benrains
12-Apr-2010, 10:47
I picked up an old barrel lens with a mucked up aperture. Most of the blades are in good condition, but it looks like 3-4 need to be replaced and one is missing altogether. I've reassembled apertures before (I learned how to do my first one the hard way when I accidentally dropped all the blades out of lens I was cleaning.) That part is not a big concern to me. What I don't know is what are common ways to fabricate missing or broken blades, and specifically, what are good substitute materials for the blades?
My current thinking is that I can contact print one of the existing good blades onto a sheet of lith film, and then use this as a negative to print replacement blades onto more lith film. These would then be carefully cut out with a sharp razor knife. The brass pins for holding the blades in the aperture ring I think I can make from a suitable gauge of brass rod... with one end filed flat and the other peened slightly to keep them from slipping through the holes in the blades.
My current thinking is that I can contact print one of the existing good blades onto a sheet of lith film, and then use this as a negative to print replacement blades onto more lith film. These would then be carefully cut out with a sharp razor knife. The brass pins for holding the blades in the aperture ring I think I can make from a suitable gauge of brass rod... with one end filed flat and the other peened slightly to keep them from slipping through the holes in the blades.