiece. 

Face mill

V-bit

V-bit, also known as chamfer mills, are used for chamfering, deburring edges, and letter engraving. They are not so good at cutting profiles or carving out pockets since they'll leave a sloped surface on the workpiece.

V-bits are available in many sizes and angles, although 90, 60, and 30 degrees are most common. A smaller angle often comes with a smaller cutting diameter, supporting shallower cuts while retaining more details. A bigger angle allows wider cutting diameter and deeper cuts.

V-bits in different sizes

Drill Bit

Drill bits are designed to bore straight down into the material with their pointed tip. Unlike milling bits, their flutes only function as the passage for chips to be pulled out. They are often used for pre-drilling holes for screws.

Drill bit

Summary & Next Up

This article introduces some of the most commonly used router bits on top of explaining the basic terminologies used to describe cutting tools. And that is the foundation for us to look into setting parameters for cutting jobs in the future. We hope it could be helpful for you!

In the next episode, we are going to introduce some of the most common features of a model that you might encounter and then exemplify how to choose the right router bits for a CNC project. Please stay tuned!

Hey there, Maker!

 

This article breaks into two parts. In part 1, we learned the concepts of CAD, CAM, post processor, and firmware, as well as the CAM workflow of Fusion 360 in detail.

In this part, we will continue with other CAD/CAM software picks: FreeCAD, Aspire, and Carveco Maker (formerly ArtCAM). We will also briefly introduce two easy-to-use CAM software picks: Snapmaker Luban and MeshCAM.

CAM Software

 This article only focuses on the CAM features of the software introduced. To learn more about their CAD-related features and highlights, see CAD for CNC: Eight 3D Modeling Software Picks to Visualize Your Ideas.

FreeCAD

FreeCAD is a free 3D modeling software with a strong suit for designing solid models. Once a model has been created, you can switch to Path Workbench to generate the toolpath and G-code.

 If you're using FreeCAD to design models for the first time, you need to download and import the post and tool library to ensure that the G-code that is to be generated can be successfully exported to Snapmaker CNC Carving Module for further processing. 

• To import the post, copy the .py file to the Mod\Path\PathScripts\post folder in the installation directory of FreeCAD.
• To import the tool library in the latest FreeCAD 0.19, perform the following steps:

1. Click Edit > Preferences > Path > Job Preferences > Tools. Select Use Legacy Tools, and click OK.
2. Switch to Path workbench. Click  > Import. Select the .json file in the FreeCAD folder of the post and tool library and click Open.

Import a tool library in FreeCAD - 1

Import a tool library in FreeCAD - 2

Click  to set up the basic configurations of your carving job. In the Output tab of the Job Edit panel, you can enter a name and extension for the G-code file to be generated and select the post in the Processor bar. In the Setup tab, you can define the dimensions of the stock in relation to the model and the location of work origin. In the Tools tab, you can select the tool for your carving job.

 The extension for G-code files that Snapmaker CNC Carving Module can recognize is .cnc.

After performing these basic configurations, you can select different features of the model in the tree diagram on the left and apply different machining strategies to generate separate toolpaths for each of them. For example, for the outer profile of your model, select a strategy that can quickly cut through the material, whereas for sunken areas, opt for a strategy that can efficiently remove the material. While generating toolpaths, FreeCAD allows you to preview how the tool moves and what the finished product looks like, so that you can make adjustments in real time.

Simulation in FreeCAD

If you know your way around G-code, you can click  to inspect the G-code content of a path and view or directly edit the G-code in the text box that appears. Once everything is set, click  to post process the selected job and generate the G-code specific to Snapmaker CNC Carving Module.

Here are two great tutorial videos that you can check out: FreeCAD - The Powerful Path Workbench for CNC Machining and G-code and Ultimate Free CNC CAM tutorial with FreeCAD.

Aspire

Aspire is a reputable wood relief design software with powerful CAM features.

With Aspire, the first step of modeling is setting the coordinate system and the stock parameters. When creating a project, you need to specify Job Type, Job Size, work origin (i.e., XY Datum Position, and Z Zero Position), and Orientation in the Job Setup pane first. Aspire supports four-axis CNC carving. To work with Snapmaker Rotary Module, just select Rotary in Job Type.

 If you're using Aspire for the first time, you need to download and import the post and tool library to ensure that the G-code can be successfully exported to Snapmaker CNC Carving Module for further processing.

• To import the post, open Aspire, click Toolpaths > Install Post Processor..., and click the .pp file in the Aspire folder of the post and tool library. (There are two files with the .pp extension in the folder, one for three-axis machining and the other for four-axis machining. You can import only one post at a time.)

Import a post in Aspire

• To import the tool library, open Aspire, click Toolpaths > Tool Database, and click Import. Then, open the Aspire folder of the post and tool library and select the .tool file.
  

Import a tool library in Aspire - 1

Import a tool library in Aspire - 2

After you finish modeling, click on the top left to proceed to set up toolpaths by configuring the parameters in the Toolpaths pane that appears on the right. You can modify the previously set stock parameters in the Material Setup panel at the top.

Next, you get to choose appropriate machining strategies for different features of the model. In relief carving, for example, we apply rough machining to carve out the general outline and then use finish machining for the details. In these two rounds of machining, different tools and machining strategies are required, which are to be generated as corresponding toolpaths. In the Toolpaths pane, click Select to pop up the Tool Database window, where you can select the tool to use. Click Edit to set machining parameters such as spindle speed, feed rate, and stepover. When you’re done with setting the parameters, click Calculate to generate toolpaths.

After the toolpath is generated, click Preview Selected Toolpath to visualize how the tool moves and what the finished product looks like. Should you need to adjust the toolpath, the operation is pretty easy. Double click the toolpath on the right, and the parameter setting window then appears.

