I built a shed recently with a wide door to accomodate big tools.  I made this door out of 2x6 tongue-and-groove decking boards, which I needed to clamp together to attach 2x4 bracing.  So a pair of "Pony" clamp fixtures and a couple lengths of black pipe was just the ticket -- or almost.  The decking boards needed a bit of persuasion to get all 9 planks together, and I didn't want to gouge the nice oak.  Some cedar shims against the clamp pads promptly crumpled when I tightened the clamps.  So I left the door until the next weekend and ordered these clamp pads.