C-Mount Wollensak Raptar 6-inch f/4.5 Disassembly

[Matthew Hall]

I just got this lens for free as several of the aperture blades are mis-aligned. Anybody out there have any experience taking this lens apart? There are numerous set screws and not sure which one does what. The aperture is between the two element groups and this all seems to be located in the front half of the lens. The focusing helical is in the back half so hoping I won't have to mess with that. Thanks.

Edited December 21, 2024 by Matthew Hall
spelling

[Dom Jaeger]

You could try removing the front optics and see if that allows access to the iris, but to get the iris out you will need to remove the pin that connects the aperture ring to the iris cage, and sometimes that is a two stage connection with an inner barrel as an intermediate. Usually a lens needs to be disassembled to remove an iris cage. It may be held in by a lock ring, or a circlip, or set screws, or the front optical group. 

Rebuilding many-bladed irises is tricky if you’ve never done it. You might also find that the loose blades have had their pivot pins ripped out, which makes things much harder.

[Matthew Hall]

Found this online regarding this very lens. Here is the lens completely disassembled, showing all the pieces. Unfortunately there were no instructions as to how to take it apart. I can see the pivot points of the iris through the front element--they are intact. It appears to be the active ring that moves the opposite end of the blades that has the problem. That is hidden from my view under the blades.  I have worked on many apertures before so that should not be a problem. I just wanted to find out if anyone has any information on how this particular lens comes apart. Does everything come out he front or does the lens split in the middle, etc? I just don't want to disassemble any more than is needed.

[Simon Wyss]

Now that you’ve discovered my thread at MF let me copy-paste what stands there:

The two groups on the right I am not able to disassemble, the left one is heavily lacquered and the right one has an inner tube crimp-locked. I should have to bend it back inwards which I dislike.

Perhaps you want to go further than me.