To adjust or not to adjust... (shutter curtains tension)

Spyderman

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Hi,

I have here those two beautiful cameras Zorki 4 and a FED 3.

The FED has buttery smooth winding, and unbelievably quiet shutter. Once when doing some maintenance I accidentaly completely released the shutter tension springs and had to adjust them from scratch. I don't know if the shutter speeds are accurate, but I much prefer the feel of the shutter as it is now to what it was before. I think it was overtensioned (;)). I tensioned the springs as little as was possible for the shutter to work (about 3.5 rotates on the first curtain and 2.5 on the second)

The Zorki 4 has stiff winding and loud shutter, but I think the shutter speeds are accurate. I know the "don't repair what ain't broken", but I have a strong obsession to release some tension of the springs to make the shutter quieter and winding smoother. But I'm afraid that I might end up with slow fast speeds and like this: :bang:

Should I try it? :confused:

Does the tension affect shutter speeds significantly? I know the curtains always travel at one speed, and the exposure time is varied by variable width of the slit between the curtains. I guess the tension affects the speed at which the curtains travel... am I right?
 
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Hey Spyderman,
Here's my experience with a Zorki 4, FWIW. I got my Zorki 4 about a month ago from a seller in the Ukraine and it was a real mess. Very hard to wind, and the curtains barely moved. I took it apart which meant that I had to adjust the curtains from scratch.

I re-adjusted my curtains so that there is very little tension. The winding is very light and the shutter is quiet. The most significant things I found:
1. Too much tension on the first curtain and winding is really hard. Too little tension on the first curtain and 1/30 will not work all of the time.
2. Too much tension on the second curtain and it will 'cap' at the higher speeds. Too little tension there is over exposure.

Truth be told, in fussing with my shutter curtains, I found that there is very little room for manoeuvre. In fact, my 1/30 only seems to work about 50% of the time, because the first curtain doesn't have enough tension to complete the turn and trip the second curtain.

If your Zorki is winding hard, is it also possible that it is gummed up with old lubricants?

Maybe what you could do is unwind the curtains, but as you slack the tension, count the number of turns it takes to totally ease the tension, that way, you can wind it all back up to where it was if you aren't satisfied.

Cheers,
Kent
 
Kent and I must have purchased the same camera. I just went through the same routine, though I haven't processed the test roll yet to "see" my results. :rolleyes: I have a recently acquired Zorki.4 that had a very stiff wind on. Cleaning and lubing the shaft, bushings and gears associated with the wind knob helped smooth it out significantly (though it's still not as smooth as other FSUs I have.)

You're on the right track. My understanding of the shutter workings is that timing between the two curtains, as you mentioned, getting the lead/follow time of the two curtains correct, makes shutter speeds correct. When tensioned and lubed correctly, your curtains will quiet nicely. The least amount of tension necessary to work properly will prolong the life of the springs and, like on your FED, smooths things out. As you described on your FED is about the starting point I use when adjusting tension. If it works fine there, I leave it. To me, the adjusting is a little tedious and takes some patience for fumbly fingers like mine, but as you've mentioned, it sure makes things nicer.

IMO, cleaning is key. Pay attention to cleaning well everything you can, letting dry and lube again with light oil. This goes for every area of an FSU. That... and patient adjusting... and the Zorki should work out well. I'd go for it.
 
Spyderman said:
Hi,
The Zorki 4 has stiff winding and loud shutter, but I think the shutter speeds are accurate. I know the "don't repair what ain't broken", but I have a strong obsession to release some tension of the springs to make the shutter quieter and winding smoother. But I'm afraid that I might end up with slow fast speeds and like this: :bang:

Should I try it? :confused:

Does the tension affect shutter speeds significantly? I know the curtains always travel at one speed, and the exposure time is varied by variable width of the slit between the curtains. I guess the tension affects the speed at which the curtains travel... am I right?

As reagan pointed out, cleaning and lubrication is first and foremost. Maizenberg's recommendation of 3.5-4 turns MAX for each curtain is pretty much on the spot. I usually start out with 3 turns each and then use Rick Oleson's TV shutter test for fine tuning paying close attention to shutter fade.

