hub assembly
Keith Rowell Design

The discussion of tire size and torque has been lively, and Dale has kindly volunteered to evaluate the torque vs. tire size for our particular configuration. "Eyeball" estimates seem to bear out the 10" tire size for this gearbox. So I've included some plans for connecting the 10" tires that Mike has.

Some evidence that 10" might work are; that the kiddie cars these gearboxes come from use 10"-13" tires; it's almost impossible to stall by hand; and the ground clearance of the gearbox using 6" tires is minimal. 8" might be ideal if we had any.

The 10" tires Mike has offered are pneumatic with a plastic hub, very nice. Theyre wider than the 2" "dummy" tire I had in the model last week. Mike has a plan to modify the hub so that those two inches are again removed from the width, maintaining our 22" approximate width. This modification ivolves casting a plastic "interlocking" hub that molds to the cavities of the gearbox hub and the tire hub, "lovejoy" style. We don't have lug nuts or wheel locks for this larger shaft, our plan to date is to weld washers on the in-board side, and use cotter pins and washers on the outboard side.