Shutter repair - Mamiya-Sekor 100mm f3.5

It is pretty easy, Mamiya Press lenses, apart from the 50mm, take regular standalone leaf shutters. A size 0 Seikosha/Seiko/Copal of similar age and build should do the job - it must be similar, as you'll have to transplant the trigger arm, otherwise it is a cell/shutter change as on any large format camera.
 
It is pretty easy, Mamiya Press lenses, apart from the 50mm, take regular standalone leaf shutters. A size 0 Seikosha/Seiko/Copal of similar age and build should do the job - it must be similar, as you'll have to transplant the trigger arm, otherwise it is a cell/shutter change as on any large format camera.

Do you know of any resources online that I can use to order that parts needed and instructions to do this?
 
Well, I got the lens today. I disassembled the front of the lens and got to the shutter mechanism. Wow, looks like a watch!!! After careful inspection of the mechanisms, I found roughly where I needed to put my attention. I found the piece that closes the shutter and after using a screw driver to close it, the mechanism started working. I can now cock the shutter and fire it successfully!!! However, if you look at the eBay photo, you will see that one of the shutter leafs is misplaced. This piece remains permanently open. Due to this, it is impossible to shoot at aperatures f16 and wider as lots of light leaks in. If I close the aperture down to f22 or f32, no light (or very little) leaks through, allowing me to use the lens. Thus, as it stands, this is a f22-f32 lens only. Not bad for a grand total of $19 USD.

With further experimentation, I cut a credit card in a crescent moon shape with the middle shaped like the shutter blade. I then put on the front element. However, the element gets really close the the shutter, thus pushing the credit card into the other leaves, make this fix unworkable. I also tried not screwing in the front element all the way so it does not bend the credit card. This worked fine and focus wasn't that far off. However, the light still did leak. I was able to take a picture at f3.5 however with not too much damage. I was shocked that I had a full image though, as the credit card covers up about a third of the lens hole area.... Any suggestions on how to fix this further? I don't have a lens spanner, so I can't unscrew the rear lens element to try placing the credit card there.
 
Well, if anyone knows the Mamiya parts availability

Well, if anyone knows the Mamiya parts availability

It may be Tony (Anthony) Sansone. Has been referred to as the "guru" of the Mamiya Press system and the Polaroid 600 and 600SE system (built for Polaroid by Mamiya).

I've purchased parts (new) from Tony for the K-type Mamiya film back and talked with him about the system. He rebuilds and refurbishes these systems.

Link to a few pages from his older site.

http://members.cox.net/gmhsint/

He's in Florida and is heavily involved in the family Olive Oil business, Kreta Reserve, which also has a web site.

Regarding the lens helical, shutter and glass, there are usually multiiple examples of these at any given time on eBay selling from $75 to $100. They are 6X9 format lenses and do not cover larger formats, although they come close on 6X12 panorama. The shutters are extremely durable, so many survive for sale.

I just bought one on eBay which had been dropped and hit hard enough to bend the helical so it would not turn. Took the shutter out of the helical, and it worked flawlessly and is running within spec on all shutter speeds. I recall paying $35. The glass was good with clean, clear optics.

Good stuff by Mamiya.
 
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However, if you look at the eBay photo, you will see that one of the shutter leafs is misplaced.

If it is merely misplaced (and the picture looks like there might be no leaf missing), all you have to do is to re-sort the leaves. I vaguely remember a Mamiya Press lens manual being listed in the catalogue of one of the big camera repair manual copy sellers advertising on ebay - if that should not go into the details of the shutter, the same sources might also have Seiko or Copal manuals. And as a last resort someone or other on the Classic Camera Repair forum (http://www.kyphoto.com/cgi-bin/forum/discus.cgi) is almost bound to have rebuilt that shutter and will know the leaf count and ordering. But very few there write nice documentation (most notably Rick Oleson), the notebook descriptions by the majority of members tend to be extremely terse - often little more than two or three rough drawings or underexposed photographs, with a bit of poorly translated technological terminology from a very foreign language to go with it...
 
Well, all the leaves are there. I managed to rearrange 4 leaves and have them move smoothly. However, as soon as I get in the fifth leaf, the operation starts jamming. Also, I can no longer get the shutter to fire. The lens cocks and fires, but the leaves do not move. I can manually move them by moving the leaf holder ring. I am going to disassemble my 127mm lens on the Polaroid 600 to see if they are similar and if I put something together wrong, as well as the leaf order.
 
Micro Tools have a wide variety of lens spanners. Get one with flat, interchangeable tips rather than the more affordable crude black iron affairs - the latter tend to slip and foul up the ring or even damage the lens...
 
Micro Tools have a wide variety of lens spanners. Get one with flat, interchangeable tips rather than the more affordable crude black iron affairs - the latter tend to slip and foul up the ring or even damage the lens...

Thanks for the link, I'll have to get one of those tools. I managed to take off the retaining ring with a careful application of flat head screw driver and record clamp. I reorganized the leafs, but ever time I try to reassemble the shutter, the leafs fall out of place. I've given up for now, will work on it more when I feel more rested. Meanwhile, I removed the shutter off the 127mm lens on my Polaroid 600 (non SE) and put it on the 100mm lens. I also switched out the aperture rings so it displays the proper amount. I have a fully functional lens!!!!

I will be wanting to sell the Polaroid 600 camera now that I am using the Universal Press, but I will need to get it fully functional prior listing it. Anybody know where I can find a Seiko 0 or similar shutter?
 
I would like to thank the RFF members for coming to the aid of the OP on this question. It is something that I knew little about, and added to that knowledge by reading the thread.
 
Thanks everybody, the shutter is back together and working!!!! I just need to attach the aperture control dial and some more minor parts and I'll be able to put it back on the body. I took some shots with the 100mm lens and the things is super sharp and glass is very clean. Probably the best $20 I've spend on photo gear.

As a side note though, I did end up with some "extra" springs. My guess is it had something to do with flash sync, M/X, but as I don't use that it won't be a concern. It might even work, but I have no way of testing.

Thursday I purchased this legendary lens:

http://cgi.ebay.com/ws/eBayISAPI.dl...18415&ssPageName=STRK:MEWNX:IT#ht_2671wt_1141

I will probably transplant the best shutter into it and then get to work on cleaning this one.

I fear my before controlled mad scientist persona is starting to take a hold of me. I nearly burst into a diabolical laugh the moment I saw the reason behind shutter not firing and succeeded in a complete shutter cycle.

My goodness I love manual cameras!
 
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