[Brandon Holley]

This year we cast the urethane "tread" for our shooter wheel. We had a ton of issues finding a material we really liked for our 2006 and 2009 shooter wheels. In 2009 we ended up using BaneBots wheels, and because we liked the grip they provided, we wanted to duplicate their material, but with our own wheel setup.

We went for a wheel with high rotational inertia, so we built a central hub/drum using a thick-walled aluminum tube. We 3D printed a mold, that held the drive shaft of the hub, and left a gap for the urethane to fill in and provide the shape we wanted. We ended up going with a concaved wheel to help ensure the ball was centered as it came through our shooter. Due to this shape, we had to build the mold in 3 pieces so we could get it apart.

One cool aspect of 3D printing the mold was we could add patterns to the urethane by adding them to the 3D printed mold. We decided to add some flare to ours with our team number:


The material worked out great. It had a great amount of grip to the ball, and was extremely robust. We never needed to change or even clean the tread material after an entire seasons worth of matches. I imagine if we ever build a shooter wheel again, or even some kind of intake roller, we may go back to this solution.

-Brando