Nikon Fluor Objective Full of Oil!

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Element 56
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Nikon Fluor Objective Full of Oil!

#1 Post by Element 56 » Fri Jun 26, 2020 6:47 pm

Hello,

I have a really nice Nikon Fluor 40x/1.30 Oil, 160/0.17 with an iris diaphragm and unfortunately it is full of oil. I have seen this before on other lenses both oil and non-oil immersion which got me wondering, has there ever been, to the best of anyone's knowledge who cares to reply to this thread, a lens manufactured that the user or manufactured intentionally filled with oil? Seems odd to me that people would do this so I just wonder where they might have gotten the idea. I have heard of oil filled condensers but not objectives. Not sure what the benefit would be but I would think over time oil in the body of a lens like my Nikon would end up damaging it.

Thanks
Kirby

PeteM
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Re: Nikon Fluor Objective Full of Oil!

#2 Post by PeteM » Sat Jun 27, 2020 2:39 am

Don't know what prompted to someone to fill your objective with oil, but I recently received a Nikon CFI 100x Plan objective filled about 1/4 with oil and unusable. It literally poured out after removing the back element. Even after I removed what I could by disassembling the objective and cleaning individual elements, there was apparently some that had seeped between a cemented doublet In my case, I'd guess the motivating factor was idiocy -- maybe "gee the spring nose is sticking lets see if a half cc of oil will fix that?"

MicroBob
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Re: Nikon Fluor Objective Full of Oil!

#3 Post by MicroBob » Sat Jun 27, 2020 5:37 am

Just one little drop more will do no harm! :lol:

apochronaut
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Re: Nikon Fluor Objective Full of Oil!

#4 Post by apochronaut » Sun Jun 28, 2020 3:02 pm

I'm just wondering why you think someone filled it with oil and not that it slowly became fouled over time during use?

MichaelG.
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Re: Nikon Fluor Objective Full of Oil!

#5 Post by MichaelG. » Sun Jun 28, 2020 4:17 pm

apochronaut wrote:
Sun Jun 28, 2020 3:02 pm
I'm just wondering why you think someone filled it with oil ...
.
Possibly learning from this ebay listing :shock:

https://www.ebay.co.uk/itm/Prior-oil-fi ... 2849580222

MichaelG.
Too many 'projects'

apochronaut
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Re: Nikon Fluor Objective Full of Oil!

#6 Post by apochronaut » Sun Jun 28, 2020 6:00 pm

Didn't they try saving production costs by making vitamin E capsules and microscope objectives on the same assembly line just prior to the cessation of microscope production ?

Element 56
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Re: Nikon Fluor Objective Full of Oil!

#7 Post by Element 56 » Mon Jun 29, 2020 6:30 pm

PeteM wrote:
Sat Jun 27, 2020 2:39 am
Don't know what prompted to someone to fill your objective with oil, but I recently received a Nikon CFI 100x Plan objective filled about 1/4 with oil and unusable. It literally poured out after removing the back element. Even after I removed what I could by disassembling the objective and cleaning individual elements, there was apparently some that had seeped between a cemented doublet In my case, I'd guess the motivating factor was idiocy -- maybe "gee the spring nose is sticking lets see if a half cc of oil will fix that?"
Pete, sorry to hear you couldn't bring your lens back to life. I hope you got your money back!
apochronaut wrote:
Sun Jun 28, 2020 3:02 pm
I'm just wondering why you think someone filled it with oil and not that it slowly became fouled over time during use?
apochronaut,

After disassembly I realized there is actually two different types of oil inside. The first I noticed when examining through the back lens and I think it's penetrating oil from the smell and green color. Maybe someone wanted to lub the iris diaphragm! As I proceeded to take the lens apart I found no oil had infiltrated the lowest lens but above that it was saturated and literally pored out from between the other lens assemblies. From that I assumed the lens was filled by simply removing the collar and filling at the iris and because it's really an easy access point. However, I could be wrong and capillary action and a failed seal may be the culprit.

Thanks again for the help and to all who responded!

