Saw this online and am wanting to make something similar to keep some of my tools getting lost in the bottom of tool boxes. Mostly hand tools as pictured. This looks like both the cleats and took storage is made from 18mm birch ply, thoughts on making this from either some 18mm or 12mm hardwood ply instead? Trying to save my wallet. I was thinking that maybe some 12mm hardwood ply might be suitable for hand tools and i have a local supplier who is pretty cheap for hardwood ply.