Rack and pinion to move lego parts

This model is part of a lego based 3D chocolate printer.

and is part of
https://sites.google.com/site/kidscodemakespace/

Get the openscad "source" code from github
https://github.com/keesj/3d-makelib/tree/master/legocnc

The motor used was
http://www.vanallesenmeer.nl/5v-stappenmotor-met-ULN2003-driver-

Video of the device in action:
https://youtu.be/cAP1mtJGGqM