wood

[BrianG]

Depends I guess. For the tray to be fairly strong when made of wood, I would think the walls would have to be about 1/8" thick (like plywood) to handle the inertia of the batteries when the vehicle hits something, lands from jumps, etc. If you make the walls too thin, the cells will break right through. I dunno - maybe. For the work involved, I would rather use something like fiberglass so you can make some pretty crazy shapes.