Simulation in Aspire

When all is set, click  to generate the G-code. The post that you have imported earlier will appear in the Post Processor bar. Click Save Toolpath(s), and the G-code customized for Snapmaker CNC Carving Module will be generated.

As a top choice for CNC relief design, Aspire comes with well-made official training videos. You can also find many videos made by users on YouTube and other platforms, such as Vectric 3D Carving & Toolpath Tutorial for Vcarve & Aspire and Basic Guide to CNC with Vectric Vcarve Pro / Aspire Profile Toolpath.

Carveco Maker

Our last guest is Carveco Maker created by the team behind ArtCAM. If you're familiar with ArtCAM, you will quickly pick up on Carveco Maker, as it draws heavily from its predecessor.

In Carveco Maker, two separate steps are required to set the stock dimensions. The width and height are defined when you create a new project, whereas stock thickness is defined in the window where you configure toolpath parameters. By default, the work origin is the center of the stock. You can modify it by clicking Model > Set Position (P) in the top navigation bar. After you finish modeling, click Toolpaths in the tree list on the right to start setting the machining strategies and toolpath parameters.

 If you're using Carveco Maker for the first time, you need to download and import the post and tool library to ensure that the G-code can be successfully exported to Snapmaker CNC Carving Module for further processing.

• To import the post, copy the .con file in the ArtCAM folder of the post and tool library to the postp folder in the installation directory of Carveco Maker.
• To import the tool library, after you finish modeling in Carveco Maker, click Toolpaths in the Project panel and then click in the Toolpath Operations panel to enter Tool Database. In the pop-up window, click Import.., select the .tdb file in the ArtCAM folder of the post and tool library, and click Open.
  

As with the previous software, different machining strategies are needed for different features of the model in Carveco Maker. After you select a feature, choose the way you want it to be machined by clicking the corresponding button on the Toolpaths pane to the right. In the pop-up window, you can select a tool and set its machining parameters, such as feed rate, stepover, and cutting depths. As mentioned previously, this window is also the place where you can define stock thickness. After finishing setting, you can run a simulation to view the processing results.

Simulation in Carveco Maker

After you finish configuring toolpaths, click Toolpaths in the tree list of the Project panel. Then, in the Toolpath Operations panel below, click  to save your toolpath. In the pop-up window, select the post processing method that has been imported in the drop-down list of Machine file format, and click Save to export the G-code. Now, we can send the G-code to the CNC machine for carving and simply wait for the finished product.

The Carveco Maker team has already made a series of official training videos, such as Carveco Maker - Designing A Plaque (part one) and Carveco Maker - Machining A Plaque (part two), covering the most common basic operations. The two videos here use the example of making a plaque to demonstrate the entire procedure, from designing a sketch to setting the toolpaths and exporting the G-code. Also, ArtCAM users have made a large amount of tutorials resources that are helpful for using Carveco Maker, as the two pieces of software practically share the same working logic.

Snapmaker Luban & MeshCAM

That's all for our introduction to CAD/CAM software picks. Sometimes, we have already finished the model design and simply want to turn it into toolpaths. This is where software dedicated to CAM comes in. So, let's take a look at two CAM software picks: Snapmaker Luban and MeshCAM.

Snapmaker Luban is free and open-source CAM software developed by the Snapmaker team. Tailored specifically to Snapmaker 3-in-1 3D Printer, it is designed with user-friendliness in mind around three major functions: 3D printing, laser engraving and cutting, and CNC carving. Needless to say, the CAM features of Snapmaker Luban match Snapmaker hardware with perfection. The toolpaths and G-code that it generates can be directly used by Snapmaker CNC Carving Module. In addition, it also supports the preview of tool movements and the finished product. If you simply want to carve out the finished product based on an existing model file, Snapmaker Luban is without doubt one of the best candidates.

MeshCAM is one of the most popular CAM software on the market, with excellent ease of use as its main highlight. Thanks to its straightforward workflow and simple operations, even those new to the world of CNC without machining knowledge can easily master it. Automatic toolpath configuration is one of the things that make MeshCAM great. Simply choose the tools and the desired quality level, and MeshCAM will automatically calculate the appropriate parameters. The built-in post processor of MeshCAM does not support Marlin yet. Some additional steps are required to translate the G-code into a format recognizable for Snapmaker.

Summary

The CNC workflow begins with CAD, where imaginations are transformed into designs. Next, CAM connects design and manufacturing by transforming designs into toolpaths for CNC carving machines. The first three articles of our CNC series focused on CAD and introduced eight CAD modeling software picks along with 12 recommended websites for modeling resources. In the fourth and fifth articles, we moved forward along the CNC workflow, clarified some key concepts in CAM, including post processor, firmware, and CAM workflow, and presented four integrated CAD/CAM software picks with their respective work process. Now, we have learned the complete process from CAD to CAM. We hope that these articles can help you get started with CAD and CAM for CNC!

Snapmaker Academy will continue to offer more CNC carving resources and information. So stay tuned! If you are interested in any topic, please feel free to let us know by leaving a message in our community or sending an email to support@snapmaker.com.

Disclaimer

Snapmaker recommends the software and videos to you in no particular order and for resource-sharing purposes only. Snapmaker does not in any way endorse, control, or assume responsibility for the content, views hosted on, and services provided by the developers of the software or individuals.

Hey there, Maker!

 

Welcome to Snapmaker Academy! This is the fourth episode of our CNC series. The three previous episodes focused on CAD and introduced some practical modeling software and websites of modeling resources. Now, let's turn to CAM and check out four CAM software picks suitable for CNC carving.

Photo by Fakurian Design on Unsplash

Before jumping right into CAM software, let's go through some basic concepts. First of all, what are CAD and CAM?

