Carl Zeiss Jena 135 3.5 diaphragm reassembling 

Thanks! Btw I suggest nitrile gloves for this kind of job. The ones you are having are perfect for shoveling snow.

works also for the flektogon 2.4 35, thanks alot! way less fiddly than some other techniques described on youtube

Thank you very very much. it is very helpfull for me, to repair my pancolar 50mm 1.8 electric. Their aperture mechanisms are identical.

Btw, Pancolar 50mm 1.8 MC is absolutely the same, maybe some other optics too, from this age CZJ.

Great video. But a little question. The diaphragm of the the one I bought is clean, but stuck wide open. Is that a common problem and can I fix it easily without a full reassembling or is it best to disassemble and reassemble?

Many thanks!

Many thanks, very very useful. However, how do you finish reassembling the whole aperture unit? After what you show, there is still a thin ring to be put in place, a black collar closing the whole thing, and the external levers, connecting the aperture to the A/M switch. I can't understand how to put together those, to complete the unit assembly. Thanks.

Thank you my brawer

Thanks this is really helpful, but is it possible that there are some different versions ot the diaphragm? I noticed when you put the whole thing together the plastic part sits flush with the metal housing but mine housing has a gap with a few notches where the aperture blade pins are. Mine is loose and getting stuck around f5.6, i dont know if im doing something wrong or the parts are worn, can i send you some pictures of my housing somewhere? That would really hepl me thanks

Thank you for the video. I'm stuck at the point where I have merged the two pieces together, but when I turn the focus ring, it comes off track? Can you help me out with this?