Kinetic Sculpture Race Build Update: Molded Composite Hubs and Foam Composite Wheels

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.