Which AO microscope

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MichaelBrock
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Which AO microscope

#1 Post by MichaelBrock » Tue Aug 22, 2017 4:53 pm

I have been reading my way around these forums looking for advice on a first microscope to purchase. I like the idea of purchasing a used microscope that I can upgrade/repair as time & budget suits. The American Optical scopes seem to be a good option for this. They are surprisingly inexpensive on Ebay and seem very well recommended. There also seems to be a great body of resources available for it.

The question then becomes, which model to I look for? Most ebay sellers seem to be rather ignorant of what they have and provide only a few images with no further information. I have read good reviews of the Model 10 and 20, were they of higher quality than the later models like the 110 & 150? Are the later models easier to upgrade (as in have more resources available or more "universal" parts)?

My usage would be "general microscopy". I also homebrew so doing quick checks on yeast vitality would be one purpose. As would studying pond water for interesting things. Maybe take up tardigrade farming...


Thanks for any advice!

Michael
Last edited by MichaelBrock on Sat Aug 26, 2017 1:57 pm, edited 1 time in total.

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Re: Which AO microscope with

#2 Post by zzffnn » Tue Aug 22, 2017 5:19 pm

Welcome to the forum, Michael!

I would recommend 110 or 120 over other models.

110/120 are successors of 10/20 and have wide view field. Their under stage space is more limited though (but that should not be a problem, unless you want to do DIY modification extensively).

50/60/150/160 are lower end student models, which are not easy to upgrade.

410/420 are optically very good (even better than 110/120 when they have their original long 45mm infinity objectives), but tend to have broken focus mechanisms. It may not be easy to repair for a beginner.

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Re: Which AO microscope with

#3 Post by MichaelBrock » Tue Aug 22, 2017 5:37 pm

Thanks for the reply and the welcome! I'll keep an eye out for 110/120s.

I just realized that I really botched the thread title. I can't even imagine what I might have intended it to be!


Michael

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Dale
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Re: Which AO microscope with

#4 Post by Dale » Tue Aug 22, 2017 9:24 pm

I was so lucky to get one of those from a forum member, it spoiled me. There are some awe-
some experts here who can give you priceless help. If you post links to your wanted scopes
they can spot very important flaws. Our classified department is great.
Dale
B&L Stereozoom 4. Nikon E600. AO Biostar 1820.

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Re: Which AO microscope with

#5 Post by MichaelBrock » Wed Aug 23, 2017 12:49 am

I will have another look at the classifieds. When I last did I had no idea what I was looking at :D The problem with ebay is that it seems most sellers have no idea what they have and list any old model number they can find on the microscope (like for an objective). I need to learn to recognize the models for myself.

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Re: Which AO microscope with

#6 Post by KurtM » Wed Aug 23, 2017 1:23 am

AO = good choice! 8-)

I have both Series 10/20 and Series 110/120, and both are fine choices. But best pick one or the other, and stick with it as some components are not interchangeable. The most plentiful component availability on eBay would probably be 10/20, but 110/120 generally means later, more advanced goodies like objectives and condensers.

If you look at Series 10, get to know the different illuminators. The shortcut is go for the 1031 or 1036A lamps. The 1031 is fully self-contained with 20W halogen, and 1036A uses separate transformer, but also centering adjustments which the 1036 lacks. I have found the 1036A almost tailor-made for conversion to LED if that turns you on. Mine is actually battery powered, and thus cordless, and used for a travel scope.

Series 20 and 120 have 100W lamp houses. Is this preferable? For a beginner probably not, but for more advanced probably. Today's digital cameras do much better with limited light, so not quite as big a deal with photomicography. If you go 100W, it might be a bit of a trick to get a deal that actually includes the necessary power supply/transformer.

When compared to the "Big Four" brands, good old AO holds up amazingly well, and when it comes to bang for the buck, there's simply no contest whatever. Today I have two scopes on my bench: a Zeiss WL with DIC, and an AO 120 with POL and dark phase contrast. My travel scope is a Series 10 with POL and bright phase contrast. My primary passion is diatoms.

