Diagnosis Z - Zorki-1 shutter problems

[merick]

So not knowing much I picked up a Zorki 1 off ebay for a make work project. By that measure a great value. Anyhow I took it all apart, removed film scraps and dried green eastern european grease, replaced the shutter curtains (a full day of entertainment in itself) , lubed judiciously (need to put some grease on the advance gears I think) assembled, and made a pc audio shutter sensor to adjust the curtains and shot a roll of film. $14 lighter (ouch) I return from walgreens in need of some help interpreting the results.

I will attempt to describe what I see. (I could email some pics for someone else to post) 1/100 prints came out okay,maybe a shade darker on the right, but the 1/500 show from left to right, a slim vertical strip of a properly exposed different frame, a 1/2 inch black vertical band sharp on the left and soft on the right, ok picture to about the middle of the picture, fading to black from the middle to the last 1/3 being dark.

What does it mean? How do I fix it?
Thanks!

 

[mooge]

shutter capping - second (closing) curtain catches up to the first (opening) before they cross the film gate. so your shutter tensions aren't right, either the opening needs to be tightened or the closing needs to be loosened. make sure not to overtighten and break the shutter springs.

 

[merick]

That is my suspicion. I was pretty careful not to over tighten things, I started with the opening shutter just enough to trip the second at 1/20 and the second had just enough to work. I didn't take notes from there but I adjusted until my sensor showed ok at 1/100.

Also some washers appeared on the bench during dis-assembly, any idea where they should go? They are probably important.

 

[Ron (Netherlands)]

Also some washers appeared on the bench during dis-assembly, any idea where they should go? They are probably important.

washers can make your gears and axels run smoother, especially at higher shutterspeeds 🙂

didn't you make notes or took pictures during disassembly ? - its not doing any good when parts are left after assembly

 

[AndersG]

Also some washers appeared on the bench during dis-assembly, any idea where they should go? They are probably important.

Uh-oh...
Sometimes they are "just" used as distances, though - my FED 3 had 3 washers stacked under the shutter speed knob - presumably to keep it clear of the top shell - or somebody might just have had 3 washers left at the end of a previous reassembly.. 🙂

Shutter speed knob with washers.

Good job with the shutter cleaning - I never got that far with my FED 3 - I only managed to clean it under the top and to mess up the shutter tensions - will need to return to it at some time.

 

[merick]

didn't you make notes or took pictures during disassembly ? - its not doing any good when parts are left after assembly

I thought I was doing good, laying out removed parts and taking pictures of complicated bits to reference later, when all of the sudden I noticed two washers on the work surface, and later a third. I didn't see what they were on when I removed it and they liberated themselves while I was working. It would have taken one hell of a camera to see the edges when they were in place.

I do believe they go somewhere on one or more of the three shutter rollers, as I recall I put two under the main/combined roller, and the third appeared late in assembly, now residing in a small plastic bag with the old shutter material and my notes. But they could go with the spring rollers, their shafts would move to the side and could have dropped washers unnoticed, maybe one goes under each.

 

[Landshark]

Thin washers seem to appear by magic. Often they're just stuck to the bottom of a gear that you set down.

I know that doesn't help with where they came from. Sorry.
I believe they come from the same dimension that single socks go to vis the dryer and this is is just to keep the universe in balance

 

[rfaspen]

The rise of digital cameras saved my ability to do camera repair. I always take photos during disassembly, lots of them. I do mean lots and from different angles, distances, lighting. The more complex the camera, the more photos. I end up using them for almost every reassembly. If I'm really organized, I assemble the photos in sequence in a folder on my hard drive that's given a name consisting of the camera model and date of work. That way I can locate the project and (sort of) go through the disassembly sequence (or reverse).

Parts left over from a job is a recurring nightmare. Washers can appear from apparetnly nowhere. Using my photos, I was able to determine where a mystery washer came from during disassembly of a M3. It was a *very* thin washer that came from under the brass transfer gear between the film tractor shaft and wind lever gear. It makes/made a difference in the smoothness of the action. With the washer, film winding is like cutting warm butter. The very thin washer stuck to the gear and was not noticable at all. Only when it fell off (without my knowledge) did I find an unaccounted part. That's also one reason why I work on a large white worksurface.

 

[Frontman]

If the washers are very small, then they probably go to the shutter curtain rollers.

I use an old CRT display to set my shutter speeds on these old cameras, it seems to work pretty well. Then I use a digital tester for fine tuning, not that FSU cameras can be tuned very finely...

 

[Steve M.]

