Leica LTM First Leica, first leica problem (stiff aperture ring)

Leica M39 screw mount bodies/lenses
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stuken

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My aperture ring on my Summitar 5cm f2 is really stiff. Not so bad that I can't shoot with it, and it doesn't seem to be the blades sticking. The camera and lens (IIIf/summitar) have been sitting for a while, and my first thought was old grease gumming things up. Any ideas, and could I fix this myself?
 
I sometimes stick a small drop of acetone in there, and it loosens up. I know it's heresy, but you could always try a TINY drop of WD40. Don't get it on the glass, let it go in with a toothpick around the lever.
 
Put some lighter fluid (Ronsonol etc) in a small syringe. Stick the needle between the grooves of the aperture ring. Turn the ring a few times. And that should free it. Worked 100% of the time for me.

BTW, Don't use acetone. It does not do much for sticky lubricants. It may do worse by dissolving old dirt and deposit them elsewhere, only to reharden when the acetone evaporates. Stay clear of WD-40, straight from the can. If you plan to use this, spray some into a jar, and let it settle overnight. You can probably use the oil on top, the bottom parts will be laden with the additives.
 
Acetone may dissolve the Canadian balsam used to cement the glass elements together. IF the front of the lens can be easily unscrewed, CAREFULLY remove the aperture ring and clean out the old grease (with lighter fluid) and relube it.
 
Here's my 'practice' lens :eek:

#1: This is where the lens separates. The previous owner used pliers at this stage. He then gave me the lens. Do not use pliers!! Try wrapping thick rubber bands at the appropriate places, then unscrew in the conventional direction. If it still won't come apart give it to a professional!

#2: If it unscews, set the diaphram either full open or full closed. Then remove these two screws. At this point, do not touch or move the blades (and don't use compressed air to clean anything).

#3: Carefully remove this ring. Clean inside with q-tips and lighter fluid. Without moving or disturbing the main body of the lens, clean the corresponding area on it.

Apply a minimum of new grease (synthetic bicycle bearing grease works well). Do not use too much grease. Reassemble carefully.

DO NOT TRY TO CLEAN THE INNER GLASS SURFACES! They are very easily scratched. If they are hazy, give it to a professional.
 

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Ditto Victor's advice on internal cleaning of Leica lenses. The internal coatings are even more insanely soft than the external ones.

For whatever reason, Leica chose to make the aperture rings on the Summar and Summitar with almost an interference fit. They depend on a proper lube, but the whale oil Leica used then wasn't stable over time.
 
Thanks all, unscrewed everything and cleaned and lubed it and it works great. I was quite pleased with myself.
 
VictorM

Another thank you for your DYI posting #6 in this thread. I was about to send out my Summitar but now I don't have too, problem cured.

Bob
 
Nikon Bob said:
VictorM

Another thank you for your DYI posting #6 in this thread. I was about to send out my Summitar but now I don't have too, problem cured.

Bob
Click to expand...

Glad I could help.
 
Victor M,

You seem to have a bit of knowledge on this lens. I have a pre-war Summitar in good shape but the apperature ring does not line up with the dot correctly. At f12.5 it points to f9. Can I use this procedure to realign?

Thanks in advance,

George
 
The misaligned aperture could be as simple as the front group isn't screwed in all the way. Or, it could be a real pain, and someone put in the internal control ring rotated 180 degrees. (It goes in two ways, but only one is right.) That's more painful to switch, I assure you. Lining up all the pins on the blades is tricky...
 
I don't think it is the front group since when removed the ring with the dot is still on the mount. Someone is in the past has scratched a mark on the dot ring to indicate the correct alignment, so I guess I will just leave it alone and use it like I have for the past 20 years. I tried to remove the two screws on the f-stop ring and adust but that didn't work. I have been trying to find a diagrahm of the lens for a few years but unsuccessfully, I was just hoping you had an easy fix.

Thanks for your time and thoughts,

George
 
My Summitar's aperture marks did not align correctly with the dot. However, since it did go from fully open to fully closed, I simply drew a small line with a fibre tipped pen and used that.
 
That is what has happened to this lens also but they scratched a line on ring with a knife or something so it is a permanent mark.

George
 
I hope someone can answer this question. How do you acces the inner side of the glass near the screw mount? I mean the back element. The front glass in the Summitar unscrews "easily", and that way you can access the back element, but through the blades. Now you can set it fully open and somehow you avoid touching them, but Im afraid a little drop can get into the blades stucking them. (happened to a leaf shutter when tried to clean the back element and needed to disassemble the whole lens)

Basically I want to clean the elements, mainly the back one because it has some fungus.
Will use leitz formula for soft coatings and the softest cloth I can find.

Btw, I found that using many strips of double sided tape around the body is VERY helpful to unscrew front elements. By adding many strips to the body you compensate for the body difference where it collapses from the rest of it. The tape is very grippy and was very helpful to apply a controlled force to unscrew front elements.

edit: I found that when I unscrewed the front elements now when i screw it again it doesnt line with the aperture markings. Maybe Im wrong because didn't wanted to screw with much force because I still need to clean it, but was wondering if its a matter of force applied when screwing it again
 
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Collapse the lens, loosen set-screw holding the bayonet flange, and unscrew the bayonet flange.

If the lens is coated, you don't really want to apply ANY pressure to it. It is insanely easy to wipe off the soft coating. Tomosy calls for a "no pressure" method, where you hold a damp bit of tissue with tweezers or hemostat, and just wipe once across the lens, and then replace that tissue. No pressure other than the weight of the slightly damp tissue.
 
This is a really easy lens to completely strip & clean. If you are having trouble PM me and I can give you some tips
 
So i tried all suggestions and they worked out nicely!!! BUT, how do you guys get rif of dust? OMG, its a headache to get a pristine surface.
The fungus and haze came out nicely and no marks left, coatings are still in there, but dust... grrrr!!!! anyway, i think that with precaution one can clean the lens fully inside out.

One thing to note is that I couldn't take out the cover of the back of the lens (the one with 3 screws) but with the help of a brush I could insert cleaning fluid inside and the focus is butter cream now :)
The aperture is buttery too!! and the aperture mark alignment is pretty close to what it should be, just a lil bit, only just a little off the center of the mark.

I cleaned some haze through the aperture blades and happily none of them came out, phew!

so... how do you get rid of dust? some kind of static brush?
cheers!
 
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