Fixed a cheapo zykkor 135mm 2.8 lens, frozen open aperture blades. Took off rear mount and aperture ring, unscrewed rear element which kinda just fell out lol applied naphtha and worked the blades for awhile. application of extra fine graphite to the blades and worked that in as well. Nice and snappy now.
Failed to fix a Tokina 100-300mm lens with slow closing blades. took it apart and cleaned, but it was still slow going back. Looks like then small spring the returns it is worn out, there was a small kink in it. Not a big deal as is closes down fine and opens up all the way when set to its widest aperture manually.