Canon LTM Stiff aperture ring on Canon 50/1.4 ltm

Canon M39 M39 screw mount bodies/lenses

Epimetheus

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I just received a Canon 50/1.4 ltm and it looks good but the aperture ring is very stiff. I once accidentally un-mounted the lens by turning the aperture ring. Is this typical on these and can it be fixed somehow?
 
I guess I need to take the lens apart for this? Do you guys know any links to instructions on how to open the lens or should I just remove the screws and take it from there. There are couple of bigger screws on the back and one very small screw between aperture ring and filter thread. I’m quite handy but I have never taken a lens apart before.
 
Ask and you shall receive!

Click here for my 50/1.4 disassembly pix.

(You shouldn't need to split the front and rear halves of the optical section to clean up your aperture ring, so you can disregard the first pictures. Just remove the optical section from the mount, as shown in the later photos, and it should be accessible.)

A sticky aperture ring actually is a fairly common problem on various Canon lenses of this era. Canon used a lubricant on the aperture ring that didn't age well: over time it turns yellow and gets sticky, more like glue than lubricant! Clean it off with solvent, apply a SMALL amount of a good-quality modern lubricant (I like to use lithium brake-caliper grease from an auto parts store, because it's formulated to stay where you put it) and your aperture ring should feel like new.
 
Sorry to revive such an old thread, but JLW, would your pictures still be available somewhere?

I have a Canon 50/1.4 with the same stiff aperture ring problem. Thanks!
 
I sent to Edward in NYC and it was fixed within 2 days. The cost is very reasonable. Highly recommended.
 
Could you explain a bit more about who/what Edward is, and estimate the cost of a lens CLA, please?


EDWARD SMOLOV
email: 123camerarepair@gmail.com

very famous repairman in east coast. Like someone else states "Eddy can fix pretty much anything" :p
I sent it for relube for about 30$ + shipping.

btw, I asked DAG at the same time. He estimated 80$ + shipping.
 
If you had seen the pictures and description at jlw's site, you wouldn't wonder why it was just 30$. It can be done in half an hour and need no special expertise.
 
Bummer: even the WayBack Machine can't help with copies of those pix - anyone manage to find them anywhere? I have this lens and it's starting to get a bit sticky.
 
EDWARD SMOLOV
email: 123camerarepair@gmail.com

very famous repairman in east coast. Like someone else states "Eddy can fix pretty much anything" :p
I sent it for relube for about 30$ + shipping.

btw, I asked DAG at the same time. He estimated 80$ + shipping.

I'm taking notes! This seems to be great news to people like me. (cheap, inept and clumsy)
 
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Removing the entire optical unit is pretty easy. There is a slotted retaining ring just inside the rangefinder coupling cam. Unscrew that ring and the optical unit should detach without problem.

Next step is to figure out how to dissect the aperture control for relube.
 
If you decide to unscrew either optical cell from the central aperture cell, make a scribe mark to show how tightly it was screwed in. When reassembling, tighten until the scribe mark lines up again. The cell spacing on all lenses is highly critical.
 
Bumping an old thread! I got one of these lenses, heard quite a bit about it. As the norm, my aperture ring is quite stiff, would like to fix it myself. Anyone got any pictorial guide? Thanks!
 
Is there a tiny slotted set screw on the underside (as the lens would rest on the table while mounted) next to the aperture ring? Loosen that and the whole front optical unit should unscrew allowing access to the front of the aperture blades for cleaning. If that isn't enough you'll need to get to the back side as well (likely).
 
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