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PaulSchneider
3-Jan-2011, 16:19
Hi guys!

Following problem: I just bought a sinaron digital lens that's a few years from ebay. It has a copal 0 shutter. Whilst inspecting it, I realized that the shutter speeds are way off below 1/60th.

The nearer it gets to 1 second the slower the shutter gets. 1 second for example, is somewhere between 2 to 3 seconds.

Is this problem easily fixed or must the whole shutter be swapped?

Where or how can I fix this?

Kind regards

Paul

Leigh
3-Jan-2011, 16:25
Hi Paul,

It needs a CLA (Clean, Lube, and Adjust).

The slower speeds are controlled by an escapement, similar to the workings in a clock or watch. There are a bunch of gears in a train. The shafts ride in simple holes in the plates; no jewels involved. With age and use the original lubricant dries up, migrates, or gets gummy. The escapement needs to be cleaned and re-lubricated.

Any competent repair shop can do it.

S. K. Grimes at http://www.skgrimes.com/repair/repshut/index.htm is highly recommended. I have no personal experience with them.

- Leigh

PaulSchneider
4-Jan-2011, 08:18
Leigh,

thank you very much! I'm glad it isn't a huge problem ... I called a local repair shop and they said somewhere between 100 and 200 usd ...

I'll remember that: CLA!

Kind regards

Paul

Robert Ley
4-Jan-2011, 17:45
Paul,
That seems like a very high estimate for a simple CLA. Check the forum and you should find several places to send your shutter out. Most places charge between $50-80 for a simple CLA which this sounds like one. I am sure other forum members can give you contact info for several if you can't find it in a search.

Neal Chaves
6-Jan-2011, 15:50
I watched a very good repair technician CLA many shutters when I worked for the Navy in Hawaii. The man, John Simms, was semi-retired and just doing this work for some extra money. He worked in Hollywood for many years as a photographer and photo-optic technician after he got out of the Army Air Corps. Have you ever seen the photos and films of the Ploesti Romania raid?
http://www.americainwwii.com/stories/raidinruins.html
John Simms was in the nose of the last B-24 to cross the target with a K-20 camera to document the damage inflicted. He was still picking out shrapnel thirty years later.

Mr. Simms would pull off the face of the shutter and wash out the mechanism with solvent. In those days he used freon, but today a good residue-free gun cleaner or brake cleaner can be used. If the slow speed gear train was especially gummy, he removed it and put it in solvent to soak. When all was clean, he dusted the mechanism with graphite lube and cycled it until it ran smoothly and the excess graphite fell out with some gentle puffs of canned air. Our shutters always ran perfectly afterward, and never failed. You might try this for practice on an old shutter.

Leigh
6-Jan-2011, 16:07
...he dusted the mechanism with graphite lube...
If anyone chooses to repair a shutter, please DO NOT use graphite. It was considered a good lube until we learned of its abrasive properties.

Graphite is comprised of pancakes that slide against one another. That works well as a lubricant. But when they stand up on edge they're highly abrasive.

Modern doctrine calls for use of molybdenum disulphide ("moly lube") for all running surfaces.

Moly is comprised of little balls that lubricate well regardless of their orientation.

The gear stems in the escapement should receive a very small amount of a high-grade oil. I use Astro Oil from William F. Nye (unfortunately no longer made). At $90 an ounce, I still have most of the original supply.

Suitable lubricants are available from Micro-Tools, the main supplier of repair parts, tools, and supplies for the camera repair industry. http://www.micro-tools.com


- Leigh

Neal Chaves
6-Jan-2011, 20:54
I haven't had to open up a shutter in a number of years since phasing out of Compounds and Compurs into Seikos and Copals. They have been trouble free, but you're right about the moly lube. I have some right here and that's what I would use. You can buy it any gun shop, Birchwood Casey brand.

The best oil was sperm whale oil, and the government had lots of it at one time for the gyros in missiles. Some may still be available on the surplus market. If you can find a suitable replacement that won't gum up, that's good, but as you know the quantity has to be minute and applied with a needle oiler. If it ran well with just the dry lube, I would leave it alone, especially if I sometimes worked in the cold.

Nathan Smith
6-Jan-2011, 22:06
Two favorites are Carol Flutot Miller & Paul Ebel. I have have sent work to both of them and been quite pleased with both, and I've never heard a bad word about either of them. I think that either one of them would likely be cheaper than your local guy quoted you.

http://www.flutotscamerarepair.com/

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