Vintage Gear Surprise, pre AI.

[Eb]

Congratulations! What a nice product shot as well

Thanks, Erik.  It was just a quickie shot by filtered window light.  A bit too much cropped off the bottom, but easily fixed, if so inclined.  May have been my first shot in a year.  But, it felt so good!

[Eb]

Here are a couple of sheets on the 400/5.6 P-C and AI...
Dave

Thanks Dave!  That is good information embedded in the marketese lingo.  I like!

[Matthew Currie]

Eb, yes, I enjoyed my IF version of Ai Nikkor 400/5.6 ED on D610.  Unfortunately I sold it and am not sure how it mates with D810, but I've heard that the non-IF version uses also ED glasses and its optical performance is better than IF.  So, I'm pretty sure it will serve you nicely.

I have the non-IF AI version of this lens, and if the pre-AI is the same internally, then I doubt it will disappoint unless it's broken.  The long focus throw makes it hard to follow action, but deadly accurate when you can, and it's nice and sharp.

[jhinkey]

I have the non-IF AI version of this lens, and if the pre-AI is the same internally, then I doubt it will disappoint unless it's broken.  The long focus throw makes it hard to follow action, but deadly accurate when you can, and it's nice and sharp.

Yep, my two 400/5.6 ED AI (non-IF) copies are excellent on my D800 (when I can focus it accurately) and my A7RII.  A pre-AI version has always been on my list of lenses to look out for, but to use and to just marvel at.

Congrats on the find.

[Eb]

The #55 conversion ring arrived today.  But, I'm stymied with removing the small philips screws holding the chrome flange to the lens.  The best fit screwdriver is a 00x40, which is rather diminutive.  The shaft just flexes with effort and I'm concerned about stripping the screw head.  After applying heat with a soldering iron 10-15 seconds, there seems to be no release of the screw at all.  It appears, after over 40 years, the weld is rather persistent.  At this point, I feel brute force is not an option.  Are there any suggestions on how to proceed?

Edit:  Penetrating oil an option and or lots of heat?

[Hugh_3170]

Apply a small amount of solvent such as acetone to the first screw and wait for up to say 15 minutes until any thread locker softens,  repeating several times if needed, until the screw yields. 

Then repeat on a screw by screw basis for the other screws. 

You can use nail varnish as a thread locker for reassembly purposes.

Try and keep the solvent off any areas that are painted in case the paint suffers. 

Hope this helps - not a fast process, but one that should minimise damge to the screws.

Edit:  The small Philips screws are more likely to be JIS screws, so make sure that your cross head screw drivers are JIS compatible, else head stripping is likely.  JIS screwdrivers seat better into JIS screw heads than do Philips.  Micro-Tools can supply JIS drivers.

[Erik Lund]

You need a JIS screwdriver #0
A strong workbench as support, stand up so you can put your weight directly over the lens/screwdriver a lot of down-force is needed!
wear thin rubber working gloves
loosen with a drop of acetone
You might try torque in the tightening direction to work it loose
Have a small break in-between screws
Don't relax when you get to the last one! Keep the down-force high

[Eb]

Apply a small amount of solvent such as acetone to the first screw and wait for up to say 15 minutes until any thread locker softens,  repeating several times if needed, until the screw yields. 

Then repeat on a screw by screw basis for the other screws. 

You can use nail varnish as a thread locker for reassembly purposes.

Try and keep the solvent off any areas that are painted in case the paint suffers. 

Hope this helps - not a fast process, but one that should minimise damge to the screws.

Edit:  The small Philips screws are more likely to be JIS screws, so make sure that your cross head screw drivers are JIS compatible, else head stripping is likely.  JIS screwdrivers seat better into JIS screw heads than do Philips.  Micro-Tools can supply JIS drivers.

You need a JIS screwdriver #0
A strong workbench as support, stand up so you can put your weight directly over the lens/screwdriver a lot of down-force is needed!
wear thin rubber working gloves
loosen with a drop of acetone
You might try torque in the tightening direction to work it loose
Have a small break in-between screws
Don't relax when you get to the last one! Keep the down-force high

Thanks to both of you, Erik and Hugh!  You have pointed to my nearly fatal error of using a philips driver.  I will now be on the hunt for a JIS #0.  The acetone idea and a surfeit of patience might just do the trick. 

Just out of interest, have you ever had to deal with a broken screw?

[Erik Lund]

Sure they can break, the head can come off but that is very rare.


With this bit style it is easy to make a mess out of the head,,, so take care - also the screwdriver must be in line the screw axis at all times!

[David H. Hartman]

A camera repairman friend use to use a portable butaine soldering iron to soften the thread lock on manual focus Nikkors. I've used acetone. The thread locker is high temperature Loctite.

If the screwdriver fits well and is strong enough one can torque the head of the screw [without acetone or heat]. I did that once. I managed to extract that screw. I drilled it with pin vice. Jammed a larger bit into it and screwed it into the lens. The somehow removed it from the bit.

Never, never never again! Always ask someone who knows.

