Please use this updated version instead: http://www.thingiverse.com/thing:200895
I'm moving FAST on this design. I've made a number of improvements and you're probably better off waiting a few days while I finish up working on the design. Check out my blog for more on this and other drawing robots (including more instructions, etc) http://plotterbot.com and the Robot Hacks (https://plus.google.com/communities/114867980170611537174) page for the latest pics and development.
Recent change NOT included in these files:
Added an actually useful Y stage rack
Added a crappy pen holder (soon to be less crappy)
Many parts now interlock for a better fit
To learn more about this project, check out this blog post: http://plotterbot.com/2013/11/an-itty-bitty-drawing-robot/
This is a VERY (very, very, very) beta version of a tiny CNC robot. I wouldn't suggest playing along at home unless you're really interested in getting your hands dirty. I've included a MakerWare file with all the parts on a single plate to fit a Replicator 1. This is the very first version I've tried to print and I can already see lots of room for improvement. However, it is extremely cheap to build (estimated $50 - which includes the cost of a $30 Arduino Uno) http://plotterbot.com/2013/11/tiny-cnc-drawing-robot-cost-estimate/
Right now all it does is run the basic Arduino servo "sweep" sketch which isn't that impressive. However, I'm planning to add a better Y stage so it can hold a pen and, hopefully, start drawing small pictures.
I'm using a slight variation on Sasa's rack and pinion OpenSCAD code. I've made some minor changes to their code and included the variation here.
This project was inspired by the Make Robot Hacks project (https://plus.google.com/communities/114867980170611537174) and the Piccolo tiny CNC robot by Diatom studio (http://www.piccolo.cc/).
A video of the robot in action: http://www.youtube.com/watch?v=GPAihIzBYKE
Right now there are only six parts. I'm trying to design this 'bot to be fairly easy to hand assemble quickly. Briefly, you would build it as follows:
1) Place the large base (Xrack014.stl) on a flat surface
2) Insert a servo motor into the X stage motor mount (Xmotormount014.stl)
3) Put the X pinion onto the X stage servo (Xgear014.stl)
4) Put the X stage motor mount with pinion into the base
5) Put a servo motor into the Y stage motor mount (Ymotormount014.stl)
6) Put the Y pinion onto the Y stage servo (Ygear014.stl)
7) Put the Y stage motor mount with pinion onto the X stage
8) Place the Y axis rack between the Y pinion and the X stage motor mount