Thursday 13 June 2019


When I used OpenSCAD to design Mendel90 I modelled complete assembly views with all the vitamins in place and a significant part of the code was actually the vitamins. Vitamins being the RepRap term for non-printed parts of a 3D printer, fasteners, motors, etc. I also automated the generation of the bill of materials, STL files, DXF files and PNG assembly views, but making the build manual was still a lot of manual work, pardon the pun.

After Mendel90 production ended I started designing other projects and found myself needing to use its vitamin library, but because it wasn't designed to be stand alone, that quickly got messy. Eventually I made a new stand alone library and a more general Python framework that would work for any project.

Over the last few years I have refactored it many times, making it much faster to preview, more general and more automated. In particular it can now catalogue all the vitamins and automatically make build manuals for any project using Markdown embedded in OpenSCAD comments. There is a simple example here. I also added reusable printed parts, such as feet, hinges and handles and some reusable enclosures.

It will never be complete because each significant project I make with it usually needs a few more types of vitamin, but it is hopefully structured so that it can grow sustainably without bringing OpenSCAD to its knees. To do that I had to fix some issues in OpenSCAD itself because it used to slow down exponentially with the number of files used. The picture above has an instance of every part in the library. The latest release of OpenSCAD can draw it in about one minute on my desktop PC. This is remarkable because at one time it took 12 minutes.

Here is an example of a typical assembly views it creates: -

I have published it open source on GitHub to enable me to publish projects that use it in the future. I use it for every project I make now, so I don't have any stand alone scad files that can be put on Thingiverse, for example. Feel free to use it in your own projects.