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Re: Which AO microscope with

#7 Post by wstenberg » Wed Aug 23, 2017 2:26 am

I bought a AO100 in 1987 and used it for 30 years. I just sold it last month. It was still working fine when I sold it. It used infinity optics.
I sold it to a co-worker for $150 and threw in a dark field condenser.
William
Astoria, Oregon

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Re: Which AO microscope with

#8 Post by lorez » Wed Aug 23, 2017 3:19 am

There is certainly a great deal of good, sound advice from folks who actually have experience with that of which they speak in this discussion.

In order of occurrence of problems in design, construction, or serviceability I would rate the Series 10/20 first, the 410/420 second, and the 110/120 third.

There were very few problems with the Series 10 because most of the important parts were brass and stainless steel. The fine focus did develop problems due to wear (usually thirty years), but that is not a defect in my opinion (we all know what an opinion is worth).

The Series 110 had serious problems with the cement in the prism groups of the viewing bodies. This is not a repairable situation so you need to be careful and willing to look for spare parts if the situation arises.

The Series 410 has a fine focus system that is not very well designed and is difficult to repair. Beyond that, I like the 410 (another opinion) and have several.

As I mentioned earlier, I am downsizing and will be happy to visit about your interests in my inventory.

lorez

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Re: Which AO microscope with

#9 Post by Donw » Wed Aug 23, 2017 3:48 am

I use a 10, a 20 and a 'hybrid' scope where the base is from a 20, and the arm/objectives are from a 2 or a 4. I prefer the 20 over the 10, simply because the illumination is much better. Many parts are interchangeable though. I started out with a 10, and moved up to the 20 after a couple of years. Should have done so sooner. If you get a 20, make sure it has the lighting fixture! You don't need to worry so much about the Power Supply, I can show you how to convert it over to 110 or 220, but no fixture, then you've got to be good at tinkering.

One thing I love about AO is: tons of cheap accessories. Yeah, they may not be as 'good' as some of the big names, but if you're the kind of person who loves to experiment, then AO is the answer.

My personal recommendation is that you get yourself a 20X .50 Plan Achro objective (Cat # 1022 or 1022S) for observing protozoa. I spend most of my time between the 10X and 20X when observing critters like this, and the 20X is nice, with a high NA. I won't say that it is as good as a fluorite... but it ain't very far away!

I often buy AO equipment and rebuild successfully. If you want some tips for buying used, or repairing, just email.

Do you know about https://user.xmission.com/~psneeley/Per ... oscope.htm ? Great resource.

Don

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Re: Which AO microscope with

#10 Post by Dale » Wed Aug 23, 2017 5:15 am

Michael, I can personally attest to the caliber of Lorez' fine 'inventory', and
his expertise extends to very fine imbibements.
Dale
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Re: Which AO microscope with

#11 Post by apochronaut » Wed Aug 23, 2017 12:35 pm

While it is true that the 400 series can have some fine focus problems on occasion, I don't think the problem is as extreme as one reads about it. Many people reporting this, have never actually used one.I have had around 10 of them in my hands and only one, had an easily repairable problem. Every microscope will suffer from problems with the focus mechanisms over time. Keeping a microscope that gets use in shape is one of the duties of a microscopist.

Where the 400 series shines over the previous two professional series, the 10/20 and 110/120, is in refinements in it's user friendliness such as a partially rotateable stage, quick condenser height adjustment, stable electronics, a wide field aspheric condenser and in general better overall optics. The D.I.N. optics made for the 400 series are not just good, they are fine. The planachros have better contrast and there is an option to use planfluorite and planapos too. There are a few planapos for the earlier series' ( 10x and 40x only) and while very good, they are hard to find and necessarily expensive. I have used every optic made for all of those three series of microscopes.

The nice thing is that they have this absurd fragile reputation, so they often sell for peanuts on the second hand market
Last edited by apochronaut on Wed Aug 23, 2017 10:13 pm, edited 1 time in total.

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Re: Which AO microscope with

#12 Post by photomicro » Wed Aug 23, 2017 12:45 pm

As an owner, and lover, of a Series 10, I am getting a lot out of this thread. This is partly because I am in the UK, and they seem like Hen's teeth over here.

The fine focus is a dream, the mechanical stage simple but very effective, and the wide view of the infinity optics excellent. I just wish I could get a phase condenser for it, and reiterate the compatibility issues stated earlier. For some reason at some stage the swapped the 'pin' and 'notch' round!