Well, as you said, it was sort of an entertainment project. Getting it to work properly is altogether something else. As I'm sure you've found out, there's a LOT of info on the web for adjusting/repairing the shutters, which tells you something about the nature of the beast. Best of luck.

 

[merick]

Entertainment has continued. Second disassembly cycle freed up some more green wax from the stop gear. I finally settled on two washers under the compound roller, and one under the close shutter spring roller.

How many turns of tension would you consider too much? I've been a bit more scientific this time, but the exposure times on the left side (as viewed from the front, continue to be longer than the right side. The open spring moves a lot more mass than the closing one. I've got 6.5 turns open, 3 turns close. at 1/200 speed, .005 being ideal, I test .011 on the left and .007 on the right sides of the field. My math model shows the first train to leave the station needs to move faster, but I don't want to break a spring.

 

[Penny Lane]

Basic set-up for the curtain tensions would be 4 turns on the first (opening) curtain and 3 turns on second (closing). Anything beyond 5 or 5-1/2 turns on the first curtain will (normally) make winding noticeably stiff; I count this as a sign that I'm pushing too far. The entire mechanism, when set up nicely, can operate perfectly smooth.

From there, tweak as necessary. You may find the shutter on the snappy side; if so, drop the tensions a bit. If the shutter doesn't go across reliably on all speeds and in all positions, increase tension (especially second curtain, which is normally set up to be a tad slow). These would be small adjustments to the basic set-up though.

Also, I wonder if your math model is correct, so let's discuss...

You say that you have 0.11s exposure on the left side of the frame and 0.07 on the right. If I take this to be viewed from the film side of the gate (back of camera), you have an opening curtain that is running away from the closing curtain: longer exposure on the left, if viewed from the back, means the gap between the curtains is widening. If this orientation is correct, you need to drop tension on the opening curtain roller.

In any case, first curtain should never need 6-1/2 turns. That's just too much. You'd be surprised how slow the curtains can actually travel across and still give perfectly nice exposures.

Derk

 

[merick]

Thanks to everyone for all the comments so far.

My model works, it is just my interpretation that needed some work. On a spreadsheet I had two trains traveling at speed, the second leaving when the first hit .1 of a mile. Then I could adjust speeds of the first and second train to see qualitatively how that would change their difference in arrival times at stations .25 and .75 miles away. If the first time was longer than the second, the first train needed more speed.

The first reading was always longer than the second and more (too much) spring tension could only close the gap so far. After a nights rest it occurred to me that the two trains need to leave the station closer together, achieved by moving the opening curtain's starting position farther into the drum. In reality it starts further back up the track than the second train anyhow to shield the film when cocking the shutter, it needs to be further back.

Im pretty sure the curtains I took off weren't original by the amount of glue, and I'm using the fed-5 replacement curtains so I was flying blind through all the "carelully copy what was there" parts. The closing curtain needs to be moved back 2-3mm to get out of the frame anyhow, I should just need to make sure the overlap is slightly more.

 

[wolves3012]

I agree with Penny Lane, you have way too much tension. If you did a proper clean and lube on all the bearings, gears, rollers etc the mechanics should be very free-running. I have one Zorki 1 that has only 2 turns opening and 1.5 on closing - it also has a very quiet action. That was probably a best-case example but it gives you an idea of how little tension should be needed with a freshly CLAed mechanism, 4 turns/3 turns should be as far as you need to go. Also, remember it's the slit-width that controls exposure, as long as the basic speed is about 1/30th. Making the curtains run faster, with more tension, will not change that.

Don't obsess too much about the actual speed being exact either, it's a fairly crude & simple shutter and you'll never get it spot-on.

As an aside, the curtains in the later FEDs like the 5 are (personal experience) the worst quality of all and I would simply not use them. Best option is to buy some good quality shutter-cloth and cut your own. It'll probably outlast you, that way.

 

[Ron (Netherlands)]

Further....a Zorki doesn't use washers at the shutter blind rollers. There might be one or two little washers beneath the gear that is at the bottom of the drum. You can try whether the axel of the shutter drum has to much play (moving it vertically up and down). If so, the washers were probably below the drum. Did you get the restrictor gear out ? - there might be a washer too on that gear.

When repairing / servicing a camera I always make (overall) pictures like these: (both from a Zorki 1)
if a little part is jumping away, I can always refer to these overall pictures to see where the screw or washer should go:

gear train

other parts

Disassembled FED 2:

 

[merick]

Having exhausted my patience and attention span I buttoned up this project and put it away for a while.... until now.