CAD vs. CAM

We already know that, in the CNC workflow, three steps are required to turn an idea into a finished product. First, obtain the model file. Second, transform the model file into commands that CNC machines can execute. Third, import the commands into a CNC machine to start carving till we obtain the finished product.

Computer-aided Design (CAD) refers to the first step in this workflow. It covers aspects related to model designing, such as conceptualization, detailing, modification, etc. Computer-aided Manufacturing (CAM), on the other hand, corresponds to the second step, through which models are transformed into commands (toolpaths and the corresponding G-code) that tell the CNC machines what to do. Usually, it also includes operations like simulation and error check to minimize the risk of going wrong.

For example, you want to build a toy car. First, you need to turn the imaginary toy car in your head into a model file, which is essentially a collection of geometrical data. This step is called CAD. Next, you use software to transform the model file into G-code. The toolpaths in the G-code tells the machine what to do in order to carve the geometric forms depicted by the model, such as round corners, bosses, and grooves of the toy car. With simulation and error check, you can preview the path of the tool on the material surface and judge if the carving will go smoothly. This step is called CAM.

Photo by Tool., Inc on Unsplash

In a nutshell, with CAD, we transform ideas into designs, and with CAM, we manufacture real products based on the designs. The two processes complement each other and are equally indispensable.

Post Processor & Firmware

Now, it's time to move on to two new terms: post processor and firmware.

As mentioned before, your design can become G-code thanks to CAM software. But in order to successfully carve out the finished product, a crucial step is to make sure that your machine can effectively recognize the G-code output by the CAM software.

You can think of G-code as a collection of different "dialects". Post processors translate the dialects into the one that your specific CNC carver can understand and execute. The file that post processors use for such translation is called a "post". A post processor can be either stand-alone software or integrated into CAM software.

Firmware is a special kind of software that is embedded in hardware, resembling the operating system of your computer. For 3D printers, firmware is responsible for transforming G-code into control commands that tell your CNC carver what to do. The firmware of your CNC carver determines the type of G-code it can read. This means that you need to know what language your machine speaks (i.e., its firmware type) first and then select a translator (i.e., a post processor) that works for it.

Products made with Snapmaker CNC Carving Module

Marlin is one of the most popular 3D printing firmware. Other widely-used firmware includes GRBL and Klipper. The firmware of Snapmaker 3-in-1 3D Printer is developed based on Marlin. Currently, we provide posts for ArtCAM, Aspire, FreeCAD, and Fusion 360. After downloading the file, simply import it to the software to generate the correct G-code for your Snapmaker CNC Carving Module.

 To learn more about Marlin, see What is Marlin?.

CAM Workflow

Before delving into each CAM software, let's go through the overall workflow of CAM briefly. This can help us better understand the logic of using each software. A typical CAM workflow consists of the following six steps:

1. Import the model to CAM software;
2. Set the coordinate system and define the position and work origin of the stock (i.e., the material to be carved);
3. Specify stock parameters, such as its dimension and orientation;
4. Select the machining method (for example, three-axis machining or four-axis machining) and the tool (for example, flat end mill or ball end mill) being used;
5. Preview the toolpath in simulation to visualize in advance how the tool moves and what the finished product looks like;
6. Perform post processing and export the G-code.

Now that we have understood the role of CAM in the CNC workflow and the CAM workflow, it's finally time to get down to business. Let's look at some excellent CAM software!

CAM Software

CAD and CAM are two independent procedures, and a lot of software focuses on one of the two. However, due to our pursuit of convenience, more and more software now integrates both CAD and CAM features to enable an all-in-one design process.

One big advantage of this type of CAD/CAM software is the elimination of data format conversion, which occurs when you import a model file from CAD software to CAM software. CAD/CAM software works with the same data files from sketch design to the generation of G-code. What's more, it is easier to edit model files because you do not need to switch between different software. This article will introduce four pieces of CAD/CAM software with a focus on CAM: Fusion 360, FreeCAD, Aspire, and Carveco Maker (formerly ArtCAM).

To learn more about their CAD-related features and highlights, see CAD for CNC: Eight 3D Modeling Software Picks to Visualize Your Ideas.

Fusion 360

The CAD part ends as you finish the sketch design in the Design Workspace of Fusion 360. You can then click to switch to Manufacture Workspace for performing CAM operations.

 If you're using Fusion 360 to design models for the first time, you need to download the post and tool library first and then import them to Fusion 360. The video How to Model & Setup CAM for CNC in Fusion 360 shows you how to do it. As mentioned before, the post ensures that Snapmaker CNC Carving Module can understand the G-code that will be generated by Fusion 360. The tool library tells the software which type of tool we intend to use so that the software can calculate the corresponding toolpath.

Preparations are now done. We can proceed to the manufacturing process! The first step is setup. In this step, we define the coordinate system and the work origin for the stock. By specifying how the stock is placed on the work platform of your CNC carver, this step associates the virtual coordinates in the software with the actual ones in manufacturing.

Now, the software knows the data of the model file, the size and orientation of the stock, and the tool type. It's got everything needed to calculate and generate the toolpath that instructs the tool on how to move. In addition, Fusion 360 supports real-time simulation. It shows the path of the tool in animation to let us visualize the final machining effect in advance. We can edit the toolpath while conducting simulations to optimize the carving result.

Simulation in Fusion 360

With the post imported previously, we can now directly convert the toolpath into the G-code specific to our Snapmaker CNC Carving Module. Then, we import the G-code to the machine and start carving. Now we just wait for the finished product.

Fusion 360 has a great number of users. Its CAM tutorial videos are also easy to find. There are official videos like Fusion 360 CAM Basics and videos made by users like How To Get Started with CAM Within Fusion 360 — Tutorial.

Next Up

Limited by length, this article breaks into two parts, and this is the first part. In the next part, we will continue with other CAD/CAM software: FreeCAD, Aspire, and Carveco Maker (formerly ArtCAM). We will also briefly introduce two pieces of CAM software: Snapmaker Luban and MeshCAM. So, make sure to stay tuned!

