Construction of practice parts for the kinetic sculpture race begins! As practice I am beginning with the sandwheels, which are 8″ wide, 36″ diameter, truck inner tubes held in foam/glass sandwich wheels. I’ve opted to treat the wheels as practice also for the foam fiberglass sandwich construction which I now think will comprise the hull / vehicle frame. The wheels should at least be plausible for both the kinetic sculpture race and race to alaska (even if in the end I decide not to burden the longer race with any excess landing gear.)
The hubs are an interesting design opportunity to experiment also with casting fiberglass. I think I can make the hubs, with a nice conforming keyway spline in the 1″ bore, by laser cutting a simple acrylic mold around the actual shaft and spline to be used, which would be extremely well waxed with mold-release. Being a 1″ shaft, I can also thread the end of it and make a nut capable of producing a thousand or two pounds of axial force to drive the hub off the shaft, flexing the glass, if needed – it should have some elasticity.