Ebay has gear listed, but the automatic system of making postage and import charges huge is off putting for us this side of the pond.

I agree, the standard achro x20 is a great lens.

Mike

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Re: Which AO microscope with

#13 Post by MichaelBrock » Wed Aug 23, 2017 1:58 pm

Thank you very much for all of the replies! I have I participate in quite a few "hobby" related forums and this is near the top in quality and quantity.

It sounds like each of the 10/20, 110/120, and 410/420 scopes have their issues and advantages. Every response I read I seemed to have switched allegiances. 110!? that's the one...or maybe 10, hmm, the 410 sounds like the one! I think the message there is that I will likely be happy with any of them.
Donw wrote:My personal recommendation is that you get yourself a 20X .50 Plan Achro objective (Cat # 1022 or 1022S) for observing protozoa. I spend most of my time between the 10X and 20X when observing critters like this, and the 20X is nice, with a high NA. I won't say that it is as good as a fluorite... but it ain't very far away!

I often buy AO equipment and rebuild successfully. If you want some tips for buying used, or repairing, just email.

Do you know about https://user.xmission.com/~psneeley/Per ... oscope.htm ? Great resource.
I will add the 20x to my "probably should get one of those" list. I did find the xmission.com site. It definitely looks like a great resource and is what convinced me that there was sufficient support for the AO scopes to be a great option. The one thing it seems to lack, or at least I couldn't find, is a comprehensive list of what features each of the models had. I think figuring that out, and learning how they vary in appearance, is going to be the key to figuring out what is being offered on Ebay. For example, I have no idea what model this is:

http://www.ebay.com/itm/American-Optica ... Sw1xhZl0Ju

Thanks again for all of the information. I'll work my way through them again (and probably again). It always amazes me how the information to be gleaned from something develops as you learn more.

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Re: Which AO microscope with

#14 Post by Dale » Wed Aug 23, 2017 2:25 pm

Don't give up on the xmission site, it can take some digging to find what you want. AO
produced great repair, use, and detailed model features.
Dale
B&L Stereozoom 4. Nikon E600. AO Biostar 1820.

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Re: Which AO microscope with

#15 Post by Charles » Wed Aug 23, 2017 2:43 pm

That model is the 20.

There are more options available, on places like ebay, in the 10/20/110/120 models. A lot of the items on these stands are also interchangeable.

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Re: Which AO microscope with

#16 Post by apochronaut » Wed Aug 23, 2017 11:27 pm

[/quote]
http://www.ebay.com/itm/American-Optica ... Sw1xhZl0Ju
viewtopic.php?f=5&t=5073&p=46234&hilit= ... ist#p46234
Thanks again for all of the information. I'll work my way through them again (and probably again). It always amazes me how the information to be gleaned from something develops as you learn more.[/quote]

To add to what Charles said. That is a series 20 with a trinocular tube. and at it's current asking price, it is a steal, especially with the uncommon 5 position nosepiece.

The way to look at the professional AO infinity corrected microscopes, made for about 40 years between the early 60's and the early 2000's is in 3 series, each with two branches of differing illumination and filtering capabilities . The series 10/20, was made from the early 60's until about 1980, the series 110/120 was made between about 1980 and 1986 and the series 410/420 was made between 1986 and the early 2000's.
There were 4 owners of the company, during the entire infinity corrected production era: American Optical Company, Warner Lambert, Cambridge Instruments and Leica Microsystems. The series 10/20 are only marked AO, the 110/120 can be marked AO, Cambridge or Reichert, the series 410/420 can be marked Cambridge,Reichert or Leica.
The 10/20 has a limitation of a 19mm f.o.v., the 110/120 is 20mm f.o.v. and the 410/420 is 20mm f.o.v. Both of the 110/120 and the 410/420 can be made to have a wider f.o.v., up to around 24mm, if one can find suitable well corrected eyepieces.