I think I can get the timing right if I could get the shutter curtains correctly attached/clocked to the dual drum. Fortunately this information can be provided by anyone with a similar camera without disassembly by only removing their lens and noting the position of the curtain edges in relation to the opening to the film/pressure plate when the shutter is held open with the bulb/z setting. (I think, I'm open to insights).

So if you have a fed/zorki I or similar please observe and report the location of shutter curtain edges in relation to the edges of revealed film when the shutter is held open. Double bonus if your camera is known to have accurate shutter speeds, take good pictures, or be factory original.

 

[Ron (Netherlands)]

Having exhausted my patience and attention span I buttoned up this project and put it away for a while.... until now.

I think I can get the timing right if I could get the shutter curtains correctly attached/clocked to the dual drum. Fortunately this information can be provided by anyone with a similar camera without disassembly by only removing their lens and noting the position of the curtain edges in relation to the opening to the film/pressure plate when the shutter is held open with the bulb/z setting. (I think, I'm open to insights).

So if you have a fed/zorki I or similar please observe and report the location of shutter curtain edges in relation to the edges of revealed film when the shutter is held open. Double bonus if your camera is known to have accurate shutter speeds, take good pictures, or be factory original.

hmm, from this it is not easy to understand what info you are looking for and what you want to do with it. Considering you are in doubt about the correct position of the shutter curtains, this might help (left/right positions when camera with lens opening in front of you):
1. when the shutter is released and the first curtain is closed, its left curtain edge resides at about 3mm from the film gate at the right;
2. after the second curtain closes its right edge overlaps the left edge of the first curtain with 1,5 mm.
If you are in doubt it is a good idea to glue the curtains with double sided tape to the drums before fixing them with contact cement. You can start with one curtain: fix it with double sided tape > close the camera > and run the shutter > if needed, adjust position of the curtain on the drum / roller. Second - remember that only the position of the ribbons of the first curtain and the position of the second curtain on the drum are important in this respect > there is no exact position on the rollers. However the trick is to get the edges of the two curtains precisely right-angled.


NKDV FED repair & cla XIV by Ron (Netherlands), on Flickr

 

[batterytypehah!]

Threads like this, and another ongoing one, explain why my own Zorki-1 is still in pieces... (see also current signature)

If it's of any help, I'm reasonably sure mine was original and unmolested until it got dragged in the sand behind a galloping horse for a few miles, then put away for a couple of decades to allow the dust to cake, and the curtains to stiffen. They are still attached to the drums and ribbons and I'll gladly measure the whole mess for you, if you think it makes sense. Might only confuse matters more, though.

 

[merick]

I am indeed attempting to identify the correct attachment of the curtains to the drum, specifically the precise alignment, so that shutter timing adjustment is within the range of fine adjustment made by tension the spring rollers. I will attempt to clarify;

On the bulb or "z" setting fire and hold the shutter release as if taking a long exposure, so that the film would be exposed. The opening curtain is open, or has traversed to it's final position, and the closing curtain has not moved yet. Note or measure if possible the edge of each shutter curtain's position to the edge of the film window.

 

[Penny Lane]

Here's something that might help, but in a different way (so skip this if you fear it may confuse you further):

The drum and pulleys on the main axle are of slightly different sizes, the pulleys having a slightly larger diameter. This means that on winding the shutter, the first curtain catches up with the second curtain. The common mistake made, is to overlap the steel end strips completely when building up the shutter from scratch and working with the loose rollers (i.e. not in their normal places in the shutter crate). What happens in this case, is that the overlap is too much by the time the shutter is wound.

What I do is this (though others may prefer different methods, and I may at some point, too): I hook up all the various bits where they should go, having minimal overlap on the end strips. Then, with a blocking pin in the drum and rollers and those set to correspond correctly, I find the correct positions on the drum, pulleys and rollers for all the curtains and ribbons.

Then when installing the whole shutter/ribbon/roller system, I work from a wound starting position (as per Jay Javier's FED/Zorki Survival Site), with the end strips just clearing the film gate. Mind though that no-one says it's not fiddly as anything, but I dare say you already noticed that 🙂

If from this position the curtains complete their travel reliably, you're in the ballpark. Tweaking the roller tensions should get you to a point where the shutter performs as good as it would normally get. Try not to go all-out on extreme timing precision though, it really is rather a simple mechanism and 'close' is all you're ever going to get it - or maybe, with lots of patience, even 'very close'. It sort of goes with the territory with these Barnack-type shutters 🙂 Best way to check if you're close enough is, when it's all together and working well, to shoot a roll and see what happens.

Let us know if you're getting decent results!

Derk