MicrobeHunter.com Microscopy Forum

Do any of you have experience disassembling a Carl Zeiss Jena Amplival phase contrast condenser (phasenkontrast kondensor) Phv Apl 0,9/e? If so, I'd appreciate getting some disassembly tips. The knurled edge/ring is very stuff which says that the grease has set up quite hard. I'm looking at disassembly, cleaning, and lubrication.

Note that the condenser rotates to supply the matching appropriate ring for each objective as well as a blank space with an iris diaphragm for brightfield use.

See photos appended.

Thanks!

I need to unscrew the brass ring in the condenser assembly. However, finding the appropriate tool for this job is a bit of a challenge. I have various names for this tool, none of which may be accurate. They include "snake-eye spanner," "notched spanner," "drilled spanner," and "retaining ring removal tool." Does anyone have an accurate name for this tool? The distance hole to hole is 10 mm. Also, if you are familiar with this tool, where can it be acquired?

They are also known as Pin Spanner or Pin Wrench

I believe it's called a "pin wrench" or "spanner". If you search for either term you will find some hits here including:

viewtopic.php?f=18&t=6030&hilit=pin+wrench

and a recent one that I bookmarked:

viewtopic.php?f=5&t=6458&p=57793&hilit=wrench#p57793

Camera buffs call the Spanner Wrenches

Here is a set that might work for you, just make sure it closes enough for what you need it for.

https://www.amazon.com/dp/B00QRPWCN0/re ... B00NURCWTC

Thanks for your help. Much appreciated!

Hi Peter,
I would first remove the top lens of the condenser so it won't be scratched. It might be stuck due to old hardened immersion oil residues.
The only big problem with Zeiss Jena gear is that the greases harden up more than those in other brands microscopes.
They can be softened to some degree by warming them up a little. As long as there are cemented lenses or the phase rings in th way I wouldn't go beyond 60 °C. The phase discs are easy to damage so be careful with them. Apart from that it shouldn't be a problem to dismantle the thing. Use appropriate screwdrivers for each slot. Instrument screws often have comparatively narrow slots. Don't use a smaller screw driver then but grind the thickness of the blade down, while keeping the blade below 230°C (it shouldn't start to take colour).

For mircoscopes you often need special tools. If you cant get access with a standard pin wrench this would be the case.

Bob

Thanks for that advice Bob. The black top lens of the condenser comes off no problem. However, there's another lens underneath that, which is seated on a silver ring (see appended photos). It seems to me that this ring should also unscrew, but it's exceptionally tight. Do you think this silver ring is removal? If so, it will probably require the heat treatment that you recommend. That lens must also lift out somehow. Very tricky!

Peter

Look closely all around for set screws. Maybe the silver collar can stay in place after you have loosened the brass screw in the middle. It doesn't have anything to do with the turning of the ring with the stops.

There is a tiny set screw in the black base of the silver lens ring which I removed. Evidence that the ring twists off/unscrews. I ordered a pin spanner and will remove the brass ring ASAP. We'll see what happens after that.

If I can't find a solution, I'll take it to one of the microscope technicians at my provincial university (Memorial University). I just started to build a relationship with him, and he appears happy to provide advice re. rehabilitating the "old" Jena Amplival microscope.

By the way, the technician I spoke with yesterday told me that he and his colleague had attended a microscope workshop in Pennsylvania, USA, given by Mark Moore. This must be him - https://www.microscopyusa.com/instructor

See also this - https://docs.wixstatic.com/ugd/baea13_c ... 1a59b8.pdf

Some advice was provided at the workshop that is different from some of that offered on this and other fora. E.g., optical components such as objectives are cleaned primarily with 70% isopropyl alcohol and Q-tips cotton swabs (that brand only).

PeterArmitage wrote: Some advice was provided at the workshop that is different from that some of that offered on this and other fora. E.g., optical components such as objectives are cleaned primarily with 70% isopropyl alcohol and Q-tips cotton swabs (that brand only).

That is in line with the Zeiss in house cleaning solution. It is a mix of isopropyl alcohol and hexane. I personally start with just distilled water. I talked to the owner of a store in New York about it once. He said that people use a wide variety and have their preference. I don't think it matters that much if you stay away for specific chemicals.

mnmyco

Gerd, on the German Mikro-Forum tells me this is not an Amplival microscope. It's an Ergaval. He provided relevant documentation. Thanks Gerd!