I helped with the design details with shapeways builder CAA52 to make the Mack spoke wheels. I gave the specs of the stock tamiya tire and such and made sure that the first prototype wheels worked and looked the part. im not sure what the stock tamiya tire scales out to be a 22.5 or 24.5? I think the tamiya budd and the shapeway spoke wheel was closer to a scale 22.5. but I cant recall the exact specifics of it.
