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07-22-2018, 10:00 AM   #1
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SMC-M 28/2.8 aperture blade replacement(s)

I wound up with a nice 28/2.8 with slow aperture blades. Having done it before I got out my tools, tore it all down until I got to the aperture assembly noting along the way that someone had been in this lens before me.

When I got to the aperture I discovered that one of the blades was almost missing one of its tabs that allow it to pivot. It was hanging on by a thread (see attached terrible, out of focus cell phone photo below). Anyone have a source for replacement blades, or know of a lens that uses similar blades that could be modified? I'm not above a bit of careful cutting and crossing my fingers. As it stands this lens is worthless except wide open. I might just leave the blades out and put it back together.

I'm also willing to buy a donor lens if someone has one with a big crack in the glass or something like that.

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07-22-2018, 11:56 AM   #2
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Try a "Wanted" ad in the Market Place. Or keep searching eBay or Goodwill for a donor lens.

Or buy a replacement lens and sell this one for parts. These are not so rare or expensive that it would be difficult to replace.
07-22-2018, 10:09 PM   #3
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... or search for laser micro welding lab somewhere near you. The best way to repair such damages.
07-23-2018, 03:20 AM   #4
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You can look for a very cheap donor or fixer lens.
Otherwise this particular one is probably beyond economical repair.


07-23-2018, 04:44 AM   #5
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I have an M 28mm 2.8 lens with some tiny spots on the rear element.PM'ed you.

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