Seems to me they’d tear out after a little while.

We used 10-24 all-thread rods anchored with JB Weld, as I didn’t have any 2-1/2 inch 10-32 screws. She tapped a test coupon, clamped it in the vise, and gave the (un-glued) all-thread a mighty yanking, all to no avail. I don’t like it, but it will survive longer than anything else I can think of and it’s as good as it’ll get.

The outer end of the all-thread gets nylon locking nuts over spring washers to keep the case stack in compression.

that would require recesses in the longboard

Which was, shall we say, vetoed early in the design process… [wince]

A thicker plate moves the truck too far from the longboard; there are complex issues of balance and responsiveness and riding technique that I do not profess to understand.

a high-vibration, high-impact environment

I’m not entirely pleased with the overall design, but the battery’s as well-armored as I can make it within the other constraints.

The big fear: a wire shaking loose from a cell or the battery protection board, shorting a cell outside the polyfuse and protection circuitry, ending with a catastrophic lithium cell failure inside an ABS plastic case. We’ll put a dab of flexy acrylic adhesive on those joints, pack that part of the case with foam to immobilize the wires, cross our fingers and eyes, and hope for the best.

It is a way complex project and she’s learned a lot more than she expected… [grin]

You’re anchoring screws in a high-vibration, high-impact environment with the scant few threads’ engagement you’ll get in an aluminum plate? Seems to me they’d tear out after a little while. However, I can’t think of a good way to put ordinary hex nuts
on the ends, as that would require recesses in the longboard to accommodate them. Hmmm.