Kirby

apochronaut
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Re: Nikon Fluor Objective Full of Oil!

#8 Post by apochronaut » Mon Jun 29, 2020 7:07 pm

Old immersion oil that has entered a lens can take on a green colour. I assume that is because it exerts some corrosive action on the brass over long contact with it. It also can make it's way quite high in the objective due to , as you say , capillary action.

I just repaired a 40X dry objective that had a phenomenal amount of oil in it but none on the back of the front lens. There were 4 lens cells in it, separated into two sections by a spacer of about 8mm length. So the back two cells are right up at the top of the objective above the spacer. The objective must have been repeatedly dipped into immersion oil and over time and it worked it's way up between the objective barrel and the objective stack that was spring loaded. Probably the spring action facilitated it.
The first two lens cells are separated by a thin plastic shim, which acted as a sort of gasket, so the oil did not creep into the space between the front and second lens. The seam between the second lens cell and the spacer also was shimmed with a plastic shim but it had been installed poorly , so it was buckled, forming a poor seal. Some oil got in there but the bulk of it entered at the top of the spacer, 2/3 up the lens stack where it invaded the metal to metal seam and entirely coated the front of the third doublet and the interior of the spacer, flowing down into the top of the second cell. Old oil trapped between surfaces had a thick gummy texture and greenish colour when wiped onto a tissue or swab.

Element 56
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Re: Nikon Fluor Objective Full of Oil!

#9 Post by Element 56 » Mon Jun 29, 2020 8:22 pm

apochronaut wrote:
Mon Jun 29, 2020 7:07 pm
Old immersion oil that has entered a lens can take on a green colour. I assume that is because it exerts some corrosive action on the brass over long contact with it. It also can make it's way quite high in the objective due to , as you say , capillary action.

I just repaired a 40X dry objective that had a phenomenal amount of oil in it but none on the back of the front lens. There were 4 lens cells in it, separated into two sections by a spacer of about 8mm length. So the back two cells are right up at the top of the objective above the spacer. The objective must have been repeatedly dipped into immersion oil and over time and it worked it's way up between the objective barrel and the objective stack that was spring loaded. Probably the spring action facilitated it.
The first two lens cells are separated by a thin plastic shim, which acted as a sort of gasket, so the oil did not creep into the space between the front and second lens. The seam between the second lens cell and the spacer also was shimmed with a plastic shim but it had been installed poorly , so it was buckled, forming a poor seal. Some oil got in there but the bulk of it entered at the top of the spacer, 2/3 up the lens stack where it invaded the metal to metal seam and entirely coated the front of the third doublet and the interior of the spacer, flowing down into the top of the second cell. Old oil trapped between surfaces had a thick gummy texture and greenish colour when wiped onto a tissue or swab.
Thank you for sharing this. It jogged my memory!

Your post reminded me of my Zeiss phase contrast oil condenser that is full of green oil. Also I have an older 40x Olympus that the lower lens has a nice even layer of green oil. It still works okay but unless I care to separate the lower doublet it will always be green!

So in the end it's a typical case of someone trying to make something better and by doing so damages a perfectly good lens. It's like the guy on eBay who sands and polishes off the original lacquer finish on antique microscopes and the people who sharpen perfectly good pocket knives with bench grinders! They mean well most of the time! :mrgreen:

Kirby

apochronaut
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Re: Nikon Fluor Objective Full of Oil!

#10 Post by apochronaut » Mon Jun 29, 2020 9:02 pm

I would think that most such cases are due to neglect. Users, not cleaning old oil off prior to applying new, overuse of oil, or in the case of dry objectives, constant accidental dipping of the objective into immersion oil.


It doesn't help to have seal fail, though.

Element 56
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Re: Nikon Fluor Objective Full of Oil!