Disclaimer

Snapmaker recommends the software and videos to you in no particular order and for resource-sharing purposes only. Snapmaker does not in any way endorse, control, or assume responsibility for the content, views hosted on, and services provided by the developers of the software or individuals.

Hey there, Maker!

 

This article breaks into two parts. In Part 1, we introduced four pieces of artistic relief modeling software suitable for creating relief models that allow for more free-formed shapes and typically serve visual expression.

In addition to decorative relief, CNC carving is also commonly used to manufacture products with a more regular form or involving assembly, such as phone stands and toy cars. Strict with dimensions, these products should better be designed as solid models of higher accuracy to ensure smooth output to CNC machines. This is where we need to use industrial design modeling software.

Photo by Fakurian Design on Unsplash

In this article, we will take a look at the best of the best in industrial design modeling software for CNC solid modeling—Fusion 360, FreeCAD, SolidWorks, and SketchUp.

Industrial Design

Fusion 360

Price: $60/month, $495/year, or $1,335/3 years (By subscription)

Supported System: Windows, macOS

Highlights: One-stop work platform, Intuitive interface, Cloud storage, Massive supporting resources, One-year free trial

When it comes to solid modeling, we have to mention Autodesk Fusion 360, one of the top modeling software picks in recent years, especially all the rage among makers.

Fusion 360 boasts three benefits. First, it is not only a piece of modeling software, but also a versatile work platform providing a complete suite of tools from model design to manufacturing. It is easy for DIY hobbyists to learn.

Second, it connects modeling with manufacturing. Photorealistic rendering, product simulation testing, and a set of built-in CAM tools to directly generate toolpath and G-code enable a seamless transition from design to manufacturing in the CNC workflow.

Third, the software highlights excellent ease of use on top of its powerful features. Its intuitive interface is user-friendly and easy to get started with. Many users find Fusion 360 more productive than other equivalents when completing the same model design.

Fusion 360 has more to offer. It is one of the first CAD work platforms to support cloud storage. Users can synchronize personal files across multiple platforms and easily retrieve the change records, and collaborate with each other in real time.

In addition, thanks to the huge user base, related instructional videos are everywhere on YouTube, and third-party plug-ins and other resources are also abundant. Snapmaker Academy has previously produced a Fusion 360 tutorial on how to create a model, set up toolpaths, and use the Snapmaker 3-in-1 3D Printer to carve out a finished product.

Fusion 360 CAD & CAM Tutorial Video 

Of course, as a typical Autodesk product, Fusion 360 is available in Education and Personal editions, both of which are free for one year.

FreeCAD

Price: Permanently free

Supported System: Windows, macOS, Linux

Highlights: Open source, Cross-platform, Parametric modeling, Integrated CAM tools

FreeCAD is a piece of free and open-source 3D modeling software used to design solid models of any size for personal projects and fields such as industrial product design and architectural engineering.

The software is designed for parametric modeling, which means the shape of an object is defined by parameters, and all shape changes are recorded to maintain a precise modeling history. You can modify any feature of the models by changing the corresponding parameters. Moreover, changes to individual features can be synchronized to the final model by simply setting the constraints, eliminating the need for repeated operations.

FreeCAD is separated into workbenches. A workbench is a collection of tools suited for a specific task. The Part Workbench and the Part Design Workbench are commonly used in CNC carving. You can produce any geometry by building multiple 3D parts and connecting or assembling them.

FreeCAD can read and write files in various formats, including STEP, IGES, OBJ, STL, DWG, DXF, SVG, IFC, and DAE, basically covering all major 3D models and image files. Highly customizable and extensible, it can be augmented with various plug-ins to support more file formats. Tutorials on the software are easily accessible, such as How to model an easy part for CNC machining in FreeCAD.

In addition, it also provides CAM tools to help you link your design up with manufacturing. Once a model has been created, you can switch to the Path Workbench to generate toolpaths and G-code.

SolidWorks

Price: $3,995/license + $1,295/year by subscription (Standard version)

Supported System: Windows

Highlights: Parametric modeling, Powerful functionality, Easy to learn and use, Cloud storage, Integrated CAM tools

SolidWorks, a piece of CAD software developed by Dassault Systemes, is one of the top solid modeling software picks at present. Dassault Systemes provides 3D design and product development solutions in a wide range of fields such as aerospace, machinery and electronics, and energy materials. Boeing 777—the world's first 100% digitally designed jetliner—was modeled using the company's modeling software.

Like FreeCAD, SolidWorks uses parametric modeling to help you visualize your design precisely, and changes to individual features can be updated in real time to the final model. The modeling method is much the same as in FreeCAD, i.e., creating surfaces and then truncating or stretching the surfaces to get the model you want.

SolidWorks also provides rendering, simulation, manufacturability check, and CAM tools to help users reduce potential errors in the design process and achieve "manufacture-oriented design." In terms of data management, the software supports cloud storage and real-time collaboration. It boasts excellent expandability and compatibility, as it can be used with many plug-ins and other modeling software.

Among the four pieces of solid modeling software, SolidWorks provides the most powerful and comprehensive functions, allowing you to design complex parts and assemblies easily, and satisfy advanced modeling needs. Moreover, it is easy to use, intuitive, and quick to get started. As the software has millions of users, it is easy to access supporting resources from their official community, YouTube channel, and Reddit community. Technical support is covered in the annual subscription fee included in the price of the software.

SketchUp

Price: Free version and three paid versions available

Supported System: Windows and macOS for Desktop version and all operating systems for Web version

Highlights: Easy to use, Cloud storage, Web client available, Free model library

SketchUp is a piece of easy-to-use 3D design software, dubbed as the "pencil" to generate digital designs, which is widely used in interior and architectural design. If you are not sure which modeling software is right for you, SketchUp is a good choice to start with.

