Wheels for Cubelets modular robot

UPDATE: Check out the new improved version here: http://www.thingiverse.com/thing:1421337 - it includes an option for free spinning wheels that attach to any Cubelet.

These are magnetically attachable wheels for the [Cubelets](http://www.modrobotics.com/cubelets/) system from [Modular Robotics](http://www.modrobotics.com), a construction system for quickly building robots. They are designed to attach to the "Rotate" Cubelet to give robots greater mobility. You will need to reprogram the Cubelets in opposing sides to turn counter-clockwise.

It requires washers, and o-rings to use as the tires. The washers I used have an outer diameter of 1" and an inner diameter of 1/2". The dimensions are in the OpenSCAD file, so you can change them. You can probably get by with an OD 1mm smaller and/or an ID up 5mm larger. A larger ID will give a stronger piece, since it will allow the "pie slices" to overlap the hub more. Check McMaster Carr and see what they have...

The o-rings I used for t