Philipp500 Posted January 4, 2020 Share Posted January 4, 2020 Hi. I managed to find an original AI conversion kit for my 50 f1,4 nikkor S and followed the steps, removing the rear flange but my aperture ring doesn't bulge from its position. I did remove the single small screw on the side. I'm also wondering about the threaded ring with the 2 tightening notches which came with the kit. Is it supposed to replace the one which is inside the original aperture ring ? Thanks for help. Link to comment Share on other sites More sharing options...
Philipp500 Posted January 4, 2020 Author Share Posted January 4, 2020 I've been tapping on the ring carefully and even tried to wedge a small screwdriver between the ring and the silvery part of the body. Nothing helped. Link to comment Share on other sites More sharing options...
Brian1664876441 Posted January 5, 2020 Share Posted January 5, 2020 Can you post the serial number of your lens? Somewhere in the basement I have a SN list for the conversion kits, from an original Nikon store guide. Link to comment Share on other sites More sharing options...
Philipp500 Posted January 5, 2020 Author Share Posted January 5, 2020 Hi Brian. It's 561130 . Thanks. Link to comment Share on other sites More sharing options...
rodeo_joe1 Posted January 5, 2020 Share Posted January 5, 2020 Sounds like a very early design. That retaining ring was dispensed with fairly early on in the design evolution. The ring may also be cemented in place and need treating with acetone to dissolve some thread-lock adhesive. It's also likely that such a lens uses a spring-loaded ball-bearing for the click-stop mechanism. Be very careful that you don't lose the tiny ball as the aperture ring is pulled off! Link to comment Share on other sites More sharing options...
Brian1664876441 Posted January 5, 2020 Share Posted January 5, 2020 Nikon Lens Versions and Serial Nos I found an online page that shows your lens should take "Ai kit 7", and has 5 flat-head screws. I've done a conversion like this for my 80~200/4.5 zoom that had 5 screws like yours- the ring came off easily. Sounds like some glue or something is holding yours together. I've also done a conversion on a 135/2.8 Nikkor with the same screws, about the same age. Again- came right off. Link to comment Share on other sites More sharing options...
roland_vink Posted January 5, 2020 Share Posted January 5, 2020 Many of the early aperture rings screw onto the lower barrel, a bit like a very finely pitched focus helix - they won't lift out when the lens mounting flange is removed, they have to be screwed off. Once the lens mount and side screw is removed (as you have done) start turning the aperture ring (I think anti-clockwise) and keep turning until it comes right off. I think this is the case for the early Nikkor-S 50/1.4 lenses such as yours in the range 532011 - 635350 which accept AI kit #7. Later on Nikon changed the aperture ring so it can lift out, which is why lenses from 635511 and later use a different AI kit. Assuming you have the correct AI kit, you can confirm this by checking if the inner surface is finely threaded or not. If you are doing your own repairs, I strongly recommend reading the articles here: Lens Repair Articles They give excellent tips on tools and techniques, and even step-by-step guides on disassembling some lenses (including a Nikkor-S 50/1.4 but not the version you have). Good luck! 2 Link to comment Share on other sites More sharing options...
Philipp500 Posted January 6, 2020 Author Share Posted January 6, 2020 Thanks a lot everybody. Right now I don't have the time to re-check, but will do ASAP. I think the scew off anti clockwise should be the solution. Will let you know. Thank you. Link to comment Share on other sites More sharing options...
Philipp500 Posted January 6, 2020 Author Share Posted January 6, 2020 Yes the kit I found IS the AI 7. Link to comment Share on other sites More sharing options...
