Justin Low
J for Justin
I've just finished working on my Summitar, and took some pictures along the way. I've written a quick how-to to accompany them, and you may find it here:
http://justinlow.com/articles/repair-leica-summitar
Comments and suggestions are most welcome. Cheers!
http://justinlow.com/articles/repair-leica-summitar
Comments and suggestions are most welcome. Cheers!
N
Nikon Bob
Guest
Thanks for posting this. I was hoping you would describe how to loosen up a very stiff aperture ring which one of mine has. Any suggestions?
Bob
Bob
Justin Low
J for Justin
Hi Bob. I didn't need to access the aperture, so I'm sorry that I can't help you with that part of disassembly.
I'm guessing that it's stiff due to dried lubricants. You can access the front of the blades after removing the front elements. Then you could try gently swabbing the blades with benzene, and follow up with a tiny bit of graphite lube, working it into the aperture blades slowly.
Again, be careful, and beware of lint and stray fibers.
I'm sure another member will chime in here with more details.
I'm guessing that it's stiff due to dried lubricants. You can access the front of the blades after removing the front elements. Then you could try gently swabbing the blades with benzene, and follow up with a tiny bit of graphite lube, working it into the aperture blades slowly.
Again, be careful, and beware of lint and stray fibers.
I'm sure another member will chime in here with more details.
John Shriver
Well-known
The stiffness in the aperture ring isn't the blades. (If it was, they would buckle in an instant!) The ring itself is a very tight fit on the lens barrel, same as with the Summar and collapsible Summicron. There has to be clean light grease in there.
As for internal cleaning, I would recommend ONLY trying this with an uncoated Summitar. The coating on a coated Summitar is very soft on the outside, and more so inside. You need to know the right chemicals to clean the inside, and even then the coating may have to be cleaned off with the haze! (I speak from experience, messing up a Summicron.)
To remove the aperture ring, you would have to remove the inner barrel from the collapsing barrel. Remove the setscrew(s) holding the rear bayonet ring. Pull the optical unit. Then remove the two screws on the aperture ring, remove it, and clean and grease the mating surfaces.
Only if things are really bad do you want to consider removing the iris blades. If that rotating ring is stiff in the lens, you're stuck, but expect to have an "interesting" time putting the blades back.
As for internal cleaning, I would recommend ONLY trying this with an uncoated Summitar. The coating on a coated Summitar is very soft on the outside, and more so inside. You need to know the right chemicals to clean the inside, and even then the coating may have to be cleaned off with the haze! (I speak from experience, messing up a Summicron.)
To remove the aperture ring, you would have to remove the inner barrel from the collapsing barrel. Remove the setscrew(s) holding the rear bayonet ring. Pull the optical unit. Then remove the two screws on the aperture ring, remove it, and clean and grease the mating surfaces.
Only if things are really bad do you want to consider removing the iris blades. If that rotating ring is stiff in the lens, you're stuck, but expect to have an "interesting" time putting the blades back.