The objectives made for the 10/20 and 110/120 are cross compatible. Here is a very complete list, not including the 9 phase contrast objectives.
viewtopic.php?f=5&t=5073&p=46234&hilit= ... ist#p46234
There were several planachros and planapos developed in the 1980's for the series 110/120 that can be used to improve the colour correction and contrast of the earlier 10/20 series. The 45mm D.I.N. objectives made for the series 410/420 are improvements over the previous 34mm parfocal objectives, with a few exceptions. The 34mm parfocal objectives can be used on the series 410/420 either with or without 11mm extensions but a series 110/120 head needs to be used for proper correction. Similarly, the 45mm parfocal objectives can be used on the two earlier series, as long as a series 400 seidentopf head is installed as well, in order for proper correction. So, in other words the 34mm and 45mm parfocal objectives cannot be mixed.

Each series has a common microscope stand, affixed above an illuminator body. In each series, the "10" version is the basic in base illuminator version: Eighteen watt tungsten or later 20 watt halogen for the series 10, twenty watt halogen for the series 110 and 24 watt halogen for the series 410.
The "20" versions all have a 100 watt halogen illuminator attached remotely at the back of the illuminator base and a filter carousel with between 10 and 15 filters in either 2 or 3 overlapping discs, depending on the series. They all use the same 100 watt bulb.
The "10" and "20" versions in each series are identical above the illuminator body.

For fluorescence, dark field and DIC use, the 100 watt version is desirable and necessary. For other basic uses, bright field and phase the standard in base wattage is adequate. If one thinks at all, that they might gravitate to 100x DF in the future, it is worthwhile to wait for an attractively priced example of any of the "20" microscopes to come along. 45mm parfocal 100x objectives with an iris diaphragm are much less common than the 34mm parfocal version but the iris equipped 45mm parfocal objectives made for Austrian Reichert microscopes are compatible and easier to find. Early Leica infinity D.I.N. optics will work, as well as some infinity Chinese optics and Olympus too, with a small magnification error.
While the 100 watt microscopes have excessive brightness for normal use and a larger footprint, they can be attenuated with the transformer and the built in filtering and in general are a more complete and versatile system.

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Re: Which AO microscope with

#17 Post by MichaelBrock » Thu Aug 24, 2017 12:35 am

apochronaut, thank you for a very informative post! I think I'm starting to get a better feel for the various AO models & options. I'm going to keep my eye on that model 20.

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Re: Which AO microscope with

#18 Post by apochronaut » Thu Aug 24, 2017 12:41 pm

Glad to be of help. Hope it all works out for you. P.M. me if you have further questions. I sometimes will know the answer.

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Re: Which AO microscope

#19 Post by MichaelBrock » Sat Aug 26, 2017 2:01 pm

I ended up winning that AO 20 mentioned above I'm psyched! I have read through the manuals a few times already but there is only so much you can glean without seeing the actual microscope.

The microscope is a trinocular and appears to have some sort of adapter in it. I see that there are official AO dust caps for these heads. Does anyone happen to have one for sale?

Also, the Aperture Viewing Unit #1245. Luxury or necessity for the phase microscope?

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Re: Which AO microscope

#20 Post by Charles » Sat Aug 26, 2017 6:34 pm

The adapter is for the AO 35mm camera shutter, which you can see here:
http://www.ebay.com/itm/American-Optica ... SwEeVZedNG.
You will need to replace it with a photo tube which looks like this one:
http://www.ebay.com/itm/American-Optica ... SwbIRZedMD. Here is one for purchase by itself:
http://www.ebay.com/itm/PARFOCAL-TUBE-F ... xy63FS5wCR

The caps are hard to come by. You can use plastic water bottle/soda bottle caps.

The viewing unit you are referring to is probably the unit which you can also see between the head and objective turret in the second link above. It is used to align the phase annuli in the condenser with the phase ring in the objective. It is not necessary but makes aligning easier. You can also get a phase telescope which will do the same thing.

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Re: Which AO microscope

#21 Post by Dale » Sat Aug 26, 2017 7:18 pm

I just happen to have one of those phototubes, that I don't want. I would have to dig
through many boxes of unpacked lab equipment, so I'll wait for your assessment of
your photo needs.
Dale
B&L Stereozoom 4. Nikon E600. AO Biostar 1820.

