Jupiter 9 oily aperture. Novel cure.

[E. von Hoegh]

I got a J-9 in Kiev mount, nice clean glass and nice cosmetics. Also, the grease problem - it was squishing and nearly dripping when I got it.
The optics barrel won't unscrew from the focusing mount, I've applied all the (asymmetric) force I dare to with my hands; I need to machine a couple collars to grip the barrels. That machining project will have to wait, and I want to use the lens now.
So, how to dry out an aperture without disassembling it? The grease had separated to two components; one like 30 weight motor oil and one like cold bacon grease. Both stank.
I was able to strip the focusing mount and remove the glass bits; I then soaked it in lacquer thinner. This was working, but not very fast or very well on the thick stuff. So, I decided to boil it in lacquer thinner. Needless to say, I did this outside using a Coleman stove with sheet metal about 12x14 in. over the flame, the lens part was in a small pot with a snug fitting lid. I'd boil, fish it out and actuate the aperture ring - I kept doing this and changing the thinner until the thinner stayed clear. The vapors would flare every so often, but no fire occurred. I lubricated the now bone dry aperture sleeve by blowing some Teflon lube in with compressed air and greased the rest of the lens the normal way.
Guys, I DO NOT RECCOMEND THIS AT ALL!!! Lacquer thinner is extremely flammable and burns purely suck.

I posted it because I think some of you will be amused. And, it worked - there's always more than one way to flay a feline.
Just remember, Ronsonol is a waste of time - boiling lacquer thinner is much more effective.

 

[Dr Croubie]

That's the joy of cheap Ukrainian lenses, you can try out stuff like that and it's not expensive it if borks the lens.
How were the lens coatings and cemented-elements after all that? Still coated and cemented?

 

[E. von Hoegh]

That's the joy of cheap Ukrainian lenses, you can try out stuff like that and it's not expensive it if borks the lens.
How were the lens coatings and cemented-elements after all that? Still coated and cemented?

"I was able to strip the focusing mount and remove the glass bits;"...
The glass and coatings are lovely. I bought this lens because of the grease issue - It was made in 1970 and I'm certain it's never had a screw turned until I got it. More of this FSU stuff is ruined on someone's kitchen table than ever left the factory that way.

 

[Dr Croubie]

Ah, ok, I missed that, only saw "The optics barrel won't unscrew from the focusing mount".
I'd never actually heard about this grease issue, and I've got a whole lot of Soviet lenses. Is it just peculiar to the Jupiter-9? My Jupiter-8 is as smooth as any of my CV and Tak lenses, no grease anywhere.

The only thing I've seen is when I got an Ilex 3X shutter the other day, quite literally dripping when I unwrapped it, but I think that was the seller's misguided attempt at a CLA.

 

[Xmas]

Confused I normally just remove the front optics never had a tight one you undo grub screws?

 

[shutterfinger]

Putting it in a capped container of lacquer thinner and letting it sit over night should achieve the same end result.
Lacquer thinner evaporates quickly also.

 

[E. von Hoegh]

Putting it in a capped container of lacquer thinner and letting it sit over night should achieve the same end result.
Lacquer thinner evaporates quickly also.

The problem was (and still is to a much smaller extent) that the aperture ring is at the very front. This means a sleeve extending back to the aperture mechanism - the problem grease is between this rotating sleeve and the inner barrel that the optics screw into. Just soaking overnight wouldn't work; if you visualize the construction - or are familiar with this lens- you'll see. Boiling it got the solvent percolating through this labyrinth and removed far more grease than soaking for a month would have; the action of the solvent boiling off the hot metal of the parts and the consequent circulation is what moved the grease, heat helped soften the hardened grease as well.
I wasn't looking for a perfect job here, and I wouldn't have done this on someone else's lens. It still needs to be completely disassembled and serviced properly with non-migrating non-outgassing lube such as Krytox.

 

[E. von Hoegh]

Confused I normally just remove the front optics never had a tight one you undo grub screws?

Xmas, you have to unscrew the optics barrel to disassemble the aperture. And yes, grubscrews are the first thing I look for.