I’ve often wondered why there’s only one ring. Now you’ve explained why it makes perfect sense thanks. I’m always amazed how much people on the forum knowbecause when you tighten the locking ring up it grips on the stone and the disk slightly turns on the metal ring it centralises the disk as well if it wasn't there tightening and undoing the disk would grind the arbour and lock ring away
its a depressed disk so behind
Don't assume anything.Haha, good point
I assume the same for the flat ones