Vent: That week I tried to fix a jammed shutter on a vintage Pentax

Spent five days straight trying to unstick a shutter on a Spotmatic I got for $30 at a thrift store. Ended up snapping the curtain spring on day three and had to order a replacement from a guy in Germany. Has anyone else had luck with those old Copal shutters or should I just toss it?

2 comments

2 Comments

julia2863d ago

I used a tiny drop of lighter fluid on the Copal shutter in my old Mamiya and it freed it right up after a day of soaking. Had to work the release slowly with a toothpick to get the gears moving again, but that spring snapping issue usually means the tension was way off from the start. You might save that Spotmatic yet, just check the timing with a phone app before you trust it with film.

taylor.jessica3d ago

80% of the time lighter fluid eats through old lubricants and then dries out the surfaces completely, causing more sticking later. I have seen that trick work on some cameras but it usually makes the timing drift way worse after a week or two. The real issue with those Copal shutters is that the old grease turns into glue, and lighter fluid just moves that gunk around instead of actually cleaning it out. You should pull the shutter apart fully and use proper naphtha or isopropyl if you want it clean. That Spotmatic will give you inconsistent exposures if the timing is off by more than a few milliseconds, which is super common after a lighter fluid bath. A phone app can catch the big errors but it won't fix the underlying problem.