Gun Oil to renew old helicoid grease?

Johanan Pandone · January 17, 2023

Hey guys,

a few years ago I think i had some success getting old nikkors with stiff focus to loosen up by squirting a few drops of gun oil beneath the focus barrel with a small syringe. Problem is, I can't remember which part I squirted it into, (im thinking it's the tiny crack between the front element and the rotating barrel. Any tips or opinions on this? This is not a lens I'm willing to pay to have CLA's but it's also not one I'm willing to open up because I'm intimidated by the extra mechanics of the CRC ***close range correction*** (micro nikkor 105mm 2.8 ais)

Frank Wylie · January 17, 2023

I won't encourage you to squirt any kind of oil down into a lens, period!

If you do decide to give it a go, here's a great tutorial on how to do it: https://richardhaw.com/2017/02/19/repair-micro-nikkor-105mm-f2-8-ai-s/

You can pick up an "Ugly" example of the same lens from KEH Photo for about $90 instead and have a 180 day return guarantee if it isn't up to snuff.

I've used Richard Haw's tutorials on several Pre-AI and AI Nikkors and, as long as you go slow and document what you do, it has worked fine for me.

YMMV

Edited January 17, 2023 by Frank Wylie

Jon O'Brien · January 18, 2023

Sounds feasible to me but there's the very thin 'WD-40'-type oil designed as a moisture inhibitor that comes in a pressure pack that I'd be wary of putting anywhere on a lens - even a drop or two from a syringe. It migrates extremely easily and might find its way to the glass. I think I'd avoid that type of gun oil.

Dom Jaeger · January 18, 2023

It's your lens, so do what you like, but essentially you should never use oil on a lens. Helicoid grease is specifically designed not to seperate and allow oil to migrate. If you squirt oil in, it will travel, especially on warm days. If oil gets on the iris blades it will gum them up (devastating with stills lenses that use a weak spring to close the iris), and it will cause iris reflections. If oil gets on an optic it will cause image degradation and eventually damage the edge blacking. So from a professional lens technician, the advice would be don't do it.

But it sounds like you have nothing to lose if you don't want to pay for a CLA. Where to access the helical is another question, it's unlikely you'll get near it without at least some partial disassembly.

Johanan Pandone · January 18, 2023

Guys thanks for the input. After staring at richard haw's photos for a full day I think i can do the job properly.

Robert Hart · January 19, 2023

Oil on iris blades can be fatal to the iris. The blades may gladwrap to each other, tear apart or pop the tiny rivets which are their pivot axles. You will not feel any resistance in the iris ring when you move it and discover a "goat's-eye" iris later.

Johanan Pandone · January 23, 2023

I was successful in my attempt to dismantle, clean and regrease the helicoids. I put it all back together and it focuses perfectly from infinity to macro, there is just one sport where it's a little stiff I think this is when the CRC helicoid kicks in. may have to take it apart again and rehaul those threads with a lapping compound but right now it works well enough for my use!

Frank Wylie · January 23, 2023

Great! If you used a heavier grade helicoid grease, switch to the lightest one you can find and that may solve the issue you mention...

Johanan Pandone · January 24, 2023

On 1/23/2023 at 10:33 AM, Frank Wylie said:

Great! If you used a heavier grade helicoid grease, switch to the lightest one you can find and that may solve the issue you mention...

because this lens has 3 different helicoids working in tandem, (because of close range correction) I used the lightest grease available (#10) the only thing with a lower viscosity that won't migrate would be a regular household white lithium grease (which I've read is appropriate for stiffer lenses or very fine threads)