 Posted: Tue Feb 23, 2016 6:32 pm Post subject: Cleaning oily Nikkor 50 1.8AiS pancake |
 |
|
dbmn wrote:
Dear mflenses,
I just recently cleaned the oily aperture blades of a Nikkor 50 1.8 AiS (Pancake Version).
It was the first time that I ever cleaned oily aperture blades but it went surprisingly well. I wanted to share with you, what I did 
First I tried to reach the aperture blades.
Dont go down the rabbit hole and remove the helicoid. It is not necessary to do so (btw I did and regreased it, while I was at it, but it is not worth the hassle to just clean the blades).
To remove the front element, simply turn your lens to its nearest setting (0.45m) and a tiny screw will appear as in the picture. I used a flathead 1mm Screwdriver to LOOSEN it. DO NOT REMOVE IT COMPLETELY!
After loosening the screw, you should be able to remove the front element in a counterclockwise movement.
As can be seen in the following picture I left the screw in the element. I do this, whenever possible, because this tiny screws are a pain to put back, if fully removed. Usually it is enough to loosen it just a bit, to be able to turn the element.
In a next step, use your spanners to remove the lens element.
I tend to wrap my elements in a piece of paper, while i'm working on the other parts...
Next you need to get the apperture mechanism out.
To do this, two screws (I THINK they were JIS#0, but i'm not 100% sure) need to be loosened. Put the screws away to easily find them again. I use old Film Boxes for this.
To get the aperture mechanism out of the lens can be tricky, because it tends to get stuck. I applied gentle force to both blue markings with a screwdriver and was able to pull the mechanism out milieter by milimeter.
Btw you can see the aperture control curve (is that the english word?) in the green circle. This strangely shaped piece converts your linear apperture command in the actual aperture opening or radius.
Next is the cleaning step.
I decided, that I didnt want to take apart each blade individually and thought it might be a good idea to clean the whole thing as one. If it in fact was a good idea, I can tell you in half a year (when the oil came back, or not). But for now it worked.
To clean it, I put the whole mechanism in a glass jar filled with petrol / ethanol and moved the aperture opening/closing lever with some tweezers at least 20 times (maybe more).
I then took it out of the petrol and tried to dry the aperture blades in my hand.
This went surprisingly well by moving the blades a littel more and waiting for the ethanol to evaporate on the blades (takes < 5 sec). You might need to repeat this step for another 20 times, because some ethanol builds up in the mechanism and you need to get it out by repeated movement of the blades.
At some point the blades will be "dry" when you move them a couple times.
The reassebly is not too difficult, because basically everything screws nicely back together. The only thing I had trouble with, was putting back the apperture mechanism in the lens. This is because the notch for the aperture ring and the aperture setter (spring thingy) need to fit. Space is quite confined and you dont see much.
After some (acutally a lot) of trial an error, I found it the easiest way to keep the apperture mechanism in your left hand while lowering the lens in your right hand. Try to peek into the lens and adjust the long lever (spring thingy) first. The second, shorter lever can then easily be adjusted by turing the aperture dial on the lens. You can actually test both functions of the lens in that state already.
If all is in place, push the mechanism down completely.
After this comes the easy part. 2 Screws back in, Attach front element, close with Spanner, add top element, tigthen the tiny screw that you left in the top element.
That's it.
This was how I cleaned my lens. So far it works perfectly and I am very happy how it turned out.
I have to admit, many of the things were quite freestyle with to real planning but I learned a lot in the process.
If you have any suggestions, how to do things correctly or better, please share them
Best
dbmn |
Search
Memberlist
Register
Profile
Log in to check your private messages
Log in
