Jupiter 12 - DIY relube (long w/images)

L

Laika

Guest
This is a basic guide to re-lubing the Jupiter 12 lens (Kiev fit). Many of the Soviet lenses suffer from a stiff focus action with the grease drying out over the years and this easy re-lube should see your J12 working like new.

Tools Required – A set of small screwdrivers and a lens tool/spanner of some kind.

I use a lens tool I bought from www.micro-tools.com but in a pinch you could use a pair of long nose pliers with the tips ground to fit but there is a risk of slipping and marking the optics or lens body. Take care with whatever tool you use.

It’s also a must IMO to work over a tray when stripping down a lens with such small screws. You can use something like a developing tray or kitty litter tray (what I use). I like to have a strip of masking or gaffa tape in the bottom of the tray sticky side up to place the screws on as I pull down a lens or camera, It makes life easy when its time to put everything back together.


1. Unscrew rear element anti-clockwise and put it somewhere where it won’t get scratched.
 
2. Use lens spanner to unscrew the lens/aperture assembly from the front anti clockwise (use the larger of the two rings surrounding the front element). It should come out as one unit, don’t lose any shims that might be on the threaded section of the assembly.
 
3. Press on the back of the section with the locking lugs to compress the internal spring slightly and unscrew and remove the two small screws, carefully slide off the lugged section and watch out for the spring that is under a little tension.
 
4. Unscrew the three small screws holding the focus ring to the lens body and remove it (its not required to remove the screws, loosen them a few turns each will normally do)
 
5. IMPORTANT: Use a screwdriver to mark the lens body section with the tiny grub screws and the very forward section in the same place so the two can be aligned correctly when reassembling.
 
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6. Using a lens spanner unscrew the retaining ring (anti-clockwise) accessible from the back of the lens body and then unscrew the three small screws the focus ring was covering. Now inner assembly should be freed from the body of the lens.
 
7. IMPORTANT: Holding the inner assembly, screw the two sections ‘together’ till they stop and then locate the infinity stop screw. Use a screwdriver to mark the front ring next to the screw and make note of the gap thickness between the two rings (mine was about business card thick). This will allow you to get the two sections back together correctly as there is more than one entry point in the threads.
 
8. Now you can remove the infinity stop screw and unscrew the two sections to access the threads for cleaning.
 
9. Reassembly is in reverse order.



Cleaning and Re-lubing

I’ve found the easiest way to clean the threads is to drop the two parts in something like enamel paint thinners and scrub them with a toothbrush and then let them air dry. I don’t like to use anything like a rag or kitchen towel to dry the threads because they are so fine and even the smallest bit of fluff that gets caught can spoil the silky smooth focus action your after. For thread grease I tend to use something like a high quality, high temp bearing grease. I put a small amount on my finger and smear it on both thread surfaces, carefully screw the sections together and work it in and out a few times and then unscrew it. Check for sections of threads that don’t have grease, dab a little more on and repeat until it all covered. Now wipe off any excess that might have squeezed out of the thread ends and your ready for reassembly.


Reassembly tips

The two threaded section you just re-lubed have four possible thread entry points (my lens anyway) and only one will give you correct alignment. Just carefully screw the two parts together and see how the infinity screw hole, the gap between the rings and the mark you scratched on line up (from section 7). If it’s wrong slowly unscrew the two and just as the threads disengage keep turning just over ¼ of a turn and try again. The key here is not to force anything, be very gentle and you will have more luck catching the threads easily. Note without the infinity screw in place the two sections will not stop at your ‘scratch’ marker so when you think you have it putting the screw will confirm you have got it right.

When you are assembling sections that have three grub (blind) screws like the focus ring make sure the screws are done up evenly or you may find the ring may bind at one section of its travel when focusing.

The lugged section at the rear of the lens can go in two ways; the correct way should have the largest lug at 1 o’clock if you’re looking at the back of the lens (with infinity @ 12 o'clock).

Before I even attempted to re-lube my J12 it didn’t seem to fit the body very well of my Kiev 4AM, it was kinda binding during mounting and removal and after re-lubing it was the same. The problem was solved by undoing the three screws holding the chrome outside mount collar and removing the collar, then I loosened the three grub screws in the chrome collar. Next I just mounted the lens as normal and the collar shifted very slightly but lens clicked into place like I thought it should. I retightened the grub screws and tried mounting and removing the lens a few times… now it fitted very crisply.. I put the outer collar back on and I was finished (the lens and me at the time :D)

I hope this info can be of help to some of you reading this…
 
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Laika, that's a really excellent "How-To" article and you have my thanks for it. Great pictures too. Is there any way you can combine everything into a file (pdf or doc) that people can download? I'd love to save it for another day when I need to take my J-12 apart.

Walker
 
First time I post here, but I like very much to read this forum.
This explanation about the jupiter 12 is very interesting and well done.
I have one question: my jupiter 12 is different type from the one described here, and I tried to unscrew the rear part but it didn't. But I don't understand if I have to force more or it is impossible to unscrew. My question is if I can force more to unscrew or it is impossible to unscrew the back lens in my model.
Ah, forget, my model is the gray jupiter 12 old type that has a different rear part. If someone knows about this, it will be very useful to me.

Thank you in advance.
 
Hello Laika and Season's Greetings from Canada.

I just wanted to thank you for the excellent articles and pics that you posted on the Fed cameras & Jupiter lenses.

Being a bit of a "tinkerer" myself, I currently have a Zorki 4 on my work bench (in pieces) as well as a nice non working Aires IIIc.

The information you have provided will be very usefull.

Thanks again,

Bill K.
 
Using more force, I was able to unscrew the rear lens.
Thank you for this professional and clear tutorial.
 
That's good to hear - mine has your style rear element and I hope to do this over the weekend... :D

William
 
In case you have a grindy old Jupiter 12

In case you have a grindy old Jupiter 12

This is a BUMP for this old thread - I just finished relubing my J-12 and I'm happier now.
 
Hello,

This is a great forum!

This thread is very usefull - does anyone know what has happened to the pictures? They don't seem to showup on my browser :(
 
Hi and welcome!

It looks like the pictures were removed to make room on the server. It's an old thread and attachments (as opposed to photos linked from elsewhere on the web) get periodically cleaned out if older than two years.

I checked Laika's profile; s/he hasn't been posting here in almost three years, so I'm afraid those pictures are gone.

If somebody made their own copies in time, please re-post. I believe you'd be covered under the forum rules to do so.
 
Here's some very similar instructions from the Kiev Survival Site:

http://www3.telus.net/public/rpnchbck/Jupiter-12%20dismantle.html

This is a great site with lots of useful and informative DIY's. Although I would say that re-luing this lens isn't as simple as the OP might have put it, because you'll almost certainly need to be able to check that the lens working distance is correct, which probably isn't a given once you've pulled all the elements apart.

Just screwing the front element out is problematic. I did this with a Trip 35 to rebuild the light meter once. Followed the online instructions. Every photo in the next roll was blurred. Even if it appears to have gone back into the same place, does't mean that it has. Lesson learnt! :D
 
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