Strange Zorki-4 behaviour

[KnipsOmat]

Hi there,

I've got a Zorki-4 here - a 1961 export version not even listed on sovietcams.com - which is behaving quite unusual.

All the slow speeds work perfectly. Including the 1/60s. However, all the fast speeds don't, including the 1/30s and B. I've seen many a broken Zorki-4 where the slow speeds don't work, but this way round? Strange.

On the fast speeds, the first curtain is stuck after travelling about 1/4 across the frame. One can see the second curtain following, the width of the gap changing depending on shutter speed (just as it should be).

Any idea what to look for? As the shutter curtains travel freely across the whole frame on all slow speeds, I would not expect the usual suspects like restrictor gear to be the cause of the problem; I'd rather suspect something on shutter speed selector being wrong.

Cheers,
Andreas

 

[Dez]

That's a good one!

Looks like you need to take the top off. This is dead easy on a Zorki 4, and the problem should be immediately apparent.

The only thing I can think of at the moment is that there is something that has gotten out of place and is impeding the rotating speed-setting cam at higher speeds, but is not in the way at lower speeds. It has been a while now since I have had one of these apart, but in some of the sync'd FSU cameras, the sync mechanism sits forward and to the right of the shutter speed dial, just the right place to cause the interference you mention. It's rather flimsy as well, and may be a good suspect.

Good luck,
Dez