Argus c3 Aperture adjustment
I just picked up an Argus C3, so far, I'm really impressed, but I've been forced to shoot with the aperture wide open as it seems to be stuck there. I'm not sure whether the aperture adjustment ring is stuck, or if I am trying to turn the wrong part/doing something else wrong. I am afraid to try and force it. I looked at the manual online, but there is no illustration on how to actually adjust the f-stop, just an explanation of what the aperture does.
Just guessing, it seems the ring that actually has the stops printed on it is what should be rotating, but it won't budge.
So can anyone out there tell me how (in detail) to adjust the aperture, or what may be gummed up and steps to fix the problem?
Yes, the printed ring should rotate -- mine also has two little round studs sticking up to help get a grip on it.
There is some C3 info at the Argus Collectors' Group site, but in a quick look I didn't see anything about the lens internals. I've had my lens apart far enough to clean and relube the focusing helix, but so far the aperture just works. The lens comes off the body by removing the idler gear between the lens and rangefinder wheel, then unscrewing the lens barrel. There is a screw in the side of the barrel that keys into a slot in one of the internal parts. The helix has about six or so parallel threads; it's possible to fit it back about six different ways, only one of which is correct, so be sure to mark some stuff before digging too deeply, should you deside to get out the screwdrivers.
So it appears that my aperture ring is stuck. Any and all attempts to rotate it result in deep frustration and sore fingers. I wonder now if there is a problem with the ring itself or the actual blades of the diaphragm. I read (I think here on apug) that someone used wd-40 to free the ring up, but I want to make sure that this won't hurt things if I try it. The person who wrote whatever post I read said he used a needle to deliver some wd-40 around the ring to get it moving again, but I am afraid this might do some harm to the lens. Even if it doesn't harm the lens it may not fix my problem. That is to say that the ring may be immovable because the aperture itself is gummed up and unable to move.
Is there anyone who has had similar immovable aperture ring problems? I'd be interested to hear the solutions you folks used when confronted with such issues.
As a side note Dave, what type of lubricant did you use on the focusing helix? I have actually disassembled the lens as far as you and managed to smooth out the focusing to a usable degree by just cleaning the threads of the cosmoline-like grease that they were caked with, but was wondering what would be a suitable replacement for said lubricant.
I only hope that I threaded things back correctly. As it stands when focused to infinity the rear of the outer lens barrel (the the aluminum ring secured by the four amazingly easy to lose set screws) is in contact with the focusing gear that interacts with the range finder focusing knob. Is that correct?
Wow, lots of questions for this old and curious camera.
Thanks Dave, and all who will yet reply,
I use Corning vacuum grease: it doesn't dry out or separate into oil that migrates to the aperture blades.
Nicholas' suggestion sounds like an excellent idea. I did a "CLA" a couple of years ago and I honestly don't recall whether I used some silicon grease or some white lithium stuff I had around. Either is probably less than the optimum, but I didn't use very much. My only use of the camera has been the last three "Argus Days." And the organization of that event appears to have somewhat disintegrated this year (so it may not get used again!)
Sponsored Ad. (Subscribers to APUG have the option to remove this ad.)
I use a synthetic grease called "Super Lube" on helicals. Keeps everything nice and smooth.
Check it out here.
WD-40 is wonderful in many applications, but keep it away from cameras. It appears to be a very thin penetrating oil. However, when the thin solvent evaporates, only a greasy substance remains. This can really gum up a camera.
Maybe Bradd's Argus is an example of such abuse. Fortunately, many of the two million "bricks" still exist, providing plenty of repair parts.
I have come to the conclusion that there is little I can do with my lack of camera expertise to fix the aperture. But I really do like the Argus, so I think I'll eventually pick up another.
Thanks for all your help,
Having restored a number of pre and post WWII german made microscopes that were lubed with something that resembles blue loctite after 60 years is:
A.: Warm up the lens or mechanism to 100-120F, you can use more heat on unpainted or on parts not containing optics. The heat softens the rock hard grease and then you can get the part moving. Sometime that is all it takes to "unglue" the parts..
B.: Next step, slightly more drastic, is apply a very small drop or two of ronsonol lighter fluid to the gap between the parts. It will wick in and just might soften up any grease that is under the ring so it will move.
Otherwise, a soak in a mix of synthetic motor oil and lacquer thinner works well on unpainted non optical parts like gear trains and large bevels. Not recommended for lenses.
You can sell it on to someone willing to futz with the aperture.
Originally Posted by Bradd Cluckey
you can sacrifice it to the cause of learning to fix cameras - and possibly fix this camera.
Argii are pretty simple, unsophisticated and hard to break cameras - not a bad place to start.