help! I "fixed" my 40mm Summicron-C but there's a problem

[bellsbells]

Long story short: in trying to remove a filter that was stuck on my beloved Summicron-C 40/2, I managed to get the aperture ring out of alignment. I took the whole thing apart and carefully realigned everything. But when I put it back together, the aperture dot ring is just completely loose and spins around. I have a spanner and made sure to tighten adequately, so that's not the issue. I also made sure the spacer was put back in the right place. I've searched the internets high and low to no avail... what is it that needs to be done to get this ring to stay in place?

On an added note, I noticed that the aperture ring seems to have a longer range now. What I mean is: if I open it all the way, align the dot to the 2, and hold the dot ring in place while I close the aperture all the way, the dot is almost a stop *past* 16. I can't remember it being this way before I "fixed" the lens. It may not be a problem per se, but I wonder if something I did caused this?

Thanks in advance for helping me avoid a trip to the Leica repair shop...

 

[Sid836]

Apparently the ring slips giving the impression of a longer throw. It is an expensive lens and servicing by some expert is recommended.

 

[jaapv]

In your case I would send the lens in to an independent repairperson. In Europe (including the UK for the time being) I would sens it to Wil van manen kameraservice, in the USA to DAG.
Although it is not an expensive lens as Leica lenses go, it is a rather nice lens and well worth saving.

 

[bellsbells]

Thanks, guys, point taken. Service would be the ideal solution, but I cannot afford it at the moment and I really want to be able to use the lens. I'm really not so worried about the extended range, more how to get the dot ring to stay in place! Any suggestions on how to do this would be much appreciated.

 

[DougFord]

Back to the internet batman.
There's all kinds of people 'fixing stuff' and then posting about it on the interwebs.
Here's a link to someone re-assembling a summicron c. Don't know if it helps but it's a start. Good luck.

http://jumboprawn.net/jesse/cams/gear-profiles/leica-summicron-40mm.html

 

[Huss]

Thanks, guys, point taken. Service would be the ideal solution, but I cannot afford it at the moment and I really want to be able to use the lens. I'm really not so worried about the extended range, more how to get the dot ring to stay in place! Any suggestions on how to do this would be much appreciated.

Where are you located? If you happen to be in the Los Angeles area, Walters Camera Repair is very very reasonable. A fraction of the cost of many places. They've done some really good work for me.

 

[rick oleson]

I'm not familiar with that particular lens, but in some cases the diaphragm is not designed to open all the way - it sometimes remains slightly closed at full aperture to serve as a sort of baffle, and the extra opening capacity is actually beyond the max speed of the lens itself. When I do this kind of disassembly I generally use a pin gauge to set the correct opening diameter at the smallest aperture, and let that establish the other stops.

 

[bellsbells]

Back to the internet batman.
There's all kinds of people 'fixing stuff' and then posting about it on the interwebs.
Here's a link to someone re-assembling a summicron c. Don't know if it helps but it's a start. Good luck.

http://jumboprawn.net/jesse/cams/gear-profiles/leica-summicron-40mm.html

Thanks—this is actually the page I referenced to take the lens apart! Sadly it doesn't mention anything specific about how to seat the aperture dot ring.

Where are you located? If you happen to be in the Los Angeles area, Walters Camera Repair is very very reasonable. A fraction of the cost of many places. They've done some really good work for me.

I'm in NYC and I know of several shops here that service Leica lenses. I don't really know what the cost would be, but anything above $50 is out of my range at the moment... and I imagine it would cost more than that. Probably a lot more.

I'm not familiar with that particular lens, but in some cases the diaphragm is not designed to open all the way - it sometimes remains slightly closed at full aperture to serve as a sort of baffle, and the extra opening capacity is actually beyond the max speed of the lens itself. When I do this kind of disassembly I generally use a pin gauge to set the correct opening diameter at the smallest aperture, and let that establish the other stops.

Interesting! I wonder if I stumbled on a secret way to hack the lens to open up extra wide?! If only I could solve this dot ring problem though. Sigh.

 

[bellsbells]

Well whaddya know... I revisited the jumboprawn page and pored over the description again. It says: "Leave the tiny set screw on the front of the lens alone. Removing that will allow the very front of the lens to rotate and unscrew (leaving all glass in place - no harm done). There's generally no benefit to removing this front part of the lens. The f-stop ring stays in place." I had tried removing this screw before just to see what happens, and nothing did—the front of the lens didn't rotate and unscrew as he describes. I tried it again, tightening the screw as much as possible, with the same result. But as I inspected the aperture dot ring I noticed that it seemed more recessed compared to the lens in jumboprawn's photos. Holding it in place, I screwed in the lens cap and pulled outward. I felt ring kind of snap into place, and when I unscrewed the lens cap I found it no longer rotated or moved at all! I can't say yet whether this is a permanent fix, but I handled the aperture ring a bit and took the lens cap on and off a few times, and it hasn't budged. Since I have it mounted on a Minolta CLE which meters off the film, I don't have to worry too much if I'm out shooting and the ring becomes loose again; I can easily guesstimate the f-stop if necessary.

If anyone else on the forum wants to chime with tips or advice on this issue, please do! In the meantime, I hope my DIY fix continues to work and that this info may be useful to any other user with the same problem.

 

[Burnze]

The "aperture ring" that has the dot is glued to the element from the factory. If you put lots of force on it (like overtightening a filter), it will come loose and rotate. This shifts the dot out of place. Sometimes the old glue "locks" it by binding it so it gets stuck in a different spot. Other times it just spins freely.

You have to take it apart and glue it back in place.

 

[bellsbells]

The "aperture ring" that has the dot is glued to the element from the factory. If you put lots of force on it (like overtightening a filter), it will come loose and rotate. This shifts the dot out of place. Sometimes the old glue "locks" it by binding it so it gets stuck in a different spot. Other times it just spins freely.

You have to take it apart and glue it back in place.

Thank you! Even 4 years later my lens is still having this issue, so it's good to know what it is and that it can be repaired. Does anyone have a recommendation for someone in the NYC area to do this repair, or someone in the US by mail?