Tripod mount ring for Canon 100mm macro

Origin:
======

Canon lens are great but Canon Inc. can be stingy about accessories and deliver it's 100mm marco lens without a tripod mounting ring. Worst they sell it apart more than €200! So this is my solution.

Strange shape:
=======

You'll find the shape strange... me too, but I can explain!

For the hinge, I need 20mm wide. But a 20mm ring does not permit the fixation onto my camera (and I suppose many over). So I just made it 20mm on hinge side 10mm on the over! Done... But th