To build a model, you simply create 2D shapes by drawing lines and then extrude them into 3D objects. This is the most common method for architectural modeling and can also be used for CNC solid modeling of regular parts. You can also use SketchUp to break down the 3D structure to be assembled into vector graphics for CNC cutting. However, it does not provide CAM tools, and you need to install plug-ins or use other CAM software to generate toolpaths and G-code.

SketchUp is available in one free version and three paid versions. The free version is web-based, so it cannot be used offline. SketchUp Shop is the cheapest of the three paid versions and it is also web-based, so it is suitable for DIY modeling. The other two versions—Pro and Studio—can run on both web and desktop.

SketchUp supports a wealth of plug-ins and offers mobile apps for iOS and Android devices, allowing you to view your 3D models on your mobile device at any time. Its 3D Warehouse is a free online open library where anyone can upload or download materials and models. A lot of official tutorial videos are available, such as Top Tips for Fabrication and Prepping Woodworking Projects for LayOut in SketchUp. SketchUp also has an active community forum, which is worth visiting.

Summary

In this article, we introduced four pieces of industrial design software for solid modeling, namely Fusion 360, FreeCAD, SolidWorks, and SketchUp. The former three provide built-in CAM tools. Fusion 360 is known for its one-stop work platform and intuitive interface. FreeCAD is a piece of free open source software that can run on all platforms and support various extensions. SolidWorks is a powerful tool that can meet advanced modeling needs. SketchUp is the easiest to use and offers a free version.

Snapmaker Academy will continue to offer more CNC carving resources and information. So stay tuned! If you are interested in any topic, please feel free to let us know by leaving a message in our community or sending an email to support@snapmaker.com.

Disclaimer

Snapmaker recommends the software and videos to you in no particular order and for resource-sharing purposes only.

Snapmaker does not in any way endorse, control, or assume responsibility for the content, views hosted on, and services provided by the developers of the software or individuals.

Hey there, Maker!

 

In the previous article, Going from Art to Part: Models, Designs and Videos for CNC Carving, we explained that model files are the first step in the workflow of CNC carving and introduced several websites that offer ready models. But, what if you're looking to turn your unique ideas into reality?

A relief carving of your cat, a wooden tray sized to fit snugly into your corner cabinet, a spectacle frame tailored to your face shape ... If you've ever thought of making something like that, now's the time to take a step further.

New to 3D modeling or not sure how to choose modeling software? Snapmaker Academy is here to help! In this article, we will walk you through eight practical CNC modeling software picks for creating your own 3D models from scratch.

Photo by Fakurian Design on Unsplash

It's worth noting that we're touching on modeling software for CNC carving purposes only and do not intend to involve detailed software tutorials.

How to choose CNC modeling software?

The thing is that the dozens of modeling software on the market often come with distinctive operating logic and functional features. Considering the cost of learning, it's definitely wise to do your homework in choosing the right one. Here are some key factors worth considering:

• Purpose of Use

  
  The software you should use when designing something to be CNC machined depends greatly on what you are trying to make. For beginners, powerful or comprehensive functions may not be necessary. On the contrary, advanced functions can be intimidating until you become proficient.

• Function & Feature
  The usage of 3D models determines how they should be designed. That's why modeling software varies in function, feature, and expandability for specific fields.

• Price
  The vast majority of modeling software is charged with prices ranging from a few hundred dollars to several thousand dollars. Before placing your order, make sure you understand what is included in the service.

• Ease of Use
  The ease of use relates directly to the cost of learning the software. A helpful reference is how intuitive the interface is. Shortcuts can also be a time-saver when making repetitive operations. 

• Support Resources
  Support resources include official technical support, user communities, and relevant UGC. These resources are the channels you can resort to when encountering a problem. The larger the user base, the stronger the user community, which is especially important for beginners. Having the guidance of someone who has been there before can be sheer bliss when you're scratching your head over a particular feature.

• Trial Availability
  At the end of the day, one trial outclasses ten introductory articles in interpreting how the software works. Given the high pricing of most modeling software, an available trial version is probably the greatest virtue.

CNC Modeling Software

Solid Modeling VS Surface Modeling

First, notice that there is a fundamental difference between 3D models used for different purposes. For industries like machinery and mold manufacturing, 3D models require high dimensional accuracy and must form a closed space, so we call them solid models. For industries such as film and games, however, surface models are commonly used, which focus more on an object's external. They allow for more free-formed shapes and do not necessarily make up a closed space. Such models typically serve visual expression only, including animation character design, product display videos, etc.

Closed Space VS Open Space

An imperfect analogy would be a comparison between engineering drawings and art paintings: while one corresponds to real objects and must be precise to the length of each line and the size of each angle, the other is visually oriented and thus can go wild to display structures that cannot exist in reality.

Actual Structure VS Surreal Structure

（Photo by Autodesk Fusion 360 on YouTube & 8385 on pixabay）

Accordingly, 3D modeling software can be divided into three categories based on modeling mechanism: solid modeling, surface modeling, and solid + surface modeling. In CNC carving, surface modeling is appropriate for creating ornamental reliefs or parts with lots of irregularly curved surfaces. Instead, products involving complex assembly or parts consisting of regular shapes like rectangles, round holes and straight lines are suggested to be designed as solid models.

Next, let's get to the point — modeling software for CNC carving. Note that the following software may support both kinds of modeling but is here divided into two categories — artistic relief and industrial design — based on the modeling mechanism it is known for.

