Missing frames - Zorki 1

[wolves3012]

I tend to "exercise" the shutters on all my cameras that aren't loaded with film and in use. Recently I noticed that my Zorki 1 would sometimes wind twice, rather like they often do after rewinding. Now, I've also seen other people have this problem, so I thought I'd investigate. More so since this was my first FSU, takes good pictures and I'm rather fond of it.

After pulling the crate out of the shell, I found the cause. The sprocket was wobbly at the bottom end, caused by considerable wear in the lower bearing (the one hiding under the release spring). The bearing is a plain hole in the alloy crate casting and the alloy has worn, allowing the shaft to float and hence the pin on the gear above to foul the pin on the sprocket, causing the double-winds.

Not to be beaten and not to lose an otheriwse-good camera, I pulled the whole thing apart, made a small brass bush and drilled out the worn hole to take it. After some hours (!) getting it all done, it works beautifully with no more double-winds.

Two things then: First, this may be the root cause for others with this problem. Secondly, all of you go get some oil on the bearing before it's too late! You can get to oil it by putting the camera on "rewind" to hold the spring down or by holding the shutter-release down fully for the same effect. The bearing is under the end of the flat shutter-release return spring, in the bottom of the camera.

 

[Xmas]

I second they do need lubing and cleaning.

Noel

 

[fidget]

Good advice. Several of my FSU cams are capable of a double frame wind on. (I've posted about it before). In those that do it, i found that play (or the lack of it) in the wind mechanism, the ratchet gear in particular on my FEDs, allowed this to happen.
I agree that a CLA is always a good idea for these cameras.

Dave..........

 

[ZorkiKat]

Another cause for missing frames, as fidget described it, is in faulty winding break mechanisms in cameras. This part is responsible for stopping the winding action at the right position, and makes sure that it remains there until the exposure is made or the shutter is fired.

This mechanism ensures that the shutter is fully wound so that it opens when fired. Incomplete winding will make the shutter traverse without opening at all.
A faulty brake can cause the wound shutter to backlash a bit- moving the blinds
back from the proper starting position- and will cause it fire blind.

FED-1 and Zorki up to model 4 (?) use spring brakes. When this spring breaks or loosens from its yoke, faulty braking happens. FED-2 and later models used a ratchet to hold the winding gear in place. This ratchet too can loose grip. A recent FED-2 I repaired missed many frames intermittently. Its owner never realised that its brake ratchet was loose.

Incomplete shutter cocking will also cause blank frames. This is often seen in models which use winding levers instead of knobs. This is a common occurence with many FED-3 or -5 and even Zenit SLR cameras. A full wind usually requires a very far throw, much greater than we are used to with other lever-wind cameras. It's usually better to "divide" the single stroke into two or more shorter ones to ensure complete winding and cocking. Even thec contemporary Zenit instruction booklets recommend this action.

Jay

 

[payasam]

Thanks, Wolves. My Zorki 1C gives no trouble, but I think I should do what you advise.