Question about a stuck shutter on a Yashica-Mat EM

I was fixing up a Yashica-Mat EM last week and the shutter blades got stuck halfway open after I cleaned them with lighter fluid (the usual trick). Turns out I didn't let the fluid fully dry before testing - left it for 20 minutes instead of an hour. Has anyone else had this issue with leaf shutters and what's your drying time rule?

3 comments

3 Comments

the_olivia1mo ago

I used to be in the "lighter fluid dries in ten minutes" camp myself, honestly. Then I gummed up a Copal shutter on an old folder so bad it took me three days to unstick it with isopropyl and a toothpick. Now I wait at least an hour, but really I'll leave it overnight if I can. That extra time lets the solvent evaporate out of the tiny gaps between the blades, not just off the surface. Twenty minutes is basically a guarantee you'll be redoing the job.

cooper.drew1mo ago

Sat here staring at my screen for a solid thirty seconds after reading "three days with a toothpick." That's the kind of patience I just don't have, man. I've definitely been lucky so far but your story makes me think I need to start waiting overnight too.

moore.beth1mo ago

The lighter fluid trick works great but you really have to give it time to fully evaporate out from between the blades. I learned that one the hard way too and now I always leave it overnight minimum, just to be safe. Twenty minutes is asking for trouble with those tight leaf shutter gaps.