#11 Post by Element 56 » Thu Jul 02, 2020 11:09 pm

Still a work in progress but I wanted to share this picture of all the pieces inside this Nikon lens and my little assembly fixture. It's actually simple to work on, however, the oil has seeped into every nook and cranny and turned a straight forward job into a difficult one. My solvent of choice in this case is Hexane. I like it for internal lens parts because it evaporates quickly and doesn't leave a film.
Thanks for looking.
Kirby
Assembly.jpg
Assembly.jpg (30.64 KiB) Viewed 4435 times

apochronaut
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Re: Nikon Fluor Objective Full of Oil!

#12 Post by apochronaut » Thu Jul 02, 2020 11:21 pm

very neat set up. I'm a big fan of n-heptane. The tops of markers and pens are very handy .

Element 56
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Re: Nikon Fluor Objective Full of Oil!

#13 Post by Element 56 » Fri Jul 03, 2020 8:35 pm

apochronaut wrote:
Thu Jul 02, 2020 11:21 pm
very neat set up. I'm a big fan of n-heptane. The tops of markers and pens are very handy .
Thanks!

After reading a little about n-heptane I think I'm going to try it when I run out of hexane. Sounds like the better solvent!

You have me intrigued, other than the obvious, what are you using the tops of markers and pens for?

Kirby

PeteM
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Re: Nikon Fluor Objective Full of Oil!

#14 Post by PeteM » Fri Jul 03, 2020 9:10 pm

Clever fixture - thanks for posting.

Curious about your screen name. Barry M.?? or ???

apochronaut
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Re: Nikon Fluor Objective Full of Oil!

#15 Post by apochronaut » Sun Jul 05, 2020 3:05 pm

Element 56 wrote:
Fri Jul 03, 2020 8:35 pm
apochronaut wrote:
Thu Jul 02, 2020 11:21 pm
very neat set up. I'm a big fan of n-heptane. The tops of markers and pens are very handy .
Thanks!

After reading a little about n-heptane I think I'm going to try it when I run out of hexane. Sounds like the better solvent!

You have me intrigued, other than the obvious, what are you using the tops of markers and pens for?

Kirby
I have done quite a few objectives. The pen and marker caps make very useful hollow drift punches, sometimes necessary to drive the lens pack out of the barrel. They will absorb shock if you have to use persuasion and are easily replaceable.

Element 56
Posts: 330
Joined: Thu Oct 13, 2016 3:48 pm
Location: Lancaster County, PA

Re: Nikon Fluor Objective Full of Oil!

#16 Post by Element 56 » Mon Jul 06, 2020 6:25 pm

PeteM wrote:
Fri Jul 03, 2020 9:10 pm
Clever fixture - thanks for posting.
th
Curious about your screen name. Barry M.?? or ???
Thanks, the fixture is a work in progress. It could be improved by adding a sleeve to fit over the stack of lenses to keep them aligned during assembly.

My screen name has no underline line meaning and I have no spacial interest in Barium. I'm not very good at coming up with screen names and in hindsight I should have just used my name. :mrgreen:
apochronaut wrote:
Sun Jul 05, 2020 3:05 pm
I have done quite a few objectives. The pen and marker caps make very useful hollow drift punches, sometimes necessary to drive the lens pack out of the barrel. They will absorb shock if you have to use persuasion and are easily replaceable.
I often use small plastic Nunic and Nalgene specimen containers as drifts for lenses. I have a nice collection of sizes that seem to suit a lot of situation, otherwise I just turn a piece of delrin. However, now that you provided me with another option I will probably run out of pens and markers!

Finished the lens over the weekend! Next I have the 100x that has some sort of familiar looking contamination underside of the lowest lens. I've seen it before on both Olympus and Nikon 40 and 100x lenses. Curious what it might be and why it happens to them.

Once I found a finger print on a lens inside an unnamed objective from the late 1800's! It was in an odd place and I was fairly certain the lens wasn't disassembled before. You can sometimes tell when you're taking one apart if it's been messed with by the way the burrs break off the threads when you unscrew a part. Of course there are other signs from sloppy work! It's interesting what you can find inside of lenses. Usually the normal fungus, mites, corrosion etc... The fingerprint was by far the worst!

Regards,
Kirby

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