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Mike Tobias
22-Nov-2008, 22:24
So I searched the forum to see if anyone had previously discussed this and came up with nothing so here we go. I received an old brass lens in shutter (no name on lens, came off an old Lancaster camera) from eBay. Glass is fine, shutter fires fine, but it looked like the aperture blades had come loose in their mount. No big deal, I've put aperture blades back before, just takes a bit of time. After I open it up, I find 10 spaces.....and only 9 blades. Sigh.

So here's my question. Is there a good way to make replacement blades? I've got a couple of ideas but figured I'd ask and see if anyone has done this before to see if someone has some pointers. Also, is there maybe some one who might have a single replacement blade they might want to sell me? Hey, it's worth a try. Here's a photo of one of the blades I've currently got, perhaps that will help. Thanks to anyone who has some advice!

Mike

BarryS
22-Nov-2008, 22:37
Finding a correct sized replacement blade isn't going to be easy. I've rebuilt a number of old irises and I also have a lens that was missing one blade. Funny thing--it's a Lancaster Rectigraph. Even without the blade, the aperture is still reasonably round, but I've got 17 of 18 blades. With 9 of 10 blades, your aperture is going to be more irregular, but it probably isn't going to make a big difference in your images.

lenser
22-Nov-2008, 23:27
Mike,

I don't know if it will work in your case with this lens, but I sent a tiny brass extreme wide angle for a whole plate camera to Carol at Flutot's with all the blades in a film can. Turns out one was missing, but she got it reassembled properly without the missing blade and you simply cannot tell that it is gone. Maybe you will have the same luck on yours. Mine requires 17 blades but with just sixteen it functions perfectly with no gaps or binding.

If that doesn't work, I suggest contacting Carol as I know she has a large stock of old shutters and diaphragms for parts. Maybe she will have what you need.

Good luck!

Tim

Mike Tobias
23-Nov-2008, 18:00
Thanks for the advice. Actually, I'm not terribly concerned with the shape of the aperture (you're right, 9 blades vs 10 is negligible), but I was more interested in the integrity of the aperture. I was under the impression that the blades only stayed in place if you had all of them, and that the iris might jam if not all the blades were in place. Perhaps this isn't true? If that's indeed the case I'll just re-assemble the lens as it is.

Mike

Don Dudenbostel
23-Nov-2008, 18:38
I have a related problem with my (I think 14.5 in Veritar). I have all of the blades but the pivot pin on on end of one blade is missing. Can that pin be fabricated and replaced?

Glenn Thoreson
24-Nov-2008, 12:25
I needed to fabricate shutter blade a while back. It was terribly fussy work, but with patience, it now operates perfectly. I don't think you would have a terribly hard time making a new blade if you did as I did. For example, the end with the operating pin/eye is going to be the hard part. If you can find an old blade that's damaged or the wrong size/shape that has that tiny part, you can very carefully remove the needed part for attachment to your new blade. The blade material itself shouldn't be too hard to come up with. For an iris, though, I think if it will operate reliably without it, that's how I would use it. Good luck. :D

David E. Rose
24-Nov-2008, 15:38
S.K. Grimes can probably provide a replacement for you. They provided a set of shutter blabes for a Kodak 250mm Wide Field Ektar for me. The old blades have a tendency to deteriorate around the pivot holes, causing the blades to get sloppy and eventually hang up and jamb the shutter. The replacement blades were plastic duplicates of the originals and were reasonable in price.