Focusing Helicoid: To Lube, or not to Lube?
This is a followup to an older thread that I posted here in November. Basically the focus was slipping and very stiff (close to being stuck). And infinity was at 5m. It was causing problems because the rear element was interfering with my mirror.
Well I finally got a chance to look at the lens this week, and the problem was not too hard to find. The focusing ring WAS slipping, AND the helicoid was placed on the wrong thread. All that needed to be done was a quick adjustment to the helicoid and tightening of the screws/washers.
So while I fixed the actual problem, the lens was still stiff. I figured the grease was old, so I cleaned the helicoids with alcohol and lighter fluid. The lens was pretty much flawless.
This is where my concern lies. I kinda left it that way and put the lens together and it was smooth, BUT I know better, and the threads will be worn out. I bought multi-purpose lithium grease from Canadian Tire today, and I'm wondering how it will work out.
Will Lithium grease make the focusing smoother and looser, or should I just leave it unlubed? I know there are better alternatives, but this is all I have at the moment.
As well, how much grease should I use, and how/where should I apply it? See this image (not mine) for a good reference on what the helicoids on my lens look like. The gold part on the left also slips off so it's actually 3 seperate rings.
For most lenses used at normal temperatures this is the best helicoid lubricant Iíve found.
For lenses used in Arctic temperatures this is a better choice, as it generates less drag, especially in very cold temperatures.
I donít recommend the HG-3000 from Microtools. It generates too much drag for most camera lens applications.
All three of Microtools HG series helicoid greases are made in Japan for the Japanese optical industry and are the best Iíve found for the purpose of lubricating focusing helicoids.
Hmm. So lithium grease is a no-no?
What's the big diff between light and medium? I really like my focus rings really loose for quick adjustment, so will the light work in normal temps too? And how much would I need to apply, and how?
The old grease was thick and disgusting. Someone else must have tried a botched DIY service because it was so gummed up. They probably put too much and in the wrong places. I want to avoid that.
Many people use too much grease. It should be used sparingly.
A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.
~Antoine de Saint-Exupery
Ahh. I did some reading and someone did it with an artist's paintbrush (I have plenty of those!) Like only for the grooves, or the whole thing? Should I lube both rings, or just one? I assume one layer on one ring is enough to give enough space between both sets of threads.
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The main characteristic required for helicoid grease is non-migrating.
It means that the grease does not separate, and stays where you put it. Most greases do not have that characteristic.
Helicoid grease is designed for use with aluminum. Most greases, including lithium and Lubriplate, are designed for steel.
The HG30 from Micro Tools would be a good choice.
That company is the largest supplier of tools and supplies for the camera repair industry.
Use a very small amount of grease. Put a bit at the beginning of the male threads, where they will mate when you assemble it, and a slight bit more further down. Exercise the helicoid through its full range a number of times to distribute the grease. You should end up with a very thin film evenly distributed along its length, in all threads.
BTW, when you disassemble the lens, make marks to indicate the exact alignment of the various parts, and re-assemble it correctly. This matters on some lenses, not on others. If it does on yours, and you didn't make the marks, you're in deep kimchi.
Last edited by Leigh B; 07-20-2011 at 06:37 PM. Click to view previous post history.
Originally Posted by Leigh B
I do use a digital device in my photographic pursuits when necessary.
When someone rags on me for using film, I use a middle digit, upraised.
On a more locally available repair grease option...
I have had good success with using a tiny bit of single touch water faucet mixing cartridge silicone.
Home Depot sells a little bit of it for about $5. A little of this stuff goes a long way.
Mine was originally bought becuase of stiff faucets in my home.
A toothpick worth dabbed onto some old lens threads after freeing them of the dreaded old green grease turned to glue now has them moving very nicely.
my real name, imagine that.
Hmm. Thanks Mike! I'll go check it out.
As for male threads, I assume that would be the smaller silver ring?
Yep, the threads on the outside.
Originally Posted by little-infinity