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View Full Version : Jupiter-3 Lube Job


Brian
01-09-2010, 07:02 PM
Jupiter-3's are about the best buy in fast fifties for the Leica mount. The best are from the early 1950s, and this lens is no exception.

But like any 50+ year old lens, lubricants dry-up and the action is anything but smooth. This one was very uneven.

This is an easy job, you need some solvent such as Ronsonol, jeweler screwdrivers, and Lithium grease from the local hardware store.

http://ziforums.com/picture.php?albumid=199&pictureid=1912

http://ziforums.com/picture.php?albumid=199&pictureid=1929

http://ziforums.com/picture.php?albumid=199&pictureid=1926

Brian
01-09-2010, 07:02 PM
The optics module simply unscrews from the focus mount.

http://ziforums.com/picture.php?albumid=199&pictureid=1915

Brian
01-09-2010, 07:07 PM
Three small, easy to lose set screws hold the focus ring on. Remove them, and put them carefully in something like an ice-cube tray. "usually" all three set screws are the same size. On this lens, and a few others I've worked on, they are different sizes. Keep them in order. Use the "M" as the start position if you need to keep the screws in separate bins for re-assembly. I did not, and discovered after-the-fact that they were different.

http://ziforums.com/picture.php?albumid=199&pictureid=1916

Under the focus ring you will find one set screw holding the focus mechanism into the mount, or three set screws on later (~1957 and newer). Three is better!

Remove the set screws. The focus mechanism will unscrew from the solid-piece mount.

http://ziforums.com/picture.php?albumid=199&pictureid=1918

http://ziforums.com/picture.php?albumid=199&pictureid=1917

http://ziforums.com/picture.php?albumid=199&pictureid=1922

Brian
01-09-2010, 07:10 PM
Move the focus to the Infinity Position, RF cam fully extended. SCRIBE the two pieces of the helical, as shown.

http://ziforums.com/picture.php?albumid=199&pictureid=1919
http://ziforums.com/picture.php?albumid=199&pictureid=1920

Remove the screws, one on each side, that ride in the guide rail. These screws hold the two-part helical together.

Brian
01-09-2010, 07:13 PM
Unscrew the inner helical.

http://ziforums.com/picture.php?albumid=199&pictureid=1923

Clean the helicals with Ronsonol, Isopropyl Alchohol, or other solvent that you are confortable with.

You also need to flood-clean the outer helical mechanism that controls the near/far focus.

http://ziforums.com/picture.php?albumid=199&pictureid=1925

The focus ring rides on that black rim. You want that ring to turn smoohtly. This one was horrible.

Brian
01-09-2010, 07:17 PM
I clean with Ronsonol, and also use an ultrasonic cleaner for the inner helical.

http://ziforums.com/picture.php?albumid=199&pictureid=1928

Apply the grease, a little dab will do it on a Good J-3. I've seen a couple that require more than others. This amount proved to be too much, and I swab the excess off after screwing the helicals back together. I back them off, and use a Q-Tip to wipe the excess.

http://ziforums.com/picture.php?albumid=199&pictureid=1930

The inner helical has multiple starting points, and only one of them is correct. That's why we scribed the marks before disassembling. Sometimes the marks will be there already from initial assembly.

http://ziforums.com/picture.php?albumid=199&pictureid=1931

Brian
01-09-2010, 07:20 PM
At this point, put all the screws back in order. Screws for the guide rails first; screw the focus mechanism back into the one-piece mount. Put the Set Screw(s) back to hold in the helical. Put the focus ring back on. In the end, all should line up as before: Distance reference point, Distance Scale on the Focus Ring, and Reference Dot for the aperture.

Screw the optics module back in and the reassembly is complete.

http://ziforums.com/picture.php?albumid=199&pictureid=1913

See my other threads on adjusting focus for the Jupiter-3.

peated
11-12-2011, 11:00 PM
Hi there,

Emboldened by Brian's excellent detailed re-lube instructions, I decided to do the same on my newly acquired Jupiter3 today. Getting it apart was easy enough. Cleaned it out good, relubricated, and re-assembled, but the focus is as tight as before. I took it apart once more to inspect and it seems that problem is with the outer helical mechanism that controls the near/far focus (see pic). I've soaked this piece in Ronsonol, twisted it around, re-soaked, etc. but no mater what I do this part still doesn't twist very easily. Do I have a "bad" example, or is there some trick to freeing up this part of the lens?

Brian
12-03-2011, 09:30 AM
On the outer helical, the port with the close-near stop-

I've squirted in Ronsonol, worked it in, sopped it up to get the grease out. Also- the solvent has to dry out of the part for it to be smooth. I've placed some grease in the slot and worked it in. I have not yet needed to take this portion apart, but will on a parts lens and document the procedure.

Brian
12-03-2011, 10:38 AM
Adding a note for the optics module coming out: I have run into Two J-3's that had the optics module glued into the helical. If you use too much force, like "all your might with Rubber pads" to twist: the guide pins that hold the helical together can snap.

SO: if the module does not come out easily enough, leave it in place and disassemble the lens as shown. Once the helical is separated: squirt in a little Ronsonol to weaken the glue, then grasp the inner helical with a mouse pad, then try the optics module again.

I had one that reuqired the glass to come out and the helical to soak in alchohol. The optical fixture was defective on that one.

peated
12-04-2011, 12:27 AM
I worked in some sewing machine oil which seemed to help loosen this part up. Still not as smooth as I think it could be, but much better than it was. I've reassembled everything and I'm happy with the results. Thanks much for your help Brian.


On the outer helical, the port with the close-near stop-

I've squirted in Ronsonol, worked it in, sopped it up to get the grease out. Also- the solvent has to dry out of the part for it to be smooth. I've placed some grease in the slot and worked it in. I have not yet needed to take this portion apart, but will on a parts lens and document the procedure.

Maxklimov
12-20-2011, 08:02 PM
Hi Brian

I contacted you on Z Forums about 1 year ago regarding conversion of Jupiter 8 to work on my M9

Well, you gave me your email but i never got back to you - a lot of stuff happened in my life over the last year

And one of those things that i move to US, Los Angeles, and i am ready to get the conversion done if you still able to help me out with that.

So i tried to email you on that adress you send me over the PM 1 year ago but it doesnt work anymore....

Please if you can still help me out email me on max.klimoff@gmail.com (i again for some reason cant PM you) and i will pay and ship the lens ASAP

Thanks a lot, I will be looking forward for your reply

Max.