Industar 61/26 rebuilding help

[ChrisCummins]

Hey all,
I'm rebuilding a I-61 + I-26 lens for my FED-2, and am having a few problems. I've been using the excellent relubing guide (Matt's classic camera page) but simply do not understand the front lens dissassembly instructions - starting with the 'wait there's more' header. I can't find the long set screw Matt refers to. The only visible set screws are the few in the depth-of-field shrowd.

Secondly, and perhaps insignificant - the I-26M doesn't obey the rules that Matt describes. He says that the helicord limiting screw should contact the rotating barrel at BOTH limits, but it only contacts the limiting screw at one extreme (the 1mtr distance end I think). At the other end (infinity focus) the limiting screw is missed and the only thing stopping the helical barrel from unscrewing fully is the screw above it, as shown in this pic:

By comparison, here's the I-61 also set at infinity distance. Note how the limiting screw hits the helical barrel:

Both lenses at one extreme of focusing movement:

And at the other end of movement:

NOTE: I haven't yet shot a roll with the I-26, so can't confirm focus accuracy.

 

[Ron (Netherlands)]

There should be 3 screws in the depth of field ring. One of them is the longer screw which is referred to in the article. From what I see in your photo's these 3 screws are still left in the ring.

Next step, after you can remove the depth of field ring - i.e. over the front part of the lensmodule, the 2nd screw in the focus module (which can be seen in your pictures in part, becomes fully clear and can be screwed out.

Btw the description of Matt is correct. I have used it with both the I-61 LD and the 26m and it works perfectly. Before fastening the upper screw in your pictures you must find the correct helicoil threads, there are many possibilities to screw the focussing ring back on, but only one is correct. What I did was making pencil markings before unscrewing so you know where to start screwing back. Just try over again until the screws match like Matt describes.

(if you don't succeed, send them to me, and I will CLA these ladies for free) My Industars almost feel like Leica lenses after proper treatment.

 

[ChrisCummins]

Thanks for the tips Ron and for the offer of a CLA!

I will rebuild the I26 as it was when I disassembled it and just make sure to double check infinity focus.

 

[BillBingham2]

You might want to Brian Sweeny our resident Mad Gearhead Scientist.

He has his own forum (left side of the screen, topish).

B2 (;->