pic: GUS Team 228's Prototype Sheet Metal 6WD Chassis

[artdutra04]

Originally Posted by Chris is me

Probably a silly question, but what's changed since the last design and why did you make the changes?

We went from single-speed to dog-shifting transmissions, from 5"x2" to 4"x1.5" Colson wheels, from 35p to 25p roller chain, from keyed shafts to hex shafts, changed hole pattern from #10 clearance on 3/4" spacing to alternating #10 clearance and 5/32" (for rivets) on 1/2" spacing, and overall dropped a lot of weight.

Also, the standoffs were modified to have a Delrin sleeve over them. As shown, it was designed for an exact number of even number of 25p roller chain links, so as to eliminate need for a master link. In this state the chain does not contact the standoffs, but as the chain stretches these standoffs can be moved to act as tensioner. Another benefit these standoffs have is it allows us to nest pneumatic accumulators into this (otherwise wasted) space to help keep COG as low as possible:



However, depending on whatever curve ball the game throws us, we may opt out of using these standoffs in lieu of a single sheet metal belly pan and/or sheet metal superstructure parts. If we had access to a live-tooling lathe, I'd combine the sprocket and knurled insert hub for the outer wheels into a single piece, to allow the end shafts to be dead axles.