A 4k being a bit of a strange one

[Sega]

Hopefully some more experianced brains can help me on this one as it doesn't quite seem to match the stickies and googling a solution acctually bought me here.

Due to an injury I've had a little more time recently to go over my Kit and bought a couple of project bodies to act as back ups to my main one, a 4 and 4k spares repairs condition unknown.
The 4 had the usual stickyness and the rangefinder was stuck but with some gentle cleaning, lubrication and movements it is as good as new but the 4k was a different story.

It fired straight away, slow speeds initially didnt work but clean and lube they now do bar 1/30.
1/30 behaves like bulb and I know its not a case of selector in the wrong spot as put it into bulb mode and it behaves normal and holds shutter till button released as it should.
Now while the speeds all work the final travel seems to be a couple of mm short when compared to my known good ones, the curtains also look a little slack, there was also some loose light seal matirial trapped in the bottom channel.
As with most of my projects theres 0 history (keeps things cheap and cheerful) and there was some surface rust inside the camera that cleaned off with a little oil.

I can adjust stuff but will I be looking at needing to source parts for it?

Work doesn't fase me nor does taking it apart as I wanted to do a little cosmetic customisation aswell.

Thanks in advance.

 

[Ko.Fe.]

If you need parts, by second unit for parts. This is the only way parts are available.
If you need curtains they are sold as parts on eBay. Or as the curtain material to cut.

 

[Sega]

Thats the thing, will parts be needed?

It's behaviour does not match what I can find as technically it works, the slow speed mech winds and seems to keep rough time on everything bar 1/30, the curtains are slacker than normal, but under high powered LED light I can't make out any leaks and travel is just a few mm out.

For parts I can make or get made some by using the good spare 4 as a template, I just want to be sure of what I need before I start so I don't accidently lose anything or forget where something important goes

 

[xayraa33]

A few things to consider, If the 2nd shutter curtain never releases, then it could be due to a pair of faults. The 2nd curtain latch arm which is the bent-shaped arm close to the speed change mechanism. It should be under tension pressure inwards and downwards and when you press the shutter release button... it should go downward movement wise.

Another problem maker is the latch operated by the slow-speed escapement cam. If that is stuck or or the slow-speed escapement is placed in wrong or slightly askew during re-assembly or when tinkered with, then it will block the second curtain from releasing and the shutter will act as it is on "B", for bulb.

 

[Sega]

The Curtain definately releases, both move normally but 1st stops just a few mm short and the second meets it as it would if it had gone all the way, no gaps, and if you gently push they will go past the point it sticks and in normally.

I'd try and capture it on video but its diffucult to catch it on my current smartphone.

 

[xayraa33]

The Curtain definately releases, both move normally but 1st stops just a few mm short and the second meets it as it would if it had gone all the way, no gaps, and if you gently push they will go past the point it sticks and in normally.

I'd try and capture it on video but its diffucult to catch it on my current smartphone.

Did you muck about with the shutter curtain bounce brake that is at the bottom of the camera by any chance?

 

[Sega]

Haven't touched it yet, just did a gentle clean and oil without disassembly to try and access its condition.
Only adjustments so far was the mirror as it was quite far out and I only did that via the access hole on the front.

 

[xayraa33]

If you do plan on taking the top off your Zorki 4k, it is a little more fussy than the Zorki 4 due to that coiled spring under the film advance lever.

It has been a few years since I worked on a Zorki 4k but there was a way to pin the spring before it unravels on you during dis-assembly.

Putting that spring back in was no joy either. It has to be coiled tight or the top cover does not go on or it will go on fitting improperly.

 

[Sega]

I'll only remove it if absolutely nessasary, as with all my vintage projects I don't like opening anything more than I have to to avoid damage to anything that has fatigued with age.

I've taken a couple of pictures on my old Nokia 1020 as its macro is fairly good to try and show a bit more of what the curtains are like vs the healthy spare 4, I'll post them as soon as I figure out how to get them on here.

 

[Sega]

Hopefully these work, the top 72 is the healthy, the 75 is the 4k, you can just about see the slackness in the Cocked and Fired files, the Bulb stop is to show where 1st curtain stops

 

[wolves3012]

There's a sticky thread here for the 4/4K CLA, which I wrote some years back:

https://www.rangefinderforum.com/forums/showthread.php?t=33914

Please read it before you contemplate removing the top cover, otherwise the dreaded spring WILL uncoil on you!

