Tight aperture ring

[David]

I just received my 'new' 14" f4.5 Heliar and did some testing with it today. Too cool, I think. Anyway, the aperture ring is very stiff and I'm wondering if there is some home remedy for this. I thought maybe something like menthylated spirits, or turpentine might flush any old stuff out but I'm not about to use this jewell of a lens for experiments.

Thanks for your suggestions.

[joeyk49]

Time for a CLA...I had the same experience recently. I bought my first LF camera (4x5 Crown Graphic) who's shutter ring was really tough to turn up to the higher speeds. Unless you know what you're doing (which I don't), don't mess with it and send it to a reputable repair person. I sent mine to a fellow APUGer, who has her own repair business in California and was very pleased to get my shutter back in less than two weeks with the action working 100% better. I'm sure that there must be a good repair shop a little closer to you.

[David A. Goldfarb]

Presumably, this lens doesn't have a shutter, so you're only talking about cleaning the aperture blades and mechanism. If you're confident about such things, you can disassemble the diaphragm and flush it with naphtha, taking particular care to note how the blades are assembled and how they overlap. This only applies to metal parts (which I think these diaphragms are--I haven't had to clean mine yet). If there are layers of paper or vulcanite blades (unlikely), don't soak these in naphtha.

Usually the blades have pins and these pins move in slots that are in an adjustment ring, and it's the friction between the pins and the slots that make the aperture stiff (unless there is something like oil on the blades). If the entire thing is made of metal, you might be able to get away by soaking the whole diaphragm assembly in a solvent without taking it apart (and saving the sometimes difficult task of reassembling the blades). If it's necessary to lubricate the pins, you can use a light grease. It probably isn't necessary to lubricate the diaphragm blades, but if you want to, you could use a dry graphite powder lubricant.

[jimgalli]

David, Congrats on a nice purchase. I usually just take some alcohol and a q-tip. Get the q tip good and soaked and just start working around the aperture exterior ring next to the barrel. The Q tip will "wick" a lot of old dry oily muck out. Do the same thing on both sides. Most of the time the friction is just below the surface and will get freed up as you work it a bit.

[David]

Thanks for the responses. Yes, we have no shutter, just the aperture blades. I tried rotating it numerous times but it didn't release itself that way. I think I'll try the Q-tip alcohol route as I don't want to soak anything that shouldn't be soaked or take it apart if I don't need to. I'll post the results.