AIS Nikkor 50mm f1.4 CLA / Repair
Erm, before we start, this is one lens that require A LOT of patience to put back together correctly. I got this for free and has a lot of mold in it. I’ll show you how to disassemble and HINT you how to put it back together. Once again, putting it together is VERY FRUSTRATING AND TIME CONSUMING. It took me HOURS to get it right. This is not a good tutorial, as I can not show you every single step with photos. So, Don’t do this unless you have pretty good knowledge. But then, read the whole thing top to bottom before you even proceed.
** If you’re creative and skip some steps from below, you can separate all the elements out without taking everything off, if thats your only goal, and It is much easier **
You can see the mold at the rear elements. There are more at the front ones, but lets skip showing you all that. Start with taking out the 3 screws at the mount and pull the mount off.
Now, locate the 2 small philips screws on the SIDE on the aperture ring, take them out and pull the aperture ring out.
There will be 2 screws on the side circled RED, take those 2 screws out and you will free up the stopper between the barrel and the elements, and it can come out. There will be 3 screws that circled yellow take those off might help taking the elements out of the barrel. After the stoppers are gone twist the elements off the barrel. You will have 2 piece falling out with it, one will be the stopper piece, the other one will be what you unscrew the aperture ring from, Which the later part is located on the upper right of the yellow circle on the above photo.
Another view after the lens elements came out. Red circle will be where the stoppers should be at. It will look like the aperture linkage(circled in yellow) except without the Notch. The aperture linkage goes on a tab thats in between the brass piece and the inner piece, look for it before you put it all together, it slides sideways.
Loosen the screw in red circle, and you can twist the whole black piece off that is in the yellow circle. Once you do that the brass piece will come off, showing the actual lens assembly with the aperture. The rear 2 elements will also twisted out at the point.
I took the rear elements off first (remember i didn’t have a manual for it i was just trying, so do it which ever way you want), Now you can separate the 2 rear elements with a spanner wrench.
I already told you how to take the brass coil out 2 steps before, and then you use a spanner wrench to take the front 2 elements from the aperture housing. After that, you figure out a way to twist off the black plastic ring that says Nikon etc, yes it is threaded with glue on one spot. After that the front elements will separate. DO NOT TOUCH ANY SCREWS OUTSIDE THE APERTURE HOUSING. That can mess up your focus/infinity. Especially that big flat head screw to be exact, and if you found out if will focus pass infinity when its fully assemble, go back to that screw.
The rear elements separated.
And the front elements.
Now, do whatever you have to do to clean it. And put everything back together until the lens assembly is ready to insert back to the barrel… And this is the not so fun part that can take hours, especially since I do not know any special tricks for this.
First look at the barrel, put the mount back, locate where is the top of the lens. Make sure the DOT for the focus and aperture scales on the silver right is back on the top. Put one screw back in that silver ring to hold it there.
Now, insert the stopper piece (not the aperture linkage) back to where I said it supposed to go previously. Set the focus to infinity. Twist the lens assembly back on the barrel, if its done correctly, the lens will go in almost all the way, while you can put the 2 Philips screws back(red circle step 3) on the stopper, from the side. Check the focus movement, it should go from minimal to infinity nice and smooth. With no brass showing at minimal distance, on the side, if you mess it up you will see what i am saying.
Now hours later, I assume you got the previous step, or you’re crying, or you’re threw the lens out the window.
Now, you have to twist the lens to minimum focus distance with the lens extend out. Its time to put the aperture linkage in, with that tab from the inside(aperture assembly) fitted into the slot on the linkage, then the whole thing has to go in the slot on the side of the barrel on top for you to screw the aperture ring back on. You might have to loosen the 3 screws on the silver ring (with the dot for aperture and focus scale) to twist the lens assembly out further (don’t twist the whole assembly out or u will be back at square 1), fit that linkage in there , do not hammer it. test the linkage and see if the aperture will go all the way open and close while moving the tab left and right (if it doesn’t that means the tab is not fitted inside the slot). Then you turn all the rings(particular the silver one) back to where its supposed to locate and screw it all back in and check the movement of the focus, it should still go either way smoothly and stops at the correct spot.
Finally, you add the aperture ring , and you put the mount back on and hope it focus to infinity.
If it focus pass infinity (optically, not according to the scale), that means you most have moved that screw outside the aperture assembly I told you not to.
I know its confusing, but its the best i can do, for now.
