Industar 50-2 sticky focus

[n6mod]

So my Industar 50-2 showed up the other day, and it's in nice shape, but it feels like the helicoid is dry. (and what you can see of it at infinity focus is certainly dry) It's not stuck, it just sort of binds and frees as you turn it.

What is the collective wisdom on a) getting it apart to lube the helicoid, and b) what lubricant to use?

Thanks-Zandr

[Attila]

Use heat resist material to avoid getting oil on blades at summer time.
_________________


Panasonic G-1
Konica 4/21,2.8/24,2/35,1.8/40,1.7/50,1.8/85,2.8/100,3.2/135,3,5/200,4.5/300,4,5/400
Konica FC-1,FT-1,FP,FM,Pearl,Pear III,Koni-Omega
Please visit my Ebay shop
and my company site
http://webdesign-logo.com

[sichko]

It's very easy to clean the helicoid. It can make a difference and I think that it is worth doing.
_________________
John

[n6mod]

[sichko]

Give me an hour or so - I may have some pictures.
_________________
John

[sichko]

The lens



The focussing ring is held on by three grub screws. These can be loosened or removed to release the ring.



near focus position



infinity focus position



its obvious what to do next



but I chose to remove the bottom ring first



another view



now we've done it



the optical assembly is now turned as if we were focussing beyond infinity. And this is a far as it goes - not very far - a very small part of a turn. This is the position we need as a a reference point when we come to reassemble the lens.



Removal of the optical assembly is easy - you can take reference points on the two parts and, unscrewing very slowly, note where they come apart and after how many turns and/or parts of turns. This is the re-entry point for reassembly. But if you get it wrong you can use trial and error until you get to the position shown above. After removal - three rings and a screw for cleaning. Be careful not to lose the grub screws if they are still present in the rings.



The optical assembly


_________________
John

[piticu]

Great tutorial, Sicko! Thank you! I just bought a Industar-50-2 and this infos might come handy some day
_________________
www.atelierelealbe.eu

[peterqd]

You can buy special grease for lens helicoils from Micro Tools, but it's very expensive. I tried several different greases and ended up using white lithium grease - it's the best viscosity for smooth turning, which it maintains through a wide temperature range.
_________________
Lenses: M42 - CZJ 2.8/20, 2.4/35, 1.8/50, 2.8/50, 3.5/135 - Meyer/Pentacon 1.8/50, 2.8/50, 2.8/135, 4/200
Russian - J8, J9, J21, J37A, M1v, M24m, I50, I50-2, H44-2, H44M, H44M-4, Vega12b
S-M-C Tak 3.5/28, 2.0/35, 1.4/50, 1.8/55, 3.5/135, Super-Tak 3.5/35, 1.4/50, 1.8/55, 2.0/55, 1.9/85, Vivitar WA 2.8/28, Chinon Auto 1.7/55
K-mount : Pentax-M 2.8/28, 1.7/50
Minolta MD : MC W-Rokkor-SG 3.5/28, MC W-Rokkor-HG 2.8/35, MD Rokkor 1.7/50, MD Minolta 2/50, MC Tele Rokkor-QD 3.5/135, Viv W/A 2.8/28
Tamron zooms: SP28-80, SP35-80, SP60-300, 80-210
DSLR: Canon 400D 35mm SLR: Pentax Spotmatic SP, SPII(x2), SPF, ESII, K2, ME Super, P30n - Chinon CE3 - Minolta XG-M, XD7 - Praktica PLC2 - Zenit 3M
Rangefinder: Zorki-4, Beauty Light-o-matic III Medium Format: Yashica-Mat 124G

[n6mod]

John,
Thank you for the excellent photos. I'll pick up some white lithium this weekend and have at it.

-Zandr