Jupiter 8 Seating onto Leica 111 Problem

Baybers

Established
Local time
1:23 PM
Joined
Oct 15, 2012
Messages
57
I received my 1957 J-8 lens today and immediately went to mount it on my Leica 111. The lens initially begins to screw on quite easily and then the turns become progressively stiffer until it becomes impossible to complete mounting the lens with about a half turn remaining.
I have Industar 22 and 61d plus a J-12 that have no problems in this regard.
My internet research so far suggests that I may need to find someone to machine an 'undercut' or 'releif thread', if possible, to allow the lens to seat properly?
I have a Zorki 4 and not surprisingly the J-8 mounts beautifully onto this body no problem.
Can anyone help with a possible solution?
My thanks in advance.
 
It seems to happen - the Soviet threads have greater tolerance than German or Japanese ones.

I don't have a cure, other than getting a different lens. Even a useless lens can be a donor for the mount and helical but you will need to reshim for correct focus.
 
The Leica thread is 39 mm in diameter with an RMS thread of 26 turns-per-inch. This is an odd mix of old British thread standard, the Whitworth thread shape, and metric. Some Russian and early Japanese lens makers mistook the thread of approximately 0.977 mm pitch for a 1mm pitch. Attempting to mount these lenses results in what you observed and forcing the issue will result in disaster.
 
The Leica thread is 39 mm in diameter with an RMS thread of 26 turns-per-inch. This is an odd mix of old British thread standard, the Whitworth thread shape, and metric. Some Russian and early Japanese lens makers mistook the thread of approximately 0.977 mm pitch for a 1mm pitch. Attempting to mount these lenses results in what you observed and forcing the issue will result in disaster.

I suspect it's just machines out of tolerance with the Soviets - and the whole system was engineered to cope so it didn't matter. I have a 60's J-8 that works fine on true Leica thread, and a 70's Industar 61-L/D that does not. The FED/Zorki body threads have deeper grooves and the lenses don't firm up until the end while Leica machined their threads to be a tight fit all the way.
 
Hi,

Threads can get damaged or have dirt in them. You can do a rough clean up gently with a brass fine wire brush (like we used on suede shoes years ago) or else run a penknife blade lightly through the turns.

Any decent camera technician ought to be able to check and cure the thread problem. It's not confined to former USSR ones as damage can happen to anything regardless.

As for Soviet standards, the MiG seems to suggest they know what they are doing. Being polite I won't mention the HST...

Regards, David
 
The Leica thread is 39 mm in diameter with an RMS thread of 26 turns-per-inch. This is an odd mix of old British thread standard, the Whitworth thread shape, and metric. Some Russian and early Japanese lens makers mistook the thread of approximately 0.977 mm pitch for a 1mm pitch. Attempting to mount these lenses results in what you observed and forcing the issue will result in disaster.

I suspect it's just machines out of tolerance with the Soviets - and the whole system was engineered to cope so it didn't matter. I have a 60's J-8 that works fine on true Leica thread, and a 70's Industar 61-L/D that does not. The FED/Zorki body threads have deeper grooves and the lenses don't firm up until the end while Leica machined their threads to be a tight fit all the way.

No it's not, JRminox is right actually. It was a choice in early Russian lens manufacturing that was abandoned later on in nearly all factories, while the factory that produced the Industar-61 hung on to the 'old' Russian standard the longest and as a result the Industar-61 lenses are the most troublesome to mount on a Leica or Japanese body.

The soviets didn't do 'machines out of tolerance', their lens manufacturing initially was always done by high standards. Both prewar and early postwar lens production was high quality.

Their machining always was very precise but materials used were of lesser quality and their assembly got sloppier over time. That and the fact that some products weren't 100% compatible with the Leica standards that were used in Europe and Japan has led people to believe that Russian glass is mediocre and cheaply made. While in fact most Russian lenses from the 1950-1980 era can be made into stellar performers with careful adjusting.

After 1980, quality control went haywire in all production stages and as a result you can find lenses with bad lens elements etc in them from 1980 onwards...
 
I accept what you say but the practicality remains the same. The cameras have correct pitch but more slack to cope with variable lens pitches. Most quality Leica copies and Leicas themselves are machined with less slack. Ergo anything can be mounted to a Soviet camera but some Soviet lenses can't be mounted to other cameras.

The real test would be if the off pitch Soviet lenses can be mounted to early Canon RFs.
 
I've had about 5 1950s and early 1960s Jupiter 8s, and they all fit my Canon and Leica cameras. But I do have another FSU, a Industar I think, that doesn't fit. If cleaning both threads doesn't work, just trade it on another one.
 