Artistic Relief

Aspire

Price: $1,995  (Perpetual for a specific version, including free minor updates)

Supported System: Windows

Highlights: Relief design, 2D to 3D, 4-axis CNC carving, Integrated  CAM

Aspire is a one-stop CNC software solution developed by Vectric. Featuring relief design, it allows simple and quick conversion from 2D images to 3D relief models. Here's how it works: after importing a 2D image, the software assigns a height difference to the image based on the shade of color to create a 3D relief model. The darker the color, the smaller the corresponding Z-axis height value, and the deeper the carving. For this type of conversion, a grayscale image works best. You can also start with a sketch and expand it into a 3D model step by step by operating manually.

Aspire offers a set of handy tools and a rich library of resources for relief models. You can use filters to remove the noise in the image to create a smoother surface, or manually increase the Z-axis carving depth to further spotlight its three-dimensionality. What's more, the software comes with hundreds of free 2D graphics and 3D relief models to add to your creations.

Support for 4-axis CNC carving is another bonus. You can either design your own 4-axis models or import third-party models. Aspire's rotary job setup and auto-wrapped simulation allow you to visualize your job. Combined with Snapmaker Rotary Module, you're ready to create in a new dimension.

Cases made with Snapmaker Rotary Module

After modeling, the next step is to turn your model into commands that will instruct your CNC machine on how to move, which is also within the cover of Aspire. Aspire is capable of calculating 3D roughing and finishing toolpaths to accurately carve out your model, saving the trouble of using another CAM (computer-aided machining) software.

It's recommended to try out the built-in cases in the trial edition before purchasing. You can find tutorial videos for the cases on their official website. There are also many useful videos made by Aspire users, such as the one by Roger Webb, demonstrating the whole process of making a relief plaque from importing a grayscale image to setting toolpaths.

 

Carveco Maker

Price: $15/month or $180/year (By subscription)

Supported System: Windows

Highlights: Diverse relief editing tools, Broad range of supported file types, Integrated CAM

You may not have heard of Carveco, but you're probably familiar with ArtCAM, one of the oldest software devoted to CNC. In fact, ArtCAM is the predecessor of Carveco. The software was acquired by Autodesk and then discontinued in 2018; that's when Carveco Ltd. was formed with the purpose of delivering continuity of access and service of ArtCAM. Carveco Maker is the elementary variant of the Carveco software range.

Just like ArtCAM, Carveco Maker is powerful and easy to use, making it popular among woodworkers, sculptors and makers. Besides the regular 2D sketch design and 3D modeling tools, it also includes multiple features customized for relief models, such as conversion from grayscale or vector image to relief, embossing STL model to relief, one-click smoothing of relief, and more. You get to control the final presentation and fineness of the finished product at your own pace. Its relief clipart library contains more than 600 exquisite relief models, all free to use in your CNC projects.

Carveco Maker's Relief Clipart Library

Carveco Maker works easily with different types of graphics, 3D models, and CAD (computer-aided design) files. Integrated CAM is also one of its strong suits, enabling choices over machining strategies, tool configuration, toolpath generation, and real-time simulation of the final look of your design.

The Carveco team has produced a series of well-made instructional videos covering key tools and features such as Reliefs from Images. In addition, ArtCAM's existing large user base and tutorial videos are also available resources for Carveco Maker since the two pieces of software are basically the same. Carveco does not offer a trial version but a 14-day money back guarantee on the software is available.

 

ZBrush

Price: $39.95/month, $179.9/6 months, or $895/perpetual

Supported System: Windows, macOS

Highlights: Digital sculpting, Modeling with brushes, Intuitive operation

ZBrush is a leading software package in digital sculpting software, endeared to film studios, game developers, and illustrators globally. One of the major games made with ZBrush is Assassin's Creed. As the name suggests, digital sculpting is like sculpting some digitized clay through manipulating geometric shapes by pushing, pinching, chiseling and slicing with brushes. Compared to traditional 3D modeling, its operating logic is far more intuitive, reproducing the natural feeling of working with a real-life object.

It is ideal for creating detailed surface models with sophisticated and irregular shapes, powerful in presenting realistic shadows, textures, and creases.

When used for CNC modeling, ZBrush is competent in both creating 3D models from scratch and collaborating with other modeling software to add more details to your relief models, such as softening joints, adjusting partial height difference, adding textures, etc. The software is also great in real-time rendering that provides instant feedback. However, to generate toolpaths and G-codes, you need to use plug-ins or import your model into CAM software.

Plentiful sculpting brushes in ZBrush

Thanks to its intuitive logic, ZBrush is easy to get started, and tutorial videos abound. Its trial version has no restriction on features, which lasts 30 days.

Blender

Price: Free

Supported System: Windows, macOS, Linux

Highlights: Open source, Cross-platform, Free interface layout, Integrated digital sculpting

Blender is open source software for all platforms, providing 3D creation pipelines from modeling, rigging, animation, simulation, rendering, to video editing. As the only mainstream modeling software that is free for life, it is a public project hosted by the Blender Foundation, with the mission to bring 3D technology as tools in the hands of artists everywhere in the world.

Beyond polygon modeling, Blender also integrates digital sculpting, empowering fast and free detailing using brushes. Though not comparable to ZBrush in this regard, it is qualified. As with ZBrush, the generation of toolpaths and G-code requires additional CAM plug-ins or software since it does not specialize in CNC.

Sculpting brushes in Blender

A typical workflow in CNC relief modeling is to import a 2D image, trace the profile with polygons, expand it into a 3D model by operations like stretching, and then smooth the edges and corners with subdivision tools, including sculpting brushes. You can find many related videos on YouTube, such as Decoration Modeling in Blender 2.9 Part 1.

Being free and open source does not equate to a lack of support resources, at least not with Blender. Donations from users, developers, and companies keep the foundation and their official technical team running. Also, Blender's growing community is very helpful and ready to come to your aid when in trouble.

