NIKKOR-S Auto, 50mm, loose focus

[User_4754088]

<p>Does anyone have a link to instructions on how to disassemble the rear section of this lens to lubricate and tighten the focus?</p>

<p>I've got a NIKKOR-S Auto 50mm f1.4 lens, early serial number #369XXX that has a loose or sloppy focus. The lens renders beautifully, but is annoying to use after a while because of the slop or looseness in the focus. </p>

<p>When I first got the lens I opened up the front to clean some dust and haze from the inside surfaces, but when I had it apart, I couldn't access the focus section. It's now spotlessly clean, and as I said, it renders beautifully, it's just annoying to use.</p>

<p>If anyone can offer any assistance with this, I'd really appreciate it.</p>

<p>Best,<br>

-Tim</p>

<p> </p>

[rodeo_joe1]

<p>I once had the same issue with a 35mm f/2 Nikkor-O that I bought used. It was a simple fix. The rider that sits in the focus groove had a small set-screw down the middle of it to open it up slightly and take up wear. No modern lens has such future-proofing I fear, and I'm not sure that your 50mm lens will have the same mechanism.</p>

<p>Try removing the bayonet mount and see what can be seen. IIRC the Nikkor-O allowed access to the screw in the rider quite easily, but from the front of the lens after removing the focus grip and the collar around the front group. Greasing the focus helical properly requires a complete mechanical strip-down. I don't recommend that, and chances are the existing lube will be sufficient after the sliding rider is adjusted (if there is one!).</p>

[User_4754088]

<p>Thanks Joe, I'll try that.</p>

[User_4754088]

<p>Hey Joe,</p>

<p>Unfortunately, the NIKKOR-S Auto I have is one of the early ones, and the way they did the mount back then is different from how the later Nikkors were done. You need to take most of the lens apart to get to the screws needed to remove the lens mount. That's what I did, and how I have the lens almost completely apart. Hope I can get it back together again.</p>

<p>If anyone has a PDF for servicing these early Nikkor lenses, I'd love to take a look at it.</p>

<p>Best,<br>

-Tim</p>

[rodeo_joe1]

<blockquote>

<p>" You need to take most of the lens apart to get to the screws needed to remove the lens mount."</p>

</blockquote>

<p>Sorry, but I've never come across that on any Nikkor going back to F era pre-AI lenses. Usually it's just 3, 4 or 5 screws that need to be undone in order to lift the bayonet and baffle assembly off the back of the lens. On early scallop grip Nikkors they used slot-headed screws, and on later ones they used cross-heads. The only issue I've had is that some early lenses used a ball-bearing and spring for the aperture detent. If the aperture ring lifts on such lenses the BB and spring can shoot out and be lost.</p>

<p>It might be that the baffle/element protector is attached internally, in which case you just need to release the 3 small screws that hold the baffle to the mount. Then the Bayonet can be pulled over the baffle.</p>

<p>One odd exception I know of is the 500mm f/8 Reflex-Nikkor, where the bayonet is on a rotating mount and IIRC has no visible attachment screws.</p>

[User_4754088]

<p>Hi Joe,</p>

<p>This is one of the earliest Nikkor-S Auto lenses. If you look at the list of lenses, by serial number and date, and by conversion kit to AI, you'll see that the early lenses like mine have a totally different mount set up. The three slotted screws do remove the baffle from the lens, but removing the baffle doesn't help me get to the focus mechanism.</p>

<p>I've got it completely apart now, just need to clean and re-lube the focus, and get it all back together again, and hope it still works.</p>

<p>Best,<br>

-Tim</p>

[Matthew Currie]

<p>Joe, I also have one of that era, a 28/3.5 from somewhere around 1962. There are no screws in the flange, and it is considered non-convertible to AI.</p>

[User_4754088]

<p>Well that was interesting. Got it all cleaned up, re-lubricated it (with motion picture camera lens lube, which is a bit thicker than SLR lens lube, but it was all I had) and put it all back together again, and much to my relief, it works great. No more slop, nice smooth focus.</p>