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resummerfield
2-Apr-2005, 23:07
Whenever I acquire a new lens (a used lens, but new to me), I’ll clean it externally and check the speeds (I have a small Calumet shutter tester), and that’s all. I’ll use the lens for years with no other maintenance, unless I know something is wrong.

Obviously, the best course would be to send all my lenses off for professional preventive maintenance, probably yearly. But realistically, that’s just too expensive and time consuming. And I would be without the lens for weeks. So I was wondering, how difficult would it be to perform routine maintenance myself? Not to disassemble the individual lens elements, but just an internal clean and lube of the shutter? In reading some back posts, it seems others have been doing just that.

So how about some feedback: Who does perform their own CLAs? Where did you learn how? And most importantly, give me some suggestions on acquiring the basic knowledge of shutter maintenance.

On a related subject, someone relayed to me advice from his repair shop, that the best way to store a lens was with the aperture open, and the speed on T with shutter open. He said it released tension on the springs. Has anyone else heard of this? Does anyone have a special way to store their lenses?

Guy Boily
3-Apr-2005, 09:15
Eric, Lens repair is uncertain territory. I acquired several old and very good lenses from an estate not to long ago. I did get them for a really good price but most of them were so old they were gummed up. Getting them fixed costs an arm and a leg. I have a talent for repaing just about anything so I figured, what the heck I'll give it a try. That 1st lens must have been disassembled and assembled about 20 times but I finally got it to work perfectly. The shutter is crisp, the timer seems accurate. I made a few prints with it (4x5 format) and it's great. I followed the recommendations on a few sites to get me started. Here is one of them: http://www.kyphoto.com/classics/articles.html
Try it out on a old lens and take a chance. It's not for everyone. The parts a very very small, the shutters blades are a blast to put together and sometimes the springs do fly around.
Good luck
www.guyboily.com

Paul Fitzgerald
3-Apr-2005, 10:48
Hi there,

If you want to service your own shutters it is easier to buy a 'beater' twin first to play with. Every manufacturer had completely different styles, every model is different and there are major & minor differences by date. See if you can scan ebay to find a service manual for the specific shutter and read it end to end twice before starting. The easiest shutters are Ilex #3 universal, Wollensak Alphax #3 and Kodak Supermatic #2.

Advice:

It's cheaper to have a professional do it.

DO send Copal, Seiko, Prontor Pro, late Compur, Graphex 1000 and Rolleis to a professional that specialises in them.

Forget Volute, Optimo, pre-war Ilex shutters, any shutter with plastic blades.

DO NOT 'flood clean' a shutter with solvent, that's the last step before the trash bin. This will only move the dirt around to places it could not get before, can destroy the blades and will damage the paint work.

Have fun and Good Luck with it.

Michael S. Briggs
4-Apr-2005, 23:29
In amateur use, modern shutters don't need yearly maintaince. I don't have CLAs done on my shutters unless they operate irregularly or deliver times significantly different from the marked value. Typically the first thing to go is the slow speeds become too slow, from congealed lubricant.

If you want to learn how to work on shutters, figure that you will probably ruin the first that you work on.

The main thing that tensions springs is cocking a shutter. But a properly designed spring will be in the elastic regime even when cocked and won't suffer. Many photographers feel more comfortable storing their shutters uncocked, but it probably doesn't make much different.