Summary & Next Up

This article introduces four pieces of artistic relief modeling software: Aspire and Carveco Maker, which specialize in CNC and excel at relief modeling with CAM tools included; and ZBrush and Blender, which allow users to create or optimize relief models through digital sculpting.

Limited by length, this article breaks into two parts and this is the 1^st part. In the next part, we will introduce Fusion 360, FreeCAD, SolidWorks, and SketchUp for solid modeling.

Disclaimer

Snapmaker recommends the software and videos to you in no particular order and for resource-sharing purposes only.

Snapmaker does not in any way endorse, control, or assume responsibility for the content, views hosted on, and services provided by the developers of the software or individuals.

Hey there, Maker!

 

You probably already know that makers' world is full of possibilities. On top of that, as the owner of the Snapmaker 3-in-1 3D Printer, with its three interchangeable functions – 3D printing, laser engraving and cutting, and CNC carving – you're empowered with more than one key to unlock the door from imagination to reality.

So, what do you want to create with your Snapmaker CNC Module?

Here are 11 resources websites that will inspire you and provide access to model files, complemented by a series of tutorial videos. Hopefully, this article will help you in taking the first stride.

To begin with, let's go through some basic concepts of CNC machining.

What is CNC machining?

CNC stands for "Computer Numerical Control". CNC machining is a common subtractive manufacturing technology. The process involves removing material from a solid workpiece with cutting tools to achieve the desired shape. Compared to 3D printing, aka additive manufacturing, CNC machining is fundamentally different since it chips material off a blank workpiece instead of adding material to build a part.

Cases made with Snapmaker CNC Module & Rotary Module

What can you do with a CNC machine?

CNC machining can work with a wide range of materials, including plastic, wood, jade, and metal. Technically, you can even build a house through CNC machining with quite some assembling, not to mention toy cars, ukulele, PCB…

Next, let's look at the workflow of CNC carving. Typically, it takes three steps to turn an idea into a finished product:

1. Obtain a model, either by modeling yourself or downloading from model repositories.
2. Turn the model file into a G-code using CAM software (such as Snapmaker Luban and Fusion 360). The G-code will instruct the machine on how to move.
3. Export the G-code to your CNC machine. Start carving on your machine and then wait for your job to be done.

Now that you've recognized what a CNC machine can do and how it works, let's get down to the gist. In the following CNC resources websites, you can indulge in inspiring ideas from all over the world or directly download model files and carve them out.

 

CNC Resources Websites

 On the 3D model files provided in the following websites, except for those specified with compatibility of CNC machines, take care in identifying whether a particular model is suitable for CNC carving.

 

Thingiverse

Being one of the world's largest and most active 3D model file repositories, Thingiverse boasts three million users and over two million models. From regular household items, ACG character figures to mind-blowing gadgets, there's something for everyone. While models for 3D printing predominate, it's not hard to find models for CNC carving.

In this community, you can also follow people from all walks of life. If you're interested in CNC woodcarving, ZenziWerken is definitely one of the must-see accounts. It was created by Daniel, a German who loves woodworking. He has been sharing hundreds of woodworking cases designed and made all by himself over the years for free. Each case is exquisite and practical, with detailed instructions.

Since you can 3D print a 3D printer, be noted that if you simply type "CNC models" in the search bar, the results will mostly be parts for CNC machines. This might often be the case with the following websites as well. Therefore, it is best to search with specific keywords, such as "CNC toy cars". Thingiverse's search filters support only a few categories, which makes the right keywords even more critical.

 

GrabCAD

GrabCAD has more than 9 million users and nearly 5 million model files, all available for free download. The site focuses mainly on models for specialized fields such as automobile, mechanics, architecture, and industrial designs, distinguishing GrabCad from other 3D model repositories. However, you can also find numerous models suitable for CNC carving. For example, the keyword "chess" will return some nice matches.

In addition to filtering by model category, GrabCad's search filters also support specifying file format and the software used to generate the model. To locate the model you need quickly, use precise keywords combined with appropriate filter criteria.

 

MyMiniFactory

MyMiniFactory is one of the most popular 3D model marketplaces with more than 160,000 models. Although not known for its volume, many of the models come from professional designers, and the average quality is excellent. All of the models have been tested by the community to ensure that they can be used for 3D printing, and some of them are also compatible with CNC milling.

MyMiniFactory focuses on paid models from art and pop culture fields such as games, anime and movies. If you're a pro in designing or modeling, this is a great place to cash in on your talent.

MyMiniFactory also provides a small selection of free models. The site highlights easy-to-use search filters, which allow you to refine the results by category, pricing and complexity of the models, as well as the model of the 3D printer used. A direct search for "CNC" returns less than ideal results, and it is best to enter more specific keywords, such as "relief".

 

Cults

Cults is another designer-rich 3D model repository featuring delicate models. The site has over 3 million users and close to 420,000 models. Both paid and free models are available. If you're good at creating 3D models, you can upload your work to Cults and price it in just a few steps.

Surprisingly, searching directly for "CNC" on Cults leads to quite a few models designed for CNC carving. A more precise keyword will undoubtedly return more satisfactory results, though. On an account called "STLFILESFREE", you can find dozens of beautiful models for wood relief carving, all for free.

 

TurboSquid

TurboSquid models are used by game developers, architects, visual effects studios, advertisers, and creative professionals around the world. You've probably seen TurboSquid models hundreds of times and didn't know it. A majority of the one million models uploaded here are priced.

Most of the models on the site are not for 3D printing or CNC processing, but you can filter by STL format and enter specific keywords, such as "relief". You can also filter out free models, although the results may be numbered.

 

Instructables

Unlike the model repositories introduced above, Instructables is a community where DIYers share their creations. Each case contains detailed step-by-step instructions, accompanied by pictures, animations and videos; each step allows other users to add hints or ask questions, allowing sufficient interactions.

