SMC 50mm Repair
Posted 27/07/2009 - 22:12
Link
Hi
It was the aperture ring sticking at f11, it turned out one of the sprung copper bars that broke and stopped it moving, now fixed.. I think
It was the aperture ring sticking at f11, it turned out one of the sprung copper bars that broke and stopped it moving, now fixed.. I think
Posted 28/07/2009 - 10:36
Link
Thats a usual problem with the SMC-A 50mm F1.7, dunno if its common with other versions (the F1.4 is certainly better built).
The reassembly is not complicated, but can be tricky to keep ball bearing in place, and if you have electric contacts, keep that spring in place as well.
The way I did it was to do it inside my light tent, because the spring did bounce off many times , try to take similar measures.
The ball bearing usually has a bit of grease so it can plugged into place and might hold. If it proves hard to do, use a bit of regular glue, a very tiny amount to keep it in place.
After placing everything in place, put the aperture ring only slightly in, to push the ball bearing in, after this push the opposite side of the ring in. At this point the two metal flaps (or whatever they are) will be stooping the ring form going in, use pencil or similar to push these in while forcing the ring in as well.
If while was done, the spring has not flown off, your home free. Also be aware that the button for the aperture ring might fall off.
I believe setting the aperture ring to the F1.7 position when assembling it was best.
Best of luck.
The reassembly is not complicated, but can be tricky to keep ball bearing in place, and if you have electric contacts, keep that spring in place as well.
The way I did it was to do it inside my light tent, because the spring did bounce off many times , try to take similar measures.
The ball bearing usually has a bit of grease so it can plugged into place and might hold. If it proves hard to do, use a bit of regular glue, a very tiny amount to keep it in place.
After placing everything in place, put the aperture ring only slightly in, to push the ball bearing in, after this push the opposite side of the ring in. At this point the two metal flaps (or whatever they are) will be stooping the ring form going in, use pencil or similar to push these in while forcing the ring in as well.
If while was done, the spring has not flown off, your home free. Also be aware that the button for the aperture ring might fall off.
I believe setting the aperture ring to the F1.7 position when assembling it was best.
Best of luck.
Posted 28/07/2009 - 17:50
Link
Thanks for the response
I believe its a problem with that one model, luckily I pulled it apart in a plastic box so kept all of the bits, but I have no idea where the ball bearing came from and how I can hold the steel spring contact thing in place to do it
Gary
I believe its a problem with that one model, luckily I pulled it apart in a plastic box so kept all of the bits, but I have no idea where the ball bearing came from and how I can hold the steel spring contact thing in place to do it
Gary
Posted 30/07/2009 - 23:23
Link
The ball bearing came from the same place where the spring came from(shown in the last picture on the link you provided).
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10 posts
17 years
I used this website to try and fix my knacked SMC 50mm, http://homepage.mac.com/jpelling/page11/page11.html however,I think I fixed the problem with the aperture jamming, but I cannot for the life of me get it back together, where the ballbearing goes etc etc.
Any help please, the web site was good for taking it apart but sadly lacking in reassembly, I know I should have noticed this whilst reading it but I did'nt
Any help would be greatly appreciated, I have a great lens sitting in a pile of bits
Thanks
Gary