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Subject: Sputnik Shutter
Date: 2016-02-19 18:05:30
From: iandvaag
Attachments :
I've been working on a number of sputnik modifications/repairs over the past few days thanks to the numerous posts in this forum. I've got the lenses opened up now, and I've been working on a shutter problem. My sputnik's shutter worked fine on 1/125, 1/60 and 1/30, but often it failed to close on 1/15 or bulb. I would have to manually push the shutter cocking lever to its closed position. I was hoping to fix this.

Problem is, now I've got the lens opened up, and after tinkering around and cleaning with some naptha, the shutter will no longer fire at any shutter speed. I can cock the shutter, but it won't fire.


Photo 1

The only way I can uncock the shutter currently is to detach the green spring from the (green) "shutter arm", as is shown in the first photo. Pressing the shutter button after detaching this spring uncocks the shutter without actually opening the shutter blades.


Does the (red) tab open the shutter leaves?  This tab appears similar to the tab which actuates the slave shutter on the left eye.


Photo 2

When I press the shutter release, the metal leaf (blue) under the "slave shutter plate" (purple) deforms slightly. I believe this whole plate and the brass pin inside it must move downward to open the shutter. Any way to stop this assembly from binding?  Is there any known issue with the shutter leaves binding?


Any tips? Also, how does one remove the self timer? Mine seems to be working, but I'd rather not have to open up the lenses again when (not if) it goes bad.


Thanks,

Ian

Subject: Re: Sputnik Shutter
Date: 2016-02-20 19:01:13
From: efbaskin
My tip would be to buy a cheap Lubitel from eBay and use that shutter to replace the broken one that you have. They're the same.  I might even have a spare one that I can give to you.  Trying to fix the one that you have could very well be a waste of your time.

As far as the self-timer, I think it can just be lifted straight up and out. 
Subject: Re: Sputnik Shutter
Date: 2016-02-24 01:16:55
From: iandvaag
Attachments :
    Well, it turns out that something is grinding between the aperture blades and the shutter blades, thereby not allowing the shutter to fire properly. I'm not sure if the aperture blades are directly grinding against the shutter leaves, or if there is some junk in between them -- it's too hard to see.

    Thanks for your advice Ted. I successfully removed the self timer. I'm going to try a bit more, but if I can't get it to work, I'd like to take you up on your offer for the lubitel shutter if you've got one. If I were to change out the shutter, how do you go about removing it? I found an article online about the lubitel, I assume it would be the same: http://www.jdavidbuerk.com/blog/708

    I'm pretty sure the author of this article suggests that you have to hold the red ring in place while turning the blue ring. I don't see how you can hold the red ring without scratching the rear lens element. Any tips?

    One more thing: I found a graphic of the sputnik lens layout, I was wondering if the spring in green is in the right place. Looking at the graphic, I'm not sure the spring is supposed to be hooked around the "shutter release arm". Any ideas as to where this spring goes?

    Thanks as always.
    Subject: Re: Sputnik Shutter
    Date: 2016-02-24 08:09:52
    From: efbaskin
    The red ring is part of the lens/shutter assembly "basket" (for lack of a better term). So, by holding the entire lens/shutter assembly from the front, you are effectively holding the red ring in place.

    I won't be home until this weekend, so I can't answer your other questions right now. Sorry!
    Subject: Damping Grease (WAS: Sputnik Shutter)
    Date: 2016-03-31 00:04:36
    From: iandvaag
    Thanks so much for your help Ted! I got everything apart and found that one of the shutter leaves was broken. I changed the position of the broken leaf so that it wouldn't bind on the brass pins of the aperture blades and jam the shutter anymore.

    Now just a matter of putting Humpty Dumpty back together!

    I've been searching through the forums as to any other modifications I may want to do while I've got the lenses opened up. I'm planning to epoxy on a piece of brass tubing to force the slave shutter to close in sync with the master shutter as Jeff Pierce wrote about on his web page. After that I've been wondering about using some high viscosity damping grease to prevent the lens elements from rattling around. I have a few questions about this:

    1. What is a suitable grease? It looks like the best options are Nye Lubricants damping grease or ROCOL Kilopoise damping grease. Unfortunately it is very difficult to find either of these at a reasonable price. Any other suggestions?

    2. I've only ever read about people using this grease on the threads of the front Sputnik element. Would it be acceptable to use it around the edge of the middle (and rear) elements where it would come into direct contact with the glass? Alternatively, Richard Rylander used a thin black paper collar under the retaining ring and Paul Bigelow used small drops of flat black paint around the cir-clips to "lock" the lenses in place as it dried. If the grease is not appropriate for the middle elements, I'm leaning towards using a thin strip of flocking paper below the cir-clip. I suspect this might also help to further reduce internal reflections (I already used a sharpie to blacken the middle element edges).

    3. How much grease would I need? I don't suspect it would take much. Would 10 grams be sufficient?

    Ian
    Subject: Re: Damping Grease
    Date: 2016-03-31 11:18:33
    From: John Thurston
    On 3/30/2016 10:04 PM, iandvaag@gmail.com [MF3D-group] wrote:
    - snip -
    > 1. What is a suitable grease? It looks like the best
    > options are Nye Lubricants

    I bought a tube of Nye when I did the lenses on my Sputnik.
    Silicone grease is now more common than it used to be. If
    you are feeling daring, it is available at the automotive
    stores in a tiny tube or tub. It is sold as a dielectric
    grease, or as a weatherstripping grease. The danger here is
    it may contain something other than silicone, which may
    outgas and leave deposits on your lenses.

    > 2. I've only ever read about people using this grease on
    > the threads of the front Sputnik element. Would it be
    > acceptable to use it around the edge of the middle (and
    > rear) elements where it would come into direct contact
    > with the glass?

    It is a grease, meant to promote smooth movement. I would
    not try to use it as a glue to prevent movement.

    > 3. How much grease would I need? I don't suspect it
    > wouldtake much. Would 10 grams be sufficient?

    Tiny amounts. 10g would be lots and lots.

    --
    John Thurston
    Juneau, Alaska
    Subject: Re: Sputnik Shutter
    Date: 2016-03-31 11:32:49
    From: iandvaag
    Great, thanks so much John. Do you remember which type you got? There's a list here. I am trying to decide between the Fluorocarbon gel 868VH or the nyogel 774VH (VH for very heavy). There both reasonably priced in 10g tubes.

    Ian
    Subject: Re: Sputnik Shutter
    Date: 2016-04-18 00:24:09
    From: iandvaag
    Attachments :
      I've fiddled around around quite a bit with the shutter, and have mostly got things working. I ordered a tube of nye damping grease for the front element and am now ready to reassemble the lens. I have one more modification I'd like to do while I've still got everything open and apart.

      I have found that there is a slight (but noticeable) difference in shutter speeds between the two lenses at 1/125, so I was planning to modify the shutter link as described by Jeff Pierce at the bottom of this webpage. I found a suitable brass tube to act as a sheaf over the slave shutter post, but I can't for the life of me figure out how to connect the shutter link to the post of the master shutter (see  green post on images). Jeff said he used a circle of wire, but unfortunately had no photo of this. Can anyone explain how this would be done? The post is short and extends only a fraction of a millimeter above the red "mounting plate". How do I attach wire to this post with such small clearance? There is a groove on the post to position the return spring. What kind of stiff wire could I find that could go in this groove?

      Note that I am holding the shutter open on bulb in these photos. The shutter link tab has to be on the left of the post. My goal is to couple this tab to the post, such that when the return spring of the master shutter pushes against the master shutter post, the tab of the linkage is pulled along with the post.