Joseph
 
Are there any good on line instructions for Zorki CLA, I have a Zorki 4 with slow/sticky shutter but haven't dared go beyond the rangefinder clean so far.
 
Thanks for encouraging me to do it. I released all the tension, and I tell you it was pretty overtensioned. I counted it. The first curtain had 7 turns, the second had 5.5 turns. I set it to 4 and 2.5 turns and it smoothened right up, as well as the winding. I still have to do the TV test, but the shutter speeds sound good. At first the second curtain would stop somewhere in the middle, but now it runs fine again. Maybe I sould add some tension to the second curtain, or release some ffrom the first, but first I'll do the TV test... Thanks again.
 
Spyderman said:
...and it smoothened right up, as well as the winding.
Good for you. Congrats! A test roll may show some need for tweeking a little, but it won't be much. 7 turns!... eeeyouch!! Bet you heard a sigh of relief from the little rascal. ;)
 
Well done. The TV test proved the shutter is fine, both curtains running at same speeds. I didn't check for absolute accuracy, I just want even exposure - not built in gradual ND filter :) And I must say it's very satisfying to know I've done a good job. :cool:
 
Spyderman said:
"...And I must say it's very satisfying to know I've done a good job." :cool:
Yep, but I must warn you. That is both a blessing and a curse. I now not only buy FSUs, but am not afraid to buy "fixer-upper FSUs." arghhh. :confused: On the other hand, most FSUs are fixer-uppers, so... what the heck. Tinker on, tinker on.
 
CVBLZ4 said:
Yep, but I must warn you. That is both a blessing and a curse. I now not only buy FSUs, but am not afraid to buy "fixer-upper FSUs." arghhh. :confused: On the other hand, most FSUs are fixer-uppers, so... what the heck. Tinker on, tinker on.

Agreed! Before I knew it I was replacing shutter curtains. But I still get stumped sometimes with slow speed mechanisms though, another thing to master.

Joseph
 
I hear ya. Slow speed mechanisms .... arghhh!
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Hehe.. I wanted a RF that was "easier" than my Zorki C... so I buy a Zorki 4k... that I end up lubing the lens, making a new shutter speed dial, lubing/degreasing the film advance, adjusting the rangefinder, and the flash sync...and so on..and so on... :) Ah well, it's all in good fun. My time spent fixing watches sure helps!
 
Does anuyne has a trick to change the overlap of the curtains /without/ having to take appart eh whole shutter ?
I have a Zorki 3 that is otherwise in fantastic shape, but the two curtains don't overlap enough, so there is a light leak when I tension the curtains.

So I realize I ought to take appart the shutter completely to have the main roller on the next/previous sprocket etc, but I sorta chicken out of taking it all out, it takes hours to out back together :D
So, anyone has a trick to fix that problem otherwise ? Wishful thinking ? :D

The Zorki is almost all naked, sitting on my desk begging to get it's clothes back on :D
 
Buze said:
Does anuyne has a trick to change the overlap of the curtains /without/ having to take appart eh whole shutter ?
I have a Zorki 3 that is otherwise in fantastic shape, but the two curtains don't overlap enough, so there is a light leak when I tension the curtains.

So I realize I ought to take appart the shutter completely to have the main roller on the next/previous sprocket etc, but I sorta chicken out of taking it all out, it takes hours to out back together :D
So, anyone has a trick to fix that problem otherwise ? Wishful thinking ? :D

The Zorki is almost all naked, sitting on my desk begging to get it's clothes back on :D

Unfortunately curtains that don't overlap indicate either the shutter curtain was incorrectly installed or was over tightened at some point and the ribbons stretched. Before dismantling the curtain assembly try if 3.5 - 4 turns on each curtain will overlap and will not hang up when fired. If it does you'll have to go all the way with CLA and reinstall the curtain properly.

Joseph
 
"Gah" oh well, I'll have to book a couple hours to do that. At least I'll get to clean the bottom gears completely, thats already something.
And the prospect of having a well honed Zorki 3 afterward :D
 
hello everybody,
I'm not intending to do it by myself, but as the shutter speeds on my Kiev IIIa are getting pretty slow, I'd like to know whether it's possible to adjust it, as it doesn't seems to be as simple as on a Fed/Zorki.
(buze, are you the photim's forum Buze?)
 
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