Voigtlander Barrel issue

[Rick A]

I recently acquired a Voigtlander Dynar 12" lens in barrel. Unfortunately, the diaphragm in the barrel is dropping pins and not functioning as it should. Is it an easy fix (for someone with manual dexterity, not me) or is there a shutter it would be a direct fit in? The glass in in exceptional condition for the age, and everything I've read about it makes me want to keep and use it.
Thank you

[Dan Dozer]

I recently acquired a Voigtlander Dynar 12" lens in barrel. Unfortunately, the diaphragm in the barrel is dropping pins and not functioning as it should. Is it an easy fix (for someone with manual dexterity, not me) or is there a shutter it would be a direct fit in? The glass in in exceptional condition for the age, and everything I've read about it makes me want to keep and use it.
Thank you


I've taken apart lenses with this sort of problem before with success getting them back together (pins in holes). The larger the lens, the easier it is to work with. However, the larger the lens, the more blades you normally have. You have to take it slow and carefully work your way around the iris to make sure all the pins are in place. Don't take all the blades out and try to start from scratch, just try to get the blades that are out of position fixed. It's kind of a delicate process, but can be done. It may hold, but the pins may fall out of the holes again as you use the lens more and more. After all, there is a reason why the pins are not in place right now.

If you have fat, clumsy fingers, it will be more of a challenge. Why not try it and see. The lens doesn't really look very workable as it is right now anyway so what have you got to loose?

[Rick A]

"If you have fat, clumsy fingers, it will be more of a challenge. Why not try it and see. The lens doesn't really look very workable as it is right now anyway so what have you got to loose?"

Yeah, that, my right hand was crushed in an accident and as you can see I've lost the ends of a couple digits. My manual dexterity is not what it once was.

[Tim Deming]

I’ve fixed a few of these. I think the iris blades are tensioned with a threaded ring on theinside of the barrel, alowing you to take apart and retension so it wont fall apart again. A useful method I’ve used for assembly is to coat the blades with light grease or oil, which keeps them stuck together as you assemble. Once it is all assembled, just wash out the oil or grease with hexanes, naptha, lighter fluid, etc. of course, glass elements removed for all of this.

If any pins have fallen out of their blades, they can be epoxied or crimped back in, but this is tricky and the iris will usually be fragile afterward

[Steven Tribe]

My personal experience with older iris leaves is not good. Fixing pins into thin leaves is just about impossible. A more permanent solution is to convert to low technology Waterhouse slots and stops. The next generation will thank you for your foresight because repairs don’t last long.Done this with both a large Suter Petzval and a series IV Cooke.

[Rick A]

Okay, I've managed to get the barrel apart and removed the blades. Now to fab the Waterhouse stops, I plan on using brass shim stock and make them double ended instead of individual inserts. I've done the math, and my son has a friend who can do the machining for me. I hope this works. I'll post photos when finished.