My current plan is 10.5" wide, 20" long and 12" high. I am adding an additional 20" board at the top (3 wide) so the tire has a full surface to rest on, and I am making it a 2 part assembly like @75slant6 did. Current projections show that I can get everything out of (14) 2x4x96 @ $4.52 each, locally. So like $70 for the wood. Not as good as it used to be, but better than the plastic ones at $200 a pair or more.