This is a mechanical toy set completely deigned in OpenSCAD with the help from MCAD libs and aubencs screw library, https://www.thingiverse.com/thing:8796

I've uploaded a calibration file, if it works well, download the rest of the files from github at https://github.com/ErikHK/mek
otherwise follow the instructions in calibration.scad.

There are a number of different parts in the file mek.scad which you can compile and print out, or configure the scad files yourself, or even completely design yor own modules!

This is still very much a work in progress, but here are some cool (imho) demonstration videos:

https://www.youtube.com/watch?v=t6cLQfb-TtE
https://www.youtube.com/watch?v=z7tqoTtM524
https://www.youtube.com/watch?v=jXWeNPY7V3E