The swivel tightening ring broke, I guess I adjusted it too tight. Any 3rd party replacements? It seems that the ball is 20mm or 0.78", and the tightening ring is 30mm in diameter. Found 17mm and 22mm rings online but no luck for this one so far.
I never could get mine tight enough so I replaced it with a hinge. Removed the hinge pin and replaced it with a machine screw so I could adjust the tightness.
Works great but I haven't tested it to see if the metal interferes with the controller signal.
Attached the upper part of the hinge to the holder using 3M VHB tape- holds like iron.
The lower part is held in place with 2 small machine screws. I cut 2 shims out of some scrap aluminum to help hold it in place
My ring started cracking so I covered the crack with 2-part epoxy and laid 2 small metal pieces (leads from an old resistor) in the epoxy. Never tried it but it's an option if you don't want to do my "hinge" mod.