Buckie B, I will have a look at the lugs again tommorow, I'm not one for actually taking drums apart, it looked ok from the outside when I last looked. I don't know about internally though. Makes sense what you say about calf/ plastic too.

Hope not, but reads like the tension rod insert has taken a chunk out of the lug casing retaining bits. The insert is steel and quite a bit harder than the pot metal casing. May not have cracked the lug. If so you can replace the missing with JB Weld and file excess until insert fits tight. Hope the attached is of some help.

Creighton

Or perhaps the threads are stripping on the insert. You can sometimes feel a bit of a "jump" when the thread lets go. No cracking noise just muffled curses from myself.

I think it just means- 'drum says- please don't tension me to hard'. I've backed it off just very slightly but all seems well - without taking it apart and checking that is, - no visible damage on the outside at least. When I think about it it probably did turn on the inside - that bolt bit.