I purchased a Nagaoka wooden field camera and it came with a Nikkor lens and Copal 0 shutter assembly. The shutter made a rattle sound and did not close all the away. The lens had a very slight fungus in it, nothing that would impact image quality. I figured with all of that it was a write off so I decided to take it apart and see if I could fix it.
So I started to disassemble it, here is the shutter that will not close. Turns out after taking it apart one of the speed escapement screws had come out and wedged itself in the shutter blade grooves.
Here are the shutter blades, they just fell out when I turned it over
Shutter blades removed
Here it is pretty much taken apart
Here is the speed escapement, another problem I found after a couple of weeks of head scratching was the small spring wrapped around the small brass post had come undone. That basically caused the shutter to operate at one of the middle speeds all the time. After I figured out how the escapement mechanism worked I deduced it had a spring problem and removed the whole assembly and saw the loose spring.
Here is a close up of the speed escapement assembly
This shows the assembly with the speed escapement removed
This shows the assembly with the speed escapement and shutter blades installed
Time to put it all back together again, here is the speed cam installed. Best to line up the 1/15 first, turn to T and then with a small screwdriver pull out the blade stop lever pin to line it up in the speed cam
Final ring assemblies installed
Completed lens assembly done and ready to use, speeds all sound good but I have no way to test
Was finally able to get out and use the repaired shutter. The Goat Canyon Trestle in Anza Borrego Desert State Park.
Arista EDU ISO 100, Nikkor 135mm, f/64, 1/4, Y48 Filter
Seems to work great