I'm going to go out on a limb here and offer some generalities that have worked well for me over the years. I most certainly invite others to contribute their experience and opinion to this topic as I have only past personal success to rely on here. As usual, every ol' f@rt will have a conflicting opinion as to what's best but eventually we reach consensus.

I've divided lubricant applications into a few functional categories:

Slow moving parts (things you move with your finger like film advance parts and aperture rings) -- a light grease often recommended for firearms and fishing tackle. Less 'sticky' than Vasoline but does not flow or noticeably thin under the heat of a light bulb or get hard in cold weather..

Fast moving parts (things that 'snap' under spring pressure like shutter drive parts, but not aperture blades) -- A very light household oil like 3-in-1, watchmakers oils, sewing machine oil and rarely, powdered graphite slurry mixed with lighter fluid.

High friction parts (like latch engagements and gear teeth under spring pressure) -- Molybdenum paste.

Aperture blades (things not under pressure but which have 'drag' against adjacent surfaces) -- NO grease or oil! Dry graphite applied by brush or in a lighter fluid slurry. If you can see grain in the graphite it's too coarse. Might be applied directly to the blades using the tip of a very soft lead pencil or rub the pencil lead against a matchbook striker strip. Gently wipe/blow out as much excess as possible after operating the parts to spread the graphite.

Helical focus and zoom threads (a viscous automotive gear or bearing grease) -- ideally you'll have some old threaded barrels to experiment with to get the correct "feel"; it mostly depends on the tolerance in the threads. Something about like extra thick Vasoline usually works OK.

Plastic parts of any kind (you know, THOSE lenses) -- Caution! organic bases and solvents may affect plastics in undesirable ways, read instructions and experiment on junk parts. Plastic-to-plastic is the one area I can recommend silicon-based lubes but light grease is still better IMO.

If a lubricant smells or feels like it might give off volatile vapors of any kind as the solvent/carrier evaporates, or under high temperatures, you can expect that it will probably deposit haze on lens elements over time.

Grease that turns 'runny' under the heat of a light bulb will surely migrate to places you don't want it to when exposed to summertime temperatures. Some older lenses were infamous for this characteristic as revealed by sticky aperture blades and internal haze.

In my experience, WD-40 and similar pressurized fluids are NOT an answer to any camera lubrication problem unless used solely as a penetrating fluid for disassembling corroded parts to be cleaned later.

If you're uncertain as to what's available to you locally, a jeweler/watch/camera repairman, a machinist, gunsmith or a modeller may offer excellent advise regarding easily available products - although you might discuss the above categories with them to ensure they understand your intended application.

A little research on "lubricant-related" search strings including automotive, firearms, fishing tackle, lathes & machining metals, sewing machines, and cameras will be well rewarded.

H2

[Coeurdechene]

Cool post.
Very usefull (if some day i get the courage to mount an atelier with light,tools, and umount and clean one of my older lenses, i'll bear all this in mind).

[tempelorg]

It should say "coarse", not "course". Other than that, great post!

[pentaxpete]

I have been 'lubricating' some 'classic PENTAXES' such as my SV and Spotmatic and Spotmatic F screw models and an ME Super by removing the base-plates and looking at all the parts, small cogs and levers and then in a developing dish I put ONE DROP of Three-in-One Oil ( only Lubricant I have) and touch a piece of electrical Fuse Wire into it and very carefully touch the cogs and levers and a small amount goes in by capillary action and the cameras are much smoother to wind on -- I also cured the infamous 'Canon Squeak' on an A1 I was given .

[Fat Albert]

At the risk of raising the ire of the old thread gods, I'm going to bump this. There's a lot of useful info in the OP which merits further discussion and visibility

[Auzzie-Phoenix]

I'd say tri-flow as an option vs 3-in-1 or sewing machine oil. Tri-flow is light, meant to both penetrate and lubricate, and contains teflon. For most other parts, I'd probably recommend white lithium grease, especially for its resilience against temperature changes.

[fb_penpho]

Has anyone got any experience, good or bad, in using super lube multi purpose grease NLGI grade 2; for the helical groves of a lens assembly. One of it's usual sold combinations is as part 21030 3oz tube.