About the only times I buy material at a big box home center are when I need something in a hurry for the house, or I’m working on an “I Can Do That” project for the magazine. For the June 2011 issue I built some simple bookcases and used 1/4″ thick plywood for the backs. I didn’t pay much attention to the actual thickness, I set the rabbet cutter on my router a little deeper than the thickness of the plywood without measuring. This week I’ve been making drawers for a project that’s been on the back burner for a while and when it came time to put in the bottoms I decided to use the leftover plywood. I thought it would be a good idea to measure the thickness of the plywood so I could size the grooves accordingly. What I found surprised me. It was like seeing a flock of passenger pigeons flying by, or a British car that doesn’t leak oil.