Just got a rolleiflex k2a that was stored 40 years with a stuck shutter. I removed the lens elements and took it down to the speed control ring and flushed it out with lighter fluid. The good news is it now fires and sounds good, bad news is at about 1/25 and slower, the shutter sticks open till I rotate speed ring to a faster speed. I didn't take any of the clockwork apart, pretty sure I got all the spring loaded parts in place when I replaced the speed ring (3 parts as far as I know) and put VERY small drops of sewing machine oil on the shafts of the slow speed gears. Any ideas where I went wrong or maybe pics of how it should look?
Just got a rolleiflex k2a that was stored 40 years with a stuck shutter. I removed the lens elements and took it down to the speed control ring and flushed it out with lighter fluid. The good news is it now fires and sounds good, bad news is at about 1/25 and slower, the shutter sticks open till I rotate speed ring to a faster speed. I didn't take any of the clockwork apart, pretty sure I got all the spring loaded parts in place when I replaced the speed ring (3 parts as far as I know) and put VERY small drops of sewing machine oil on the shafts of the slow speed gears. Any ideas where I went wrong or maybe pics of how it should look?
Synchro Copurs are overly complicated and delicate. Flushing will spread dirt and lube to new paces. It needs to be stripped down,cleaned, relubed, and reassembled, as has been said.
The only Synchro Compur I have brought back to life was on a Rolleicord Va. I added three very small drops of oil, one to each main pivot in the slow speed mechanism. If it hadn't worked, I would have been looking at a complete strip down in my experience.
It may need more than one shot at the flushing. Since you're relying on the cleaner coming out of the shutter there's quite a bit that May remain. Sorta like trying to clean a good brush and not get color on the paper towel.
Every Synchro Compur I've had has had sticky slow speeds.
With most of them it has been a bit of oil on the blades and a gentle wipe with a tissue moistened with lighter fluid followed by firing the shutter and gently wiping dry.
This will get the oil of the blades and often makes the shutter come back to life.
They are reliable old things.
I know this is not the completely correct technique nor is it a replacement for a full CLA but it has worked for me on half a dozen cameras which were in good condition but had slightly sticky shutters.
Gentle touch is required though.
Also sewing machine oil isn't really the best...there are some synthetic watch oils that do an excellent job but it's ten times the price of sewing machine oil.