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?.
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:
- Import the model to CAM software;
- Set the coordinate system and define the position and work origin of the stock (i.e., the material to be carved);
- Specify stock parameters, such as its dimension and orientation;
- 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;
- Preview the toolpath in simulation to visualize in advance how the tool moves and what the finished product looks like;
- 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!
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.
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.
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!
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.