pic: Sheet Metal with VexPro parts

[Madison]

Here's an okay look at what I roughed in for chain tensioning on the end wheel sets.



The white parts on the right side are part of the tensioning system. One is a U-shaped bracket that straddles the wheel and captures the axle in two places. The axle continues through that part and into the blue frame pieces where it can slide in a slot. The black pieces are acetal disks that act as spacers and as thrust washers and should help to spread side-loading out over a larger area than a typical washer or the bolt head.

The bracket also has a captive nut installed. Threading a bolt into that nut will pull on the wheel and tension the chain. The second, right-most white part is the fixed plate the bolt pulls against; it could just as easily use the blue, outer drive train cross member, but I wanted to avoid having the bolt head stick out into where the bumpers will sit and it also makes it possible to assemble each side of the drivetrain as a 'pod' without putting together the entire frame first.