Philipp500 Posted January 6, 2020 Author Share Posted January 6, 2020 I'll try now to upload some pics. When I turn the aperture ring to unscrew, it just turns around. Link to comment Share on other sites More sharing options...
roland_vink Posted January 6, 2020 Share Posted January 6, 2020 I'll try now to upload some pics. When I turn the aperture ring to unscrew, it just turns around It isn't screwing off at all? The pitch of the threads are very fine, maybe 0.5mm, so a full revolution would only lift the ring a very small amount. It takes multiple turns to come off (assuming it is a screw-on aperture ring). Did you check the inner surface of the AI kit? Is it threaded or smooth? By the way, I have never seen an AI kit for a 50/1.4 lens unless it was taken from another lens, I thought they were all used up years ago. Link to comment Share on other sites More sharing options...
mike_halliwell Posted January 6, 2020 Share Posted January 6, 2020 So, is this a retaining ring or a part of the integral aperture housing? Link to comment Share on other sites More sharing options...
roland_vink Posted January 6, 2020 Share Posted January 6, 2020 I'm pretty sure this inner sleeve does not rotate with the aperture ring. On other Nikkors from the same period it doesn't, the aperture ring turns around it. I believe this is found on early Nikkors with the screw-on aperture ring. On Nikkors from about 1966-67 onwards, aperture ring design changed - the inner sleeve is not there, the aperture ring is thicker instead and does not screw off, it lifts off instead. These lenses need a different AI kit from the earlier models. Link to comment Share on other sites More sharing options...
rodeo_joe1 Posted January 7, 2020 Share Posted January 7, 2020 The slotted ring is what's holding the aperture ring in place. Run some acetone - nail varnish remover - into the thread of the retaining ring to soften any thread lock. This might take a few minutes to work. Next unscrew the slotted ring. Ideally with a specialist tool, or failing that with a pair of needle-nose pliers opened out to fit both slots. Keep a finger between the jaws of the pliers to stop them snapping shut on the lens as you apply twisting force. Better a slightly bruised finger than a scratched lens. That's my opinion anyway! Link to comment Share on other sites More sharing options...
Philipp500 Posted January 7, 2020 Author Share Posted January 7, 2020 Thanks to all of you, I'm now travelling and will have another look in a few days, but yes the ring just turns around (I did many turns) I also tried to loosen the retaining ring, but so far it didn't bulge so I'll try again after the "acetone treatment". Should I put some all around this ring or just a drop here and there ? I don't want some going deeper inside the lens... Thanks again. Link to comment Share on other sites More sharing options...
Philipp500 Posted January 7, 2020 Author Share Posted January 7, 2020 Roland, I bought the kit from Kamerastore.com in Finnland. Old new stock, but they had only one. I'm still looking for kits for the 200/4 and 135/3,5. Link to comment Share on other sites More sharing options...
rodeo_joe1 Posted January 7, 2020 Share Posted January 7, 2020 Should I put some all around this ring... Yes. Acetone evaporates fairly readily, and unless you're really sloppy with it, the chances of it getting where it shouldn't are quite small. However, if you're buying it as nail-varnish remover, check the ingredients to make sure it doesn't contain oil or perfume. I think the cheaper the better in this case. BTW, 'chiselling' at one of the ring slots is a poor way to loosen it, and will more likely only cause damage. You need sustained pressure on both slots evenly to break the thread friction. Link to comment Share on other sites More sharing options...
Philipp500 Posted January 7, 2020 Author Share Posted January 7, 2020 Thanks Rodeo Joe. Will do. Link to comment Share on other sites More sharing options...
