Design & Manufacture
Now that you are reading this guide about 3D Printing, we bet you know the word “STL”.
STL is short for Stereolithography. It’s a file format created by 3D Systems company who’s known as one of the pioneers in 3D Printing industry. Born in 1987, this “30+ years old” format is still widely used for Prototyping, 3D Printing and CAM. For 3D Printing, STL might be the most commonly used model format.
So, what is STL? To put it simply, STL contains a limited number of triangular facets which describe the surface geometry of a 3D object. Think about a football that is made up with several pentagons or hexagons, an STL file works the same way. One thing that makes STL model different from other common CAD model is that it has no attributes of color, texture, etc.
As long as you have an STL file downloaded online or shared by others, you can import it into a slicer software and then print it out, making it quite easy to use. But obviously, things would be far more interesting if we can edit an STL file creatively. So, can we? The good news is yes, we can. The better news is we can do it at no cost – with the help of the free Autodesk Meshmixer software.
In the debut of Snapmaker Academy, we’d like to show you how to customize a Snapmaker Original Egg Capsule Toy, and share some ideas and tricks about editing an STL file.
Tools & Materials
What You Will Learn
You are going to learn how to use Meshmixer to:
- Transform the size, orientation, position and shape of an object;
- Get a new object by calculating the Boolean difference between 2 or more objects;
- Add text on an object;
- Stamp the objects and make sunken patterns by extruding;
- Separate parts of a model and export them as independent ones.
5 steps are included in the guide:
- Make a cuboid that hollows the egg;
- Hollow the egg;
- Decorate the surface of the egg;
- Separate the machine parts;
- Export models and print.
Step 1: Make a Cuboid
- Import the egg.stl file.
- Select Import, and Append the machine.stl file.
- Hide the egg in the Objects Browser for the convenience of later operation.
- Select Meshmix -> Primitives on the sidebar, and drag the cuboid to the workspace. Rename the cuboid by double-clicking it in the Objects Browser, if necessary (e.g. cube).
- Use the mouse and the ViewCube (on the top right corner) to change the camera, and roughly adjust the size and position of the cube to make it coincide with the machine.
- Select the machine in the Objects Browser, and choose Actions -> Set as Target in the menu to turn it translucent.
- Adjust the cube precisely until it encases the machine perfectly. Select Accept when finished.
Step 2: Hollow the Egg
- Choose Actions -> Clear Target to restore the view of the machine.
- Hide the machine in the Objects Browser.
- Select the egg and turn it translucent through Actions -> Set as Target.
- Select the cube and choose Edit -> Transform on the sidebar. Rotate and move the cube to the center of the egg.
- Accept when the cube is in position. Choose Actions -> Clear Target and click on the eye icon to restore the view of the egg.
- Select the egg in the Objects Browser, hold “Ctrl” key, and check the cube. A menu will pop up at the top left corner.
- Select Boolean Difference in the popup menu.
- Uncheck Preserve Group Borders and Auto-reduce Results to avoid an automatic smoothing for the model which may lead to damage or deformation. Choose accept when finished.
- Turn the egg translucent in the Objects Browser, and check if the egg is properly hollowed.
Step 3: Adding Text
- Restore the view. Select Meshmix -> Letters, and drag a letter onto the egg.
- Use the mouse to adjust the letter. The center of the control button represents position, while the ring is for orientation, and the arrow is for size. When finished, choose Accept.
- Add all the letters needed.
Step 4: Adding Sunken Patterns
- Select Stamp on the sidebar. Left-click the target pattern, and left-click on the egg where you want to draw the pattern, then drag to adjust the size of the pattern.
- Choose Select on the sidebar, double click the pattern(s) that you want to extrude.
- Choose Edit -> Extrude under Select. Set the offset to make sunken patterns on the surface. Choose Accept when finished.
Step 5: Separate and Lay the Machine Parts
- Hide the egg in the Objects Browser, and show the machine.
- Click on the machine, and choose Select -> Edit -> Separate on the sidebar.
- Select the machine in the Objects Browser again and continue separating the remaining parts.
- When separation completes, select all the machine parts and choose Analysis -> Layout/Packing on the sidebar for a horizontal alignment.
- Show the egg and move all the machine parts to a proper place through Edit -> Transform. Accept when finished.
Step 6: Export the Models and Print
- Choose and Export the models one at a time.
The exported STL file can be sliced and printed with Snapmaker Luban software. For detailed instructions, you can refer to Chapter 3.3.1 to Chapter 3.3.3 of the Snapmaker 2.0 machine Quick Start Guide.
Before Starting, you need to rotate and position the models properly to avoid overhangs. See below:
It’s suggested to use Normal Quality mode in Snapmaker Luban to print.
The printing results using Snapmaker Original are as follows.
Remix & Share
Meshmixer is not the only option for editing STL files. Some tools that you might be more familiar with, let's say, Fusion 360, Recap and Zbrush are worth trying, too. You are welcome to share more useful applications with use if you’ve got some.
Well, what if I don’t want to put a machine into an egg? When you know how to use tools like Meshmixer, it’s up to you.
We are going to create a topic in Snapmaker Forum for each term of Snapmaker Academy. Why not come and meet other passionate makers to share some brilliant thoughts and designs?
Oh, and wish you happy making!