Zeiss Photomicroscope III condenser carrier spring-pin stuck

[iPeace]

HI all,
I have a Zeiss PM III, which appears to have a PM II condenser carrier, ie. the centering screws point diagonally to the rear, and there is a spring-loaded pin in the front. That pin assembly is a knurled cap screw with an axial hole facing the user, through which, I assume, the pin slides, which it doesn't. If a condenser is in the carrier, the spring pin cap screw cannot engage the threads on the carrier. There is a very small (~1 mm) screw through the side of the cap screw, near the operator end. I assume this keeps the pin in the cap screw. I have tried backing that out a bit, and pressing the cap screw while the end of the pin is against a hardwood block. Does not budge.

My next step will be an aluminum block for the pointy end, and a plastic tube on the cap screw end, and a small hammer. I thought I would ask here for better ideas, since I doubt I can call Zeiss and get a new one if this goes bad.

TIA,
Scott

[woyjwjl]

Heat can solve all problems, but it may also solve the problem itself. Good luck.

[FredH]

My experience with several of these spring pin assemblies from Zeiss Standard condenser carriers is that several hours of soaking in solvent (Ronsonol lighter fluid) or penetrating oil (Kroil) fails to free them up, but then a few minutes of heating with a hot-air heat gun, plus moderate pressure on the pin, renders the pin free to move. No need for hammering or applying great force.