I ended up redoing the whole shutter curtains. The material itself was fine, so I salvaged that, but the stitching and adhesive were in bad shape. Anyway, I've got it reinstalled except for final cementing of the first curtain ribbons. They're taped with double sided tape, but I'm waiting to cement them until I can verify that everything is working correctly and in the correct positions.
However, I'm running into some trouble that I don't quite understand. The symptoms are as follows:
- When I wind/cock the shutter, then press the shutter release, the shutter doesn't quite fire. I have to give it a little nudge by turning the shutter speed dial just a bit clockwise. It's as if something is catching that shouldn't be. When I look at the mechanism at the bottom of the film sprocket shaft, I see the bottom plate press down and the pin on the bottom plate clear the pin on the top, but it rotates a very short amount (a couple degrees) before catching and stopping its rotation. I have to gently nudge it then it finishes its (fast) travel around and the shutter fires. I also notice that I can gently nudge the second curtain latch pawl toward the back of the camera and the shutter will fire.
- More problematic, though possibly caused by the same underlying problem, is that when the shutter does fire (with my helping it), both curtains always fire at the same time, so there's no opening. In other words, there's never a delay between when the first curtain releases and the second curtain releases. The service guide for the camera that I found mentions that this is most commonly because the spring on the second curtain latch pawl behind the shutter speed dial has slipped off, but I've confirmed that's not the case. (Though it's entirely possible that its positioning, tensioning, or something else with that pawl is wrong, I suppose.)
I'm trying to figure out what to look at next and would appreciate any advice. To be clear, my goal with doing this repair myself is less about fixing the camera (though I do of course want to fix it), and more about learning and enjoying the process. I've actually really enjoyed my time working on it so far. I have plenty of working cameras to shoot with, including a couple Barnack Leicas.
To allay any concerns and hold off any suggestions that I send it to someone for repair: I have not yet(?) done anything that should cause irreparable damage -- no lost parts, broken parts, stripped screws, etc. I have a well stocked workbench and so far have had all the proper hand tools, etc. I think my main issue is just that I don't have a full understanding of how the mechanism is supposed to work and thus how it can fail.