As for your problem, I suspect that either there's too much tension on the shutter latch arm (the crescent-shaped part, see the sticky) or there's a lack of tension on the curtains or there's something catching in the mechanics - such as the curtain laths against the frame or light guards. You can bend the latch spring a little to de-tension it but it'll be very, very little I'd suggest, if that is the problem (and no, it isn't uncommon to need adjusting).

I do have a few parts salvaged from Zorki 4/4K, it's possible I could have what you need if you're stuck for something. Send me a PM if I can help out there.

 

[Sega]

Thank you, I did have a read before to see if it could help point to the cause.
I'll try adjusting the tentsion, could this be the cause for 1/30 acting like Bulb as well?

 

[xayraa33]

Thank you, I did have a read before to see if it could help point to the cause.
I'll try adjusting the tentsion, could this be the cause for 1/30 acting like Bulb as well?

If there is not enough tension to drive the 1st curtain then there might be not enough momentum to release the 2nd shutter curtain.

I remember pawn shop owners in the past would over tension both shutter curtains on Leicas and their copies for sale, so the shutter does not stick on the slower speeds.

This was due to the cameras needing a proper CLA and these pawn shop owners wanted a quick fix to make the cameras sellable to the casual inspection by a prospective buyer, but it usually threw the shutter speeds off spec in the process and introduced shutter capping on the higher speeds and even introduced shutter curtain bounce in some cases.

 

[Sega]

If there is not enough tension to drive the 1st curtain then there might be not enough momentum to release the 2nd shutter curtain.

I remember pawn shop owners in the past would over tension both shutter curtains on Leicas and their copies for sale, so the shutter does not stick on the slower speeds.

This was due to the cameras needing a proper CLA and these pawn shop owners wanted a quick fix to make the cameras sellable to the casual inspection by a prospective buyer, but it usually threw the shutter speeds off spec in the process and introduced shutter capping on the higher speeds and even introduced shutter curtain bounce in some cases.

The thing is they both drive fine, speeds match best I can tell to a healthy Camera without more specialist kit, even the slow ones, theres no hesitation on firing or when moving across until it stops about 3mm before it should as shown in the 3rd attachment, and shutter 2 stops as it would on the overlap of shutter 1 if it gone all the way, if you gently get shutter 1 to complete its full travel shutter 2 will meet it there as well.

The timing mechanism can be heard winding on all slow speeds except 1/30, its behaviour is identical to even the bulb on the healthy body, it releases only when shutter is depressed, all other speeds it will do it on it's own without issue.

Given the rust it had and the seller not knowing how it works (I take this truthfully too as I paid a pittance for it) I'd be pretty sure its never seen any adjustment since 1975, it also lacks any of the wear marks my '67 4 has so its probably seen little use, at a guess it was probably bought and maybe saw use for a year before being chucked aside without care as it lacked case and lens.

 

[wolves3012]

Not sure I'm following the problem correctly here. 1/30th isn't a 'slow' speed on the 4K (although, oddly, 1/60th is!), the slow-speed escapement isn't involved at all at 1/30th.

Are you saying 1/30th acts exactly the same as 'B'? In other words, the first curtain opens when you press the shutter but the second curtain doesn't close until you release the button? I have had cameras where only one of the 'fast' speeds doesn't work properly - a Zorki 5 I own failed to work only on 1/250th, for example - due to incorrect curtain-latch spring tension.

 

[Sega]

Sorry I got it wrong with the noise, you were right though on Tension as I've just got in and adjusted it and 1/30 is back and some of the slacks gone, light seals were also rotten and had gummed a little further in so I'll have to buy some fresh ones, I'm guessing its been wet for prolonged time.

I have however managed to lose a screw due to the awkward way I have to work atm (My lower back has gone so I have to sit in a chair and work from a lap tray), its one from the whats called the front cover plate on here http://rick_oleson.tripod.com/index-58.html , left hand recess on the ring that I think holds the left hand light baffle, I'd be happy to buy some replacements if you have them in your spares Wolves.

I'll leave it in bits for now to make it easier to get the seals in and do the cosmetic work.

 

[Sega]

Found the screw 😀