|Posted: Wed Nov 28, 2018 6:40 pm Post subject: Vivitar (komine) 400mm f5.6 disassembly
|I am cleaning this lens - fungus. Front end was easy. I am trying to figure out how to get at the rear group. This lens block focusses ie whole optical assembly moves. The rear group is in too deep to access from the mount end. It is clear I need to separate the lens at the helicoid. I am not sure if this is a double helicoid or just a set up with sliding rails that prevents the front end rotating.
I thought at first it might be like a soligor, that the focus sleeve would slide up out of the way once the 3 grub screws (one is arrowed in pic) under the rubber grip had been loosened. Not the case: the focus rotates freely but doesn't move up or down.
Not sure what to do next. I am wondering if I should rotate the focus to cfd, then loosen the grub screws, move the sleeve all the way back round to the infinity stop, retighten the grub screws and rotate again to the cfd stop...
Update. I found this thread:
So Actually I could separate the lens at the tripod mount. But then this guy couldn't reassemble!
pentax ME super (retired)
Pentax K5; Samsung NX 20; Lumix G1;
Adaptall collection (proliferating!) inc 200-500mm 31A.
Primes inc takumar 55mm; smc 28mm, 50mm; sigma superwide II; helios 58mm, Tamron Nestar 400mm, novoflex 400mm, Vivitar 135mm close focus, 90mm macro; Jupiter 11A; CZJ 135mm.
A classic zoom or two: VS1 (komine), Kiron Zoomlock...