orsetto Posted January 14, 2020 Share Posted January 14, 2020 (edited) Fascinating to learn that Nikon actually did make official AI kits for some of their earlier lenses with screwed-on aperture rings! Nikon folklore has long held that all the lenses that were "shut out" of official AI update rings had the screw-on aperture ring design, which allegedly was too much trouble for Nikon service centers to quickly replace and align. Phillipp500, you really found a unicorn with this AI kit: these must have been pretty scarce even back in 1977. Re updating your 135mm and 200mm: be VERY careful and slow doing those, and use your cell phone to snap guide photos at each stage of disassembly. The teles between 135mm and 200mm are MUCH trickier to take apart and re-assemble for AI modification than the 50mm or wider. They have a very long aperture actuation lever that pulls out with the lens mount: this lever can be a huge pain to get precisely back into place (if you don't, the aperture won't function). Take apart and re-assemble the lens at aperture settings most conducive to each step. I did three 135s last year, one f/2.8 and two f/3.5, and IIRC it is easier to remove the mount and extended aperture lever at wide open setting, then re-assemble at minimum setting. You may need a flashlight and magnifying glass to peer into the thin barrel gap to see where you must aim the lever during re-assembly (like the 50mm, it fits between the two arms of a receiving fork). Note this procedure may be different if your 135 and 200 have the same ancient screw-on aperture ring as your 50mm: those always struck me as far too complicated to deal with. Aligning the simpler pull-off aperture ring is difficult enough- I can't imagine futzing with acetone to break Nikon's deadly thread lock, then coping with that inner retaining ring and a spanner wrench (my least favorite tool). Also important: some of the lenses with pull-off aperture rings have tricky mounts where you should only remove four of the five screws, not all of them. The second screw to the right of the mounting notch secures the aperture spring and actuation lever, it doesn't actually hold the mount onto the lens. If you unscrew it, you could lose the spring or nut, and reassembling that bit can be annoying. Edited January 14, 2020 by orsetto Link to comment Share on other sites More sharing options...
Philipp500 Posted January 19, 2020 Author Share Posted January 19, 2020 Hi Orsetto. Thank you very much for your infos. In fact I haven't had the time so far to finish the 50. For the others, I don't have the kits yet. Still looking. Thanks again. Link to comment Share on other sites More sharing options...
JDMvW Posted January 19, 2020 Share Posted January 19, 2020 My solution, NTIM to anybody but me and a few 'purists', was to shoot my non-AI lenses on the 4 non-AI bodies that I have (or on my Canons with an adapter). However, I do approve of the 'kit' for conversion, rather than chopping up the lens. Mr. John White (LINK), by all accounts is the way to go if you don't have the kit. Link to comment Share on other sites More sharing options...
rodeo_joe1 Posted January 19, 2020 Share Posted January 19, 2020 (edited) My solution was to get rid of all my pre-Ai lenses. Most of which were inferior performers to their Ai and Ai-S versions anyway. Certainly WRT image contrast. I did, however, recently convert a pre-Ai 50mm f/2 C Nikkor, using a well-bent (obviously dropped) donor Ai lens to provide the 'factory' conversion ring. Total cost of both lenses was probably less than is being asked for any NOS conversion kit. And does that old 50mm f/2 Nikkor live up to its reputation? Not really, IMO. Edited January 19, 2020 by rodeo_joe|1 Link to comment Share on other sites More sharing options...
rodeo_joe1 Posted January 19, 2020 Share Posted January 19, 2020 Oops, double post. You'd think the 'new' Pnet software would have prevented that. Link to comment Share on other sites More sharing options...
mike_halliwell Posted January 19, 2020 Share Posted January 19, 2020 You'd think the 'new' Pnet software would have prevented that Talking of which...! ...anyone getting the constant page reload of pnet, so it never settles down? or how to fix it! (Win 7 64 bit with Chrome) Link to comment Share on other sites More sharing options...
rodeo_joe1 Posted January 21, 2020 Share Posted January 21, 2020 Talking of which...! ...anyone getting the constant page reload of pnet, so it never settles down? or how to fix it! (Win 7 64 bit with Chrome) I had that issue at first Mike. Then someone suggested a cure that worked for me. All this was shortly after the change to the 'new' look software, which must be a couple of years ago now. IIRC, the answer was to flush the cache of the browser and the Pnet website cookies. This loses your auto-login and a load of other useful stuff. A bit of a pain, but not so irritating as the constant flashing of Pnet's pages. I might have mis-remembered, so please do a search of the site for 'continuous refresh issue' or similar before pulling the chain on your browser cache. 1 Link to comment Share on other sites More sharing options...
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