Lubricant choice (grease) for Krasnogorsk 3

[Jonno85uk]

I'm fixing 2 issues with my K-3 (loop former stuck, footage counter sticky) and after taking off the baffle I can see some parts that use grease. The grease that is there is foul and i'm wondering if there's anything in particular I should choose?

The colour of the grease suggests moly but the colour could be misleading.

 

[shutterfinger]

White lithium is a safe choice but may not last as long as moly. Currently I use Finish Line FETT with teflon and add extra fine powdered graphite if needed.
https://www.amazon.com/Finish-Line-...14463338&sprefix=finish+line+,aps,266&sr=8-12

 

[AgX]

What is the idea behind mixing two dry lubricants (teflon- and graphite-particles)? As this is the first time I hear such.

 

[shutterfinger]

Ever heard of grafitted grease?

 

[AgX]

But instead you are mixing two dry-lubricants.

 

[shutterfinger]

Oh Well. Does this aid the OP?
1 general purpose grease in place of several special purpose greases that covers the special purpose requirements a big +.

 

[Nicholas Lindan]

A general purpose photographic grease, good for helicals and available in several viscosities:
https://www.amazon.com/Japan-Hobby-Herical-grease-JHT9110/dp/B0014ZU03M/
The #10 is rather thin, but is probably your best bet for camera mechanisms.

Another one I like:
https://www.amazon.com/Fomblin-DC976VF-Vacuum-Accessories-vacuum/dp/B003LY0MWI/

A good grease must

• Not outgas
• Not throw off oil with age
• Stay where it is put

Vacuum grease is tops in these areas but it is rather thick.

A typical soap/oil grease, such as lithium or moly, will exhibit outgasing, will seep oil, will harden and will creep and slump. OTOH, lubricating your car with vacuum grease would be a very bad idea.

 

[Jonno85uk]

Thanks for all discussion and ideas, all.

After cleaning (and still in the process of) this camera, I really don't think outgassing is going to be an issue. This thing is filthy. Black, oily, greasy fudge everywhere inside. It's either outgassing or cigarette tar. I've also found a significant amount of aluminium swarf everywhere.

However, knowing how my tub of moly acts, I do not want it in this camera. My moly grease separates out and the oil will get everywhere.

I've got various other special purpose greases (nlgi 00-3, rubber, silicone, marine, etc) and i'm just going to go with a general purpose, nlgi-2 lithium grease that I know doesn't separate and is reasonably tacky.

 

[Nicholas Lindan]

Most oils are distillates of crude oil. They will outgas as their more volatile components evaporate. In their normal usage in cars and machinery this small amount of outgasing is not a problem. But the insides of a camera are a sealed environment and so the vapors get trapped and can condense on surfaces - and for some reason they seem to be particularly attracted to shutters, diaphragms and lenses (something about Mr. Murphy and his various laws). Cameras can go 50 years between lube changes and given this long time the oil and grease will outgas their volatile components until they into tar.

That said, the best bang-for-the-buck oil for lubricating fine mechanisms is Mobil 1 5W. Being a synthetic oil it contains no light volatile components to outgas.

Common lubricating greases are a combination of a soap and an oil. The NLGI number is a measure of viscosity and also a measure of how much pressure needs to be applied before the oil is released. Vacuum greases have poor performance under high pressure loads, unlike lithium and moly greases, so you won't see them in general application. Corning High Vacuum grease is reasonably priced and specified for use in optical assemblies. There are Ultra High Vacuum greases that actually 'ingas' and absorb hydrocarbon vapor - but they are pricey at $100/oz and up.

And with even more said ... the best bang-for-the-buck low outgas/non-tarring grease is -- envelope please -- Mobil 1 grease. (Seems to be lithium grease made with Mobil 1 oil. Mix in a wee bit of M1 oil if you need to thin it out.)