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05-27-2012, 10:03 PM   #1
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8-element Super-Tak 50/1.4 -- aperture ring stiff

I was preparing a Super-Takumar 50/1.4 8-element version for sale, and now I notice the aperture ring is harder to turn that it should be, although the aperture itself works fine. Focusing is smooth. Just too much friction with the aperture ring, same with auto-man in either position. Prescription? If I open it up, anything in particular to look for, or do?

05-28-2012, 12:13 AM   #2
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Assuming the "Auto-aperture" pin still easily operates the blade to open and close fast at all settings...

The common thing is that it might have been slightly dings by something and often the portion that is even with the tripod mount while mounted to the body. I've run across this and it is due to putting down the camera and often resting on the ring a rough landing due to some careless action.

Another is distorting due to compression of the ring and you could test that by squeezing in differing areas while operating. Often if the lens spends time in a busy camera bag that you get this and yes, even if in a case.

Dried out grease is possible if the lens was serviced with a grease that turns tacky with age. I've run across a few that looked at if it was shot up with lithium grease (gray) and not white lithium.

Seldom is metal debris due to contamination of the space between the lens body and the ball bearing and the ring. Dirt and grit from environmental conditions collect inside and unfortunately clog it over time.

Corrosion. Seldom used and stored lenses are actually more prone. They may pick up moisture and are never allowed to dry out. The ball bearing may corrode and cause problems with each use.


After testing and you decide to remove the ring, take care not to allow the ball bearing to escape. This is very easy to have happen while disassembly of a sticky or stuck aperture ring.
05-28-2012, 09:14 AM - 1 Like   #3
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So I'm not sure if your case would be the same as mine but I just recently bought a Sup-Tak 35mm which also had a stiff aperture ring. I remeidied the problem by unscrewing the cover for the focusing distance scale. In my case the last user must have either previously taken it apart or just naturally the ring slid out of position which caused it to be tight.

So I unscrewed the cover and placed equal distance from the top of the cover (and the barrel) and the bottom of the cover (where it meets the aperture ring) making sure there is some distance from each location. After doing this the aperture ring turns smoothly like my other smc and sup tak lenses.

If you require pictures let me know I will try to get for you asap. As I am on a smartphone right now and the mobile site doesn't have uploading abilities.
05-28-2012, 11:22 PM   #4
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Thanks epqwerty, I've never run across that one. Something to look out for.

05-28-2012, 11:47 PM   #5
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Thanks guys, I'll let you know what I discover.
05-30-2012, 11:50 AM   #6
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Yup that method worked for me. I can't say for certain that it was the focus ring plate that was causing the issue but I know after I loosened it and gave it a cleaning it worked. It could very will be that it was dirt that was causing the stiffness. But I did notice that when I reconnected everything the first time and didn't space out the focus ring cover from the aperture ring it was much harder to turn the aperture ring. So it led me to believe that it has some direct cause.
06-08-2012, 01:32 AM   #7
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Yeah, DOF scale was rubbing up against the aperture ring. Unscrewed & adjusted. Now it scrapes a bit against focus ring -- seems impossible to get it right in the middle (it seems perfect until you tighten the screws enough to have them hold it down), but it is acceptable now anyway. No major surgery needed.
06-08-2012, 09:05 PM   #8
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The only hint i cangive you for the spacing is to use very thin shims to adjust it. I used a fine piece of cardboard placed it on both sides. Once everything was screwed on i gently slide the shims out. Easy as pie. I hope that helps you. And good to hear that it was just the focusing ring thingy that was the problem and not major surgery. If you needs pics let me know and ill take some.

06-08-2012, 09:21 PM   #9
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QuoteOriginally posted by epqwerty Quote
The only hint i cangive you for the spacing is to use very thin shims to adjust it. I used a fine piece of cardboard placed it on both sides. Once everything was screwed on i gently slide the shims out. Easy as pie. I hope that helps you. And good to hear that it was just the focusing ring thingy that was the problem and not major surgery. If you needs pics let me know and ill take some.
Yeah, tried that, but it seems to have more to do with the tightening of the screws so it stays in place rather than getting it in just the right place -- I have no trouble until I tighten those screws, which I don't tighten much. It's very minor, I'm not going to worry about it. I did end up opening it up a little bit anyway -- the infinity focus was off...
06-09-2012, 05:39 AM   #10
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Thats odd you shouldnt have had to mess with the infinity focus for that part atleast to my knowledge. I have no other suggestions to give you Unless i take mine apart again and dive deeper which i really dont plan to unless it breaks.
06-09-2012, 08:16 AM   #11
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QuoteOriginally posted by epqwerty Quote
Thats odd you shouldnt have had to mess with the infinity focus for that part atleast to my knowledge. I have no other suggestions to give you Unless i take mine apart again and dive deeper which i really dont plan to unless it breaks.
No, the infinity focus was a separate issue, I'm just rambling. That's an easy fix too.
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