I picked up this one because it was cheap. It was described as having a non-working shutter … my guess, mechanical failure. Since I used to have the Canon F-1n (New version), I thought I would give it a shot.
Well it turns out that it was more than just a mechanical problem. I get the camera and the shutter button cannot depress, and the winding arm is in a locked position.
I open the back and do not see any shutter curtains … but wait, I see a small crinkle of thin metal poking out the left side … I take my tweezers and pull out the ripped titanium second curtain.
It appears that someone was clumsy enough to rip the shutter.
I am envisioning … opening the back to put some new film in.
Pulling the film leader across … camera slips and thumb goes right through.
Ok, now to figure out why the shutter release/winding is stuck.
For this I need access to the bottom gears.
Unlike my F-1n, the only thing holding the bottom plate is the battery door.
There are three plates to remove … though only the left one is actually needed in this case.
I tried turning the winder coupling to see if any of the mechanisms moved … and they did.
This is good news.
There is one part in the middle that has a notch in it. This notch allows the shutter button to be depressed. If the shutter is partially wound this notch will not line up with the shutter release arm.
After turning the winder coupling completely, knotch mated up to the shutter release arm and I was able to depress the shutter.
I noticed during the winding that a spring had come loose. This spring pulls two toothed arms together so that the shutter release cam can be turned. Since the spring fell off one side, the cam could not be turned into the correct position.