Aside from this wheel looking awesome, this design doesn't require an edge groove nor several layers to create a channel to hold the rubberband in place.
It solved my need for a small radius wheel - I had no small rubberbands or O-rings on hand.
Step 1: Lasercut the Design
I engraved the space for the servo arm deep enough so that it was flush. You can adjust it for different arms or axels.
Weave the rubberband between the grooves. For this 40 mm diameter wheel, I used 90 mm x 3 mm rubberbands. The depth of the groove left about .5 mm of the rubberband above the surface so that there is traction. You can probably use wider rubberbands, but definitely not thinner.
Towards the end, it gets a bit tricky to slot so ask someone to help if you can.
Step 2: Ta-daa
It works really well and looks supercool.
Step 3: A Similar Wheel I Made a While Back
I made a similar wheel a while back. I used some rubber dots folded in half and wedged into the teeth. The rubber dots were post-industrial waste from some gasket manufacturer. I imagine if you wanted to replicate it, you could cut some rubber thick rubber squares instead, but at that point, there are other options.
Still, thought it was an neat looking wheel as well and it worked really well.