Some Kyocera-Contax SLRs such as the RTS/RTS II and the AX are said to have it, and two of my Yashica TL Electros definitely do have it, the nasty habit of having their mirrors creep down the mountings until they protrude as far as to collide with the rear elements of the lenses--or some lenses, at least--and get stuck.
(Now I do know that some M42 lenses are simply incompatible with some M42 camera models, yet this is not my point here. I'm quite sure this is a mirror issue.)
With M42 cameras worth 30 bucks or so each, a professional repair service is out of the question, of course. On the other hand, I'm not prepared to always keep in mind which of my lenses I may use with which of my cameras without chipping or breaking their mirrors.
That's why I'm thinking of tinkering around a little with those cameras myself. My idea is to use a hair-dryer to apply some moderate heat to the mirrors, hoping to soften the glue underneath so that I can gently push them back where they belong. So much for the theory anyway...
Bright idea? Soft idea? Is there anybody around who tried something like that before?
Any helpful hints would be gladly appreciated.