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Re: Which AO microscope

#22 Post by MichaelBrock » Mon Aug 28, 2017 7:07 pm

Thanks for the reply Charles, that helped. So the adapter on the scope I bought is specific to the AO camera shutter Not of much use to me!
Dale wrote:I just happen to have one of those phototubes, that I don't want. I would have to dig
through many boxes of unpacked lab equipment, so I'll wait for your assessment of
your photo needs.
Dale
I currently lack a DSLR, so my plan is probably going to start as frugal as I can get. Probably with a cheap Aliexpress USB camera. I don't think I would ever really go after the "high quality photograph" end of things. I see myself using it more for capturing "finds", like that first tardigrade, or if I ever find the patience and skill to arrange diatoms on a slide.


Mike

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Re: Which AO microscope

#23 Post by apochronaut » Mon Aug 28, 2017 11:22 pm

That little short tube could be built on, to get to an adapter for a digital camera. You need a # 1054 eyepiece in the tube, with any reticle installed removed.
A lot of other lenses I have tried, have peripheral aberrations; mostly some coma or lateral c a. Enough to be annoying.

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Re: Which AO microscope

#24 Post by MichaelBrock » Thu Aug 31, 2017 12:19 am

The AO 20 has arrived! And of course with it come the questions.

The microscope came with all 8 filters and I cleaned those up and put them in place. However, in the bag that held the filters there was one mystery disk. It is the same diameter as the filters but appears opaque (a very bright LED flash light resulted in no light transmitted). It is a matte black/dark grey and feels like maybe "poker chip" material. I have attached a picture. Any ideas?

Oddly, all of the knurled screws are rusted but everything else is in good shape with the exception that the front/back adjustment of the stage is completely frozen. It looks easy enough to break down, clean, and lubricate. The documentation available a xmission lacks anything covering the stages as far as I can tell though. Does documentation showing the break down of the stages exist?

One question about the filter wheels. The top wheel rotates freely. the bottom wheel feels as though it is screwing in/out as you rotate it (screws downward as you turn it horizontal; typical "righty tighty"). Is this normal? The break down illustration in the documentation shows that both wheels share the same design for their "axle" so I think there must be something amiss there.

Thanks again for all of the advice,

Michael
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Re: Which AO microscope

#25 Post by apochronaut » Thu Aug 31, 2017 1:42 am

Those knurled screws are plated straight on to steel, which is a poor fusion. Such plating is pretty subject to the corrosion by the small amount of salts evident on human fingers. Immerse them in some carbonated drink overnight. The rust will dissolve away and they will brighten up quite a bit with a toothbrush and a bit of toothpaste.

The opaque disc, I have used to create a kind of oblique illumination by partially rotating it in or out. By passing one over the other in the filter wheel, you can vary the area of illumination some for off set illumination or oblique. If it had been thicker, I might have thought it is a short wavelength filter for fluorescence but I think it is a light block. Some short wavelength filters pass limited visible light.

The filter wheels on that microscope were multi purpose but mainly for transmitted fluorescence, something that is not used as much as epi fluorescence these days. Some of your filters are probably dedicated fluorescence filters. They should be marked.

That filter wheel is probably stuck to the mounting screw with hardened grease and is turning the screw in and out as you turn it. I always try a little very light machine oil, shaver oil or the like to free up hardened grease but there is nothing wrong with spending the time to break things down and clean and re-lubricate everything. However, you need the correct lubricants and in lieu of having the correct ones, re-emulsifying the old ones with a light oil , is sometimes a better option. The stage will need proper damping grease, which acts as both as a clutch and a lubricant. Nye makes a good one and the Corning silicone grease is good too.

I might have some info on that stage. They are pretty simple though. Often the grease in the control shafts is the problem.

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Re: Which AO microscope

#26 Post by MichaelBrock » Thu Aug 31, 2017 2:18 am

As always a thoroughly useful and informative reply apochronaut. You should write a book, seriously. I don't know how many AO enthusiasts there are, but I would buy it!

I will keep the opaque disk handy in case I should need some "oblique illumination" down the road. And I'll put those knurled screws in some soda water post haste. And of course your description of what is going on with the filter wheel makes perfect sense. Fits what I'm seeing.

I was planning on using lithium grease but would plastilube (recommended on the xmissions site) do the trick?


