Simple industrial design of a robot wheel. Ideal for small robots. I designed it for my balancing robot when I realized factory made wheels are too expensive.

Outer diameter: ⌀65mm Shaft: ⌀4mm (⌀5mm should be also good). Wall thickness: 3mm

You can stick encoder pattern on the back if you like.

1. Drill hole ⌀4mm or ⌀5mm optionally. (STL hole is ⌀4mm but printer tends to make a bit smaller holes).
2. Put small M3 nut into square hole.
3. Screw M3 10 into nut.
4. Put piece of gum as a tire. In the reference project 20mm wide bicycle inner tube was used.

Assembling guide: http://youtu.be/joJXfW-BkHc