Dave Hartman

[richardHaw]

i almost always do not require the acetone or torch routine anymore

what I do is use a long JIS screw for torque and use pressure from my palm and power from my elbows and wrists to do the trick.

the heads will come off at times but never on the bayonet screws in my experience, it happens more with cone flush head screws more. happened to me 2-3x now. good thing i have the handy screw extractor bit that i believe is only sold here in Japan in stores but can now be bought on eBay.

https://richardhaw.com/2015/12/29/best-practices-part-1/

this is kind of old and in serious need of an update, which I will do in my new year's vacation

cross head screws are not so bad it's the (-) screws that are a bit tricky at times.

[Eb]

i almost always do not require the acetone or torch routine anymore

what I do is use a long JIS screw for torque and use pressure from my palm and power from my elbows and wrists to do the trick.

the heads will come off at times but never on the bayonet screws in my experience, it happens more with cone flush head screws more. happened to me 2-3x now. good thing i have the handy screw extractor bit that i believe is only sold here in Japan in stores but can now be bought on eBay.

https://richardhaw.com/2015/12/29/best-practices-part-1/

this is kind of old and in serious need of an update, which I will do in my new year's vacation

cross head screws are not so bad it's the (-) screws that are a bit tricky at times.

The first hurtle is down.  I located a screw driver set with JIS bits.  Don't like that as much as I would like one with a rigid shaft.  The set comes with a supplementary long shaft, as well.  I was lucky to get anything at all in our town.  Mention JIS and all shop employees gave incredulous looks.  I suppose I could have ordered from amazon, if not now on a roll.  Actually, this set is nice, but pricey, as it contains bits for all kinds of electronics gear.  I got a can of pure acetone, lifetime supply, after finding that the nail care type I had on hand is adulterated.

As a former amateur gun smith, I've extracted my fair share of broken screws, yet, on a lens, this would seem daunting - nerve, comes from experience - me thinks!

I think I will get it done, but there are some other things to do for what remains of this day.   Your site is very informative, Richard!

[richardHaw]

The first hurtle is down.  I located a screw driver set with JIS bits.  Don't like that as much as I would like one with a rigid shaft.  The set comes with a supplementary long shaft, as well.  I was lucky to get anything at all in our town.  Mention JIS and all shop employees gave incredulous looks.  I suppose I could have ordered from amazon, if not now on a roll.  Actually, this set is nice, but pricey, as it contains bits for all kinds of electronics gear.  I got a can of pure acetone, lifetime supply, after finding that the nail care type I had on hand is adulterated.

As a former amateur gun smith, I've extracted my fair share of broken screws, yet, on a lens, this would seem daunting - nerve, comes from experience - me thinks!

I think I will get it done, but there are some other things to do for what remains of this day.   Your site is very informative, Richard!

glad that you liked it
what's the smallest screw usually found on a gun? M2 I would presume? If it is the screw extractor that I was raving all about will come in handy up to 1.1mm 

gun repair has a lot in common with lens repair. a hobbyist friend of mine cleans guns for fun and the same philosophies apply most of the time like not applying too much grease,etc

[Akira]

gun repair has a lot in common with lens repair. a hobbyist friend of mine cleans guns for fun and the same philosophies apply most of the time like not applying too much grease,etc

Yeah, both are used to shoot something.   

[Eb]

glad that you liked it
what's the smallest screw usually found on a gun? M2 I would presume? If it is the screw extractor that I was raving all about will come in handy up to 1.1mm 

gun repair has a lot in common with lens repair. a hobbyist friend of mine cleans guns for fun and the same philosophies apply most of the time like not applying too much grease,etc

Yes, 2mm would be about the smallest with approx. 3mm a more common small screw - 'though the screws are often not metric and thread pitch is all over the place.  Sometimes, one just drills and re-taps the hole to fit a screw one has, or adapts.  For older guns, (mostly they are older if they need fixing,) parts are inconvenient to locate.  As for your friend, a lot of time, the objective is a cleanup, re-finishing the stock, lubrication, re-crowning, bluing and fine tuning the mechanics.  Of course, the pros will do the machining not usually accessible to the hobbyist. 

A target rifle is no fun unless it is mechanically smooth and accurate.  Final accuracy also has lot to do with custom loading the cartridges, which is another obsessive pursuit.

Yeah, both are used to shoot something.   

Indeed, true, Akira!  I felt uncomfortable about mention of this equivalence, when I started to bring my new camera of the time (D200) on visits (gab sessions) at my friend's shop, (professional gunsmith.)  My interest in target shooting and gun repair started to wane with renewed interest in photography.  His perceptive comment was to point out, that from now I was going to be shooting something else.  Indeed, since then I have gone on countless "shoots," but rarely at the rifle range.  There is lots in common.  Both photography and target shooting are highly technical!  Both pursuits lend themselves to endless tinkering!  There is shot discipline.  And, one strives to not harm self and what one shoots.  There's lots of outdoor fresh air; good friends. One could go on...