And, while I have your attention :D Initially I thought the transformer was having issues...but it turns out I was expecting 12v DC out, rather than AC. Once I got that figured out it suddenly started working! So power is available at the connector on the back of the power supply but doesn't make it to the connectors where the bulb is attached. I'd like to open the lamp holder to check the interior wiring but I'm afraid to force the strain relief on the wire going in. Do you know if that strain relief can be removed or if it is of the "permanent" variety?

Edited to add: I ended up disconnecting the socket end of the lamp holder and was able to take it apart. Power is getting to the leads going in to the socket itself. So progress.

Mike

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Re: Which AO microscope

#27 Post by apochronaut » Thu Aug 31, 2017 2:50 pm

Does it have that tweezer type of lamp socket? Most are but there is a push in type too, with a mica insulator around it. Sometimes the tweezer contact bars inside can get a bit oxidized over time. A little mis-contact and then a little heat and ozidation, and then more mis-contact and more heat. You probably know the scenario, actual burning and melting can take place . You can go in with a small round or 1/2 round file and clean them up. Have you metered the bulb to check for continuity? i came across one once where the actual input pin of the bulb was severed, just inside the molded glass but the filament was intact.

I don't know plastilube, very well. I guess if it has been used by people recommending it on P.S. Neeley's site , then it should be o.k. Lithium grease and any grease formulated for most conventional applications, such as chassis lubrication etc. are too thin.
The ones, I am currently using are Nye 362 HB( quite expensive) and Dow Corning 1 11, which is a silicone grease.

There are many damping greases that will work and the viscosity required does depend on the mechanism being greased too. For the ball track on the stage, you could go a little thinner because the clutching action takes place mostly in the coaxial control mechanism and that is where lubricant caking often takes place too.
You have to at first analyze, where the problem is. Sometimes, just a little light machine oil introduced at a critical point, getting the evaporated solvents back into the grease, can do wonders and save a lot of time.

Somewhere there is a list of recommended greases AO used. There were 11 or something like that, so the viscosity and lubricating qualities were quite specific.

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Re: Which AO microscope

#28 Post by MichaelBrock » Thu Aug 31, 2017 3:26 pm

It does have the tweezer type of socket. It all looks to be in great shape and I think the issue is almost certainly just oxidation preventing a good contact. I have the screws & washers soaking in a mild acid and plan on cleaning the contacts in the socket next. The bulb seems fine but I didn't test it. I did proactively buy a new bulb though and that bulb also fails to light.

I didn't manage to find a blow-up diagram of the stage but did manage to carefully disassemble the stage mechanism until I got down to only the housing holding the gear which racks the stage forward/back and the shaft it sits on. I have attached an image below. The central shaft there is free turning (the gear on that shaft is responsible for moving the slide holder left/right) and I slid that out. I currently have a light oil on it in an attempt to loosen things up. The gear and the metal shaft with the dimple (which is for the set screw for the knob which turns it) seem to be contiguous. My theory is that the brass threaded end and the cap on the left side are also a single piece and I may be able to tap that shaft towards the left.

I'll go looking for the list of lubricants. I can't see spending a major % of what I spent on the microscope on lubricants but you never know. I'm also not particularly patient when I have a task in front of me...so hopefully whatever best suits isn't going to require me to order it from overseas. :)
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apochronaut
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Re: Which AO microscope

#29 Post by apochronaut » Thu Aug 31, 2017 6:05 pm

Be careful tapping. the tiniest bit of out of true and it will be trouble. I'm a big fan of using the POP method. Use it wisely and everything just pops apart.
Stands for Penetrating OIl and Patience.


Three lubricants I remember are Shell # 3, Mobil Plastilube and Graphite powder is added to them. The others, if I recall were proprietary oils or greases from mostly local suppliers in Western N.Y. State. There was and still is a substantial optics industry there, so no doubt some suppliers developed over the years, that had expertise in lubricant formulations for optics and precision machinery.

I will keep looking.

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Re: Which AO microscope

#30 Post by MichaelBrock » Thu Aug 31, 2017 11:28 pm

In the end a little heat from a heat gun loosened things up well enough to get it apart.

I cleaned up the wire connectors and screws and rebuilt the scissor socket but still not getting power flowing to the bulb. I need to figure out something small enough to get down inside of the socket to clean off those contacts.
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