Geez Chris... I thought you knew that. You can't just clamp directly on to your backing strip... it's too thin. What you ended up with is what happened... gaps and waves. You can use clamps like you did, but you need to put a strip of wood over top of your backing strip, so it's sandwiched between them. That way, it evens out the pressure. You could ditch those expensive clamps and get some inner tubes. Also, don't waste that osage. Sand off that backing strip and start over!