Early Nikkor: DIY hack to AI?

[chris55m]

Congratulations to your successful conversion, and thanks for pointing out the youtube video (the one by Todd Armstrong, I assume).

I have a 1.4/58 myself, and wanted to convert it, partly to make some new photos of the conversion for my AI conversion page yanchep_mike linked above - the old photos were made about 10 years ago on film, and with digital this is much easier. But I tried and could not get the mount off, and could not find instructions how to do it.

So with the video, I'll have another go now. I'm also looking forward to compare the Nikkor to the Voigtlander 1.4/58 on the D600.

 

[Thomaspin]

Look here.

 

[peterm1]

I have replaced a non AI collar / ring with a factory AI ring on a 50mm f2 Nikkor. I picked up the factory converter ring on eBay - there used to be a seller who had a limited range of them but that was several years ago and the popular ones went. It was pretty easy but took a little fiddling to get right - i.e. mainly to disassemble the thing correctly.

I presently have a non AI 135mm f2.8 lens stripped down and ready to cut.


I think that making the cut is the easy bit in some ways. Yes a Dremel tool works fine for that purpose but I plan only to make the vertical side cuts and some intermediate vertical cuts to the correct depth then finish the stock removal with a fine file. So for this job I will use a Dremel cutting wheel and a some needle files. The easy way of finding out where to cut is by getting an AI retaining ring from any lens that has the same maximum aperture - you need to make your cut identical on the "left" end of the slot as described in the link posted in this thread by another poster. It does not matter if the lens you use as a template is of a different focal length so long as the max aperture is the same as the lens you are working on.


Harder than this is working out how to strip down the lens if you have not done it before - e.g. with the 135mm f2.8 the lens had to be focused at either minimum or maximum distance to get the guts out (I can't immediately recall which and am too lazy to get up and go into the workshop to check). Similarly with the 50mm lens - there was a trick to that one as well but it was a few years ago and I cant recall the details. Having said this some lenses are more straight forward, not that anything was too difficult.

BTW it was also important not to move the focus point and aperture when it is stripped to make sure everything goes back as it should.

I use little plastic containers to keep all the bits and pieces safe.

Perhaps the scariest part is marking up the collar/ring to make the cut if you do not have another lens to use as a template.

But there are a couple of web sites around with instructions on how to do this accurately and once you understand the principle involved, in fact its not all that hard if you are adept with fine tools - a metal marking scribe and the like. The other tricky thing is how to hold the ring while cutting it. Being round its a bit hard to clamp. I am planning on making a simple jig out of MDF and clamping that to the table top then clamping the ring to the MDF jig.

My geezer eyes are my biggest constraint these days and I had to buy one of those magnifiers that are mounted on a headband so I can easily see what I am doing. Precision is all of course. As is patience.

 

[Ranchu]

http://rick_oleson.tripod.com/index-107.html

 

[Tejasican]

I got on board of the FX train earlier today, got myself a D600 to power my wedding shoots😎 and I will (for now) primarily shoot MF lenses with it until I can afford an AF lens.

How is the focusing using those lenses on the D600?

 

[CameraQuest]

Hi,

was wondering if anybody has hacked a Pre-AI Nikkor lens to AI themselves?

Should be a pretty simple hack with a Dremel, right?

I'm looking for directions to do this myself on my pre-AI Nikkor 1.4/58mm and 2.5/105mm and all info on how to proceed is welcome!

the problem with DIYS is killing the lens resale value
if the results are not pleasing cosmetically

for DIYS newbies,
getting it done commercially is probably the best solution.

Stephen

 

[johannielscom]

How is the focusing using those lenses on the D600?

It's easy as pie, as long as you remember to switch the electronic rangefinder on in the menu. That will effectively display two triangles and a dot in the status line in your viewfinder, triangles telling you which way to rotate the lens, the dot lights up when you are in focus.

For this to work most effectively I have set the focus array to a single focus point, dead center in the finder. That way, the focusing is totally similar to that of all my 1970's film SLRs: focus through the viewfinders center, then recompose and shoot.

No use for that active 51-point focus array, that's all humdrum. 😀

 

[M Currie]

Late to the party here, I have done several. First of all, I would caution you that this is best done on lenses that are not prime collectibles already. I did a 35/2.8, an 85/1.8 that had been cheap owing to cosmetic damage, a Gauss style 105/2.5 that shows a lot of use, and a 35/2.8 PC. There are web resources that will tell you exaclty where to file or mill to get the indexing right.

I have a "mill drill" machine that I used, chucking a dremel milling tool into it. It went very well, with a couple of caveats.

First of all, one must mill a good part of the meter claw off, because AI meter claws are installed backwards from the earlier ones. It is still all right, but you may end up having to mill off even a little of the screw heads.

Unlike the very easy 35 and 85, the 105 had an extra spring on the aperture ring, which must be unhooked and rehooked. It was pretty hard to do, though not impossible. I don't know whether this is a matter of date or focal length or what, but that spring makes it much harder just to take the ring off, mill it and put it back.

The PC lens, which has no aperture ring, still has a back ring that protrudes and fouls an AI lever. It is extremely easy to take this off, mill, file, or (what I did) turn it down a little, and have 100 percent AI compatibility.

 

[Stdon]

For you brave souls that are converting to Ai here's another modification.

http://www.naturfotograf.com/lens_CPUconversion.html#top

 

[johannielscom]

Thanks, but that's not for me... Decided to let go of my two vintage pre-AI, lenses, I'll be listing them in the classifieds later today...!

But, thanks for posting!


EDIT: They're up now. Just a HU 😉