28. august 2016

How to fix a squeaky Voigtländer Nokton 40mm f1.4 (S.C) classic

Ha!

I wonder what kind of grease Voigtländer managed to put into this lens!

Image borrowed from
https://www.cameraquest.com

 
My Voigtländer Nokton 40mm f1.4 (S.C) classic has always been tough to focus with, not really a creamy, buttery joy at all, lately it has also begun making squeaking sounds when focusing.
Therefore, I sort of used it less and less and it has been sitting idle for quite a while now.

This is quite a common issue with this lens, from what I gather, but the write-ups online has been rather inadequate for my particular lens, so I made one while fixing mine.



I mean, it's a nice little lens, and sharp too, quite a speed-demon (f1.4) and renders very nicely.


Dog in Prague
Fuji Reala 100
Leica CL, Nokton classic 40 f1.4 S.C

Church, Oslo
Kodak Ektar 100.
Leica CL, Nokton classic 40 f1.4 S.C

Film-crew during the Oslo-marathon.
Kodak Ektar 100.
Leica CL, Nokton classic 40 f1.4 S.C

Wooden bicycle bell(?).
This is as close as you can get at 0.7m.
Kodak Ektar 100.
Leica CL, Nokton classic 40 f1.4 S.C

Man on subway, Tokyo.
Fuji Neopan 1600 in HC-110.
Leica CL, Nokton classic 40 f1.4 S.C

Shop-keeper.
Outside Tsjuki fish-market, Tokyo.
Fuji Neopan 1600 in HC-110.
Leica CL, Nokton classic 40 f1.4 S.C

Anyway, the squeaky issue....yes.....!

This stems from the fact that Voigtländer seem to have been using a lube in the focus-mechanism that dries out, plain and simple.

Not cool!

But, at least it's fixable with a minimum of tools! \o/

Prerequisites:
- The good old t-shirt, brightly colored, to use as a work-surface, it prevents parts from falling and then jump away from you. (usually down to the floor and under something, gone forever, until the vacuum-cleaner eats it on a dreary Tuesday without you even noticing.)

A spanner-wrench:

- Normal to "Small" Screwdriver-set (electronic type will suffice).
- Electronic cleaner, or cleaning alcohol, to remove old and dry grease.
- New lube, I use lithium-grease. Do not use too thick grease, or focus will be too stiff.

All right, here we go.

First, mark the lens-mount, so you will know if you have been able to get the lens back together again correctly. (you will know if your lens is upside-down when you mount it too, but it's cooler to get it back together again correctly before you try mounting it to your camera).

Then you simply remove the 4 screws holding the lens-mount in the lens, screw the lens mount off and then pull the focus-scale off. (wrongly worded on the photo, but you get the idea).
Important note: Try and make a mental note as to where the mount detach from the lens, this will help you getting it back together, it can enter at several different places, so turn, look, pull, turn look and pull, noting where the color-marks are, in relation to the lens (for example the aperture-marker),



Take a moment to observe what you got now.
Below, the lens mount and the focus-scale has been removed.

What you now see, is the stopping notch for the focusing-helicoid, it's aligned with the center-mark on the outer-barrel, good to know.

Yes, you can focus and see how it moves, no danger (yet).


Next, we want to take out the helicoid, since this is the part that makes the squeaky noises.
Now you need the spanner-wrench.
Remove the OUTER retaining ring with the pointy end of the wrench. The inner-ring is to actually open the rear lens-group and we are not doing that now. (mine is clean anyway).


My trick to use the wrench, is to adjust it, place it in the notches, place the lens on the table and twist the lens, not the wrench. It's more secure, but place your hand so that if the wrench slips, it doesn't jump around everywhere -for example around, on-top or over your lens!

Now you can lift off both the focusing handle and the helical.
Please note the following as you do that:
- There is a guide-screw on the rear lens-group. This screw goes into the notch, on the helical shown on the photo below. Take note on how the helical sits in the focusing mechanism.
- The retaining-ring lies inside the helical, after you have lifted the helical out, just twist it upside-down the ring should drop down to the t-shirt.







In my case, I was not able to remove the 4 black screws shown in the below photo.
Annoying as that was (since I was not able to then clean it properly), there are gaps that allow you to clean it somewhat, as well as re-grease).

The screws were simply too tight to budge, so I was screwed in disassembling it. :P


What I did was:
- First rinse and work the lens by using pressurized  electronic-cleaner. This stuff is awesome to remove grease and it dries out without leaving residue. I rinsed, then worked the helical back and fourth and rinsed again etc 2-4 times.
- Then I used pressurized air while working the lens, to make sure the electronic-cleaner was all gone, also while working the helical.
- Finally, I sprayed lithium grease inside the helical, while working the lens 2-3 times.

A final outer cleaning and the helical was smooth and done.

It's not optimal, but I am fairly confident I got out most of the old crap and was able to lubricate the unit properly.


-


Putting the lens back together again is very simple (this whole procedure really is, compared to my former Jupiter-exercises :P ).

However, the final lens-mount is a huge hassle to get mounted on the helical. I don't think I've ever experienced such an annoying issue. (at one point I thought I had messed up the threads and ruined the lens).

The reason for this, is that the threads are made to such an accuracy that you need to get the lens 100% aligned before it enters and that is ¤%¤#¤%&¤ hard.

After 3 hours, I finally found a technique that worked like a charm, this will save you a LOT of time:
See below photo.
NOTE: Do NOT use force, when it enters correctly, it slides in effortlessly!

When trying to mount the lens-mount onto the helical, hold it in your palms.
Then you search for the threads, but screwing the lens anti-clockwise, usually until you hear a click, then you try (carefully) to twist the mount clockwise, to see if it goes in. This is what you normally do when you hold the parts with your fingers, the difference is that you now do it, by holding the parts with your palms.

If it doesn't enter here, continue to twist anti-clockwise further and try again at the next click.

Holding the lens this way, seems to give it much more stability than holding the lens and trying to twist with your fingers.

I could have saved myself 3 hours of agony if I had known this "hold-it-in-your-palms" trick before I started, so you are very welcome :P



Finished!