From electronics, mechanics, woodworking to cooking, Instructables offers cases of just about anything. On the Workshop subpage, there are separate sections for 3D printing, laser cutting and CNC. The CNC section is definitely a mine of information for experienced CNC players. In addition, the site has a Teachers section, thoughtfully divided by grade level, to encourage teachers to apply DIY cases in their classes. Search directly for "CNC" plus keywords, such as "CNC toys", and you'll likely find some fascinating results. Not every case comes with ready model files, but all cases are available as a packaged PDF file for download.

 

Maker Union

Maker Union supplies free DXF files of high quality with a simple and easy-to-use interface. DXF is a vector image format that is well adapted to CNC machining, which acts as 2D patterns that guide your machine on where to cut. Processing DXF file with CNC machines will not leave black edges as opposed to laser engravers. The finished products are perfect for decoration.

The site features theme-based display of files, where a set of beautiful DXF files can be downloaded as a package in a click. Although the number of themes is just over 240, there are on average 6–8 files under each theme, all of which are ready-to-cut for CNC machines. Maker Union supports keyword search of themes, and you can choose to display the search results by popularity, release date, etc.

 

MakeCNC

MakeCNC offers only paid models of high quality, covering categories such as architecture, vehicles, ships, mazes, animals with a total of more than 1,400 models. Each model consists of a set of vector graphics that can be used directly for CNC machining. Assembly is usually required, and a detailed assembly manual is hence included in the files downloaded. While cutting a single vector graphic poses little challenge, milling complex curved surfaces and carving assembly parts do require more experience in CNC machining.

 

STLFinder

As you can tell by its name, STLFinder is a search engine for 3D models in STL format. Thingiverse, GrabCAD and MyMiniFactory are some of the major 3D model libraries included in its index. The total number of models indexed is huge, with 159,316 results returned for the keyword "wall art" alone. It only supports filtering by paid or free models.

 

Etsy

Etsy is a marketplace focusing on handmade items and craft supplies. Apart from physical goods, there are also paid models under a broad range of categories, including home decor, toys, art, as well as tools; both 3D models and 2D patterns are available. Here you get to see buyers' reviews and photos of finished products on the page of each model file. You can also open your own store on Etsy and price your creations.

Go straight for "CNC file" in the search bar, and you'll find hundreds of 3D models for CNC machining, ranging from woodcut Star Wars calendar to world map relief. The site supports filtering by keyword match, price range, release date, etc. In addition, the search bar provides access to recently viewed items.

 

Craftsmanspace

Craftsmanspace comprises a wealth of free 3D models and 2D patterns. In addition to the two sections dedicated to model files, the Free projects section collects cases uploaded by users along with instructional PDF files. The site also has a Knowledge section full of information, including a comprehensive introduction to woodworking joints completed by illustrations and terminologies.

 

Pinterest

Pinterest is one of the largest image-sharing platforms in the world. Thanks to its volume, searching with CNC-related keywords, such as "CNC cutting design", returns a considerable number of results, including many masterpieces. Browsing through the designs can be a great source of inspiration. Note that only images of finished products are available here rather than source files for CNC machining.

 

 

CNC Tutorial Videos

Whether it's to stimulate your own thinking with others' designs or provide model files that your CNC machine can work with, we hope the above websites have helped you in leaping from ideas to models.  

Now, let's proceed to turn models into solid parts. Here are several tutorial videos on using Snapmaker CNC Modules and software, namely the Snapmaker Luban and Fusion 360.

Tutorial Videos by Snapmaker

Snapmaker 2.0: How to Use the CNC Function

The Snapmaker 2.0 comes with an ER11 collet, an MDF wasteboard, and dust-resistant Linear Modules. The CNC Module is easy to use and supports various types of materials. Check out this step-by-step tutorial on Snapmaker 2.0 CNC function and give it a shot.

How to Use CNC Function with Rotary Module

Follow along this video to see an entire 4th-axis CNC machining process with the Rotary Module. We've added new features of Origin Assistant and Bit Assistant to the Touchscreen and realized full support in Snapmaker Luban. 

Intro to Snapmaker Luban 4.0 for 3-axis CNC Carving & Intro to Snapmaker Luban 4.0 for 4-axis CNC Carving

Learn how to use the 3-axis and 4-axis CNC with Snapmaker Luban 4.0 with a brand new interface, improved workflow, and some useful newly added features.

Fusion 360 CAD & CAM Tutorial for CNC Beginners [Snapmaker Academy]

Follow this video to design a 3D model in Fusion 360 and carve it out with your Snapmaker. The whole process could be much easier than you would have expected.

Tutorial Videos by Users

Snapmaker Tool Changes: Fusion 360 3D Relief Milling

Rodney Shank made this video for anyone who wants to know how to mill a relief on wood using Fusion 360 and the Snapmaker 2.0. In this video, you will be guided through the whole process step by step, including changing tools from rough to finish carving.

4 Axis CNC Machining with Snapmaker 2.0
In this video, Nikodem Bartnik tests and reviews the Rotary Module of Snapmaker 2.0. He succeeded in milling some cool stuff like SpaceX model out of epoxy tooling material and wood while failed with aluminum.

Snapmaker 2.0 - E04 - Using the CNC

In this project of Koka-Bora Creations, the author demonstrates the process of carving an SVG image onto a piece of wood relief using Snapmaker 2.0. In addition to the practical steps, he also explains how CNC relief works, the pros of working with SVG greyscale images, and some other principles.

 

Armed with the above resources, you're well-prepared to try it out now. Just get your Snapmaker CNC Module going and bring your creative sparks to life!

In the future, Snapmaker Academy will continue to provide you with helpful CNC resources and knowledge, so STAY TUNED!

If you are interested in other topics of 3D printing, feel free to contact us at support@snapmaker.com, or leave your message in our community.

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