Opinions here in Oz

Opinions here in Oz

Rang Leica specialists Shutter-Box in Melbourne and without looking they speculated it could be the pitch of the thread and on proper inspection it may be possible to be re-machined.
Three hours away is an older fellow who used to work in the Leica Repair Dept and now runs a small camera repair shop, and his opinion is that like some early Japanese lenses he had seen, the tooling would sometimes result in the thread 'growing' larger toward the lens body. Again, he feels the problem may be fixable.
I want to persevere as the glass is immaculate and the time and money in returning the item, waiting for another and the like, is more than I want to go through at the moment.
My thanks to you all.
 
I actually had an FSU lens (I-26M) that didn't fit on my FSU camera (Zorki 1D). I had to keep working at it, cleaning the threads on both the lens and camera, and repeatedly screwing the lens on just a little bit more each time, until the threads finally cured themselves.

Even inspecting the lens under a magnifying glass didn't reveal where the threads were damaged. I never tried it on my Yashica because I've heard bad things about the skinny RF cam getting lodged in the follower on anything other than an FSU camera. Might just be an optical legend, but it looks easy enough to do.

PF
 
Even inspecting the lens under a magnifying glass didn't reveal where the threads were damaged. I never tried it on my Yashica because I've heard bad things about the skinny RF cam getting lodged in the follower on anything other than an FSU camera. Might just be an optical legend, but it looks easy enough to do.PF

It's no legend. Everytime I've had problems, which was rare, the culprit was the cam getting jammed up. Sometimes the cam will get a slight bit out of adjustment & will fail to align up with the focus ring on the lens. Make sure the focus ring is recessed into the lens b4 screwing it on the camera. I'm sure that you already know this.
 
Not surprising. My J3 threads onto Leicas, Yashicas, Canons, and other cameras, but would not fit on the LTM adapter I use on my X-Pro. My other LTM lenses thread onto the adapter with no problem.

I would hate to be a mechanic who had to work on Soviet cars and other machines. A friend of mine bought a new Russian motorcycle several years ago, a Russian reproduction of a copy of a WWII BMW. Neither of us was heavy enough to kick over the engine, but the two of us finally got it going.

The dealer which sold him the bike told him to run the engine for an hour or so, and then change the oil. We did this, and found the oil to be full of metal shavings and bits. After a few oil changes the shavings eventually disappeared, but it goes to show the amount of precision (very little) that went into Soviet machinery.

20-odd years later, this bike is still running, though it has been pushed for more than a few miles during it's life.
 
A friend of mine bought a new Russian motorcycle several years ago, a Russian reproduction of a copy of a WWII BMW. quote]

Ahh, the Ural - engineered with hammers (& sickles?) 😉

Ural Mars indeed, probably blue and with sidecar. I think I remember that one infuriating problem with these was that the mixture screws were underneath the carbs screwing upwards and, as a result, had a habit of dropping out.
 
Michael,

Wasn't there a risk of getting your leg trapped by the bars that held the chariot on too?

Mixture screw? Just use a sharpened twig !!
 
No it's not, JRminox is right actually. It was a choice in early Russian lens manufacturing that was abandoned later on in nearly all factories, while the factory that produced the Industar-61 hung on to the 'old' Russian standard the longest and as a result the Industar-61 lenses are the most troublesome to mount on a Leica or Japanese body.

The soviets didn't do 'machines out of tolerance', their lens manufacturing initially was always done by high standards. Both prewar and early postwar lens production was high quality.

Their machining always was very precise but materials used were of lesser quality and their assembly got sloppier over time. That and the fact that some products weren't 100% compatible with the Leica standards that were used in Europe and Japan has led people to believe that Russian glass is mediocre and cheaply made. While in fact most Russian lenses from the 1950-1980 era can be made into stellar performers with careful adjusting.

After 1980, quality control went haywire in all production stages and as a result you can find lenses with bad lens elements etc in them from 1980 onwards...

Hi,

And that can be said about a lot of firms that make cameras and a lot of other things. It's called progress by the makers.

I can't help thinking that politics comes into it and we ought to be discussing engineering.

Regards, David
 
Hi,

And that can be said about a lot of firms that make cameras and a lot of other things. It's called progress by the makers.

I can't help thinking that politics comes into it and we ought to be discussing engineering.

Regards, David

No politics anywhere in my post David and also I'm nowhere close to Russia, geographically nor ideologically.

Is there anything regarding engineering (the only scope of my post) that I wrote and you disagree with? I'm always keen to encounter new views
 
The earlier posts are correct about the Soviet thread standards. I trust they know the history better than I. The problem is production. I'm a retired machinist and know that threads need to be made with great care. They are also challenging to measure in a production setting. Usually a thread gauge is used to check the results. The gauges can wear as they need to be used often. The machinery making the threads needs to be high quality, in good shape and reliable. This is not just a Soviet problem. I recently bought a new adapter for Pentax screw lenses to my LTM cameras. It would not screw fully and easily into my IIIc's but would fit my Zorki's and my 1934 Leica II. I mean no disrespect to earlier posters and I'm grateful for them sharing their knowledge. Joe
 
Back
Top Bottom