I have never used it either. Do use lock nuts on 4-40 clevises though. I won't touch a plastic clevis on anything with a motor. Save them for gliders. I have had one strip and lost a plane because of it, but only one. Never seen a problem with metal, other than one dough head that put the wrong size clevis on the wrong rod and it came off. that was a given that it wouldn't work though. The rest of his plane had problems too but he was one of the newbie "I don't need your help" type guys.