Coaster Maker in FreeCAD

Looking for something useful to print with your MMU?

In preparation for a family reunion my wife was planning I created a macro that generates a memorial glow-in-the-dark coaster.

I posted the FreeCAD 0.17 version I for the public on GitLab and forgot about it until the reunion.

Glow-in-the-dark design

I experimented with different structures and settings for the Multiple Materials. Here is what I determined:

  • A white reflector underneath the glow material is more effective than solid glow material.
  • Glow material with fill work as well if not better than solid layers.
  • Dark lettering looks best and is easy to read in the dark.

Upgrade to FreeCAD 0.18

The coasters I made were a big hit at the reunion so I decided to demonstrate the printer and create a few more. Unfortunately I had upgraded from FreeCAD 0.17 to 0.18 and the macro didn’t work but I updated it and thought I should blog about it.

I did this code while learning FreeCAD and isn’t well documented but it works well enough for my needs so I updated it enough to keep it current.


FreeCAD macros are written in Python and the FreeCAD environment has given me a solid foundation to grow my CAD skills. Multiple Material design adds more complexity but I’ve found working with FreeCAD macros it is manageable.

FreeCAD is evolving and you can expect what you write for the current version. You can run multiple versions of FreeCAD so it isn’t hard to run older scripts if you have need. The changes are related to using updated libraries and newer versions of Python so there is usually plenty of information available.

If you have an MMU and would like to customize your own coasters download and run it as a Macro. Close -> Discard and rerun to change values. Enjoy!

Author: Marc