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Tim Deming
11-Dec-2012, 09:29
I know this is a long shot, but I've got a small, old compound 00 shutter (holds a 132mm f6.8 Collinear III) that came to me in pieces. Fortunately, I have most of the pieces and have it together again. The problem is the main spring (that is tensioned when cocking the shutter, and housed within the cylinder that the cocking arm mounts to -labeled as #4 in the image) is missing. Looks like someone a long while ago took it apart to get to this problem, and then gave up. I've worked on most every type of shutter, but never had to replace the main spring on a compur or compound before. Anyone with this experience here? Is it tricky to tension and install this spring?

I do have a larger, working compound I'm tempted to cannibalize for the spring, but want to make sure I dont decommission that if the spring wont fit (the winding mechanisms do appear to be similar is size and structure). Any help (including a cheap or donated broken compound for parts) would be appreciated.

thanks

Tim

85258

E. von Hoegh
11-Dec-2012, 10:43
Your best bet is a similar shutter for parts. To duplicate the spring, you'd need the original for dimensions; it's not that horrendous a job if you have length width and thickness.

edit - Do not try to use the spring from the other shutter. You will almost certainly end up needing two new springs.

Steven Tribe
11-Dec-2012, 12:02
Does the spring reside in the round housing with the threads for attaching to the lever?
I have a number of scrap compur/compounds from 9x12cm folders and I think that many parts are the same size. Will check in good daylight tomorrow.

E. von Hoegh
11-Dec-2012, 12:19
Steven,
The structure at 3 o'clock in the larger view houses the spring, it's a relatively thick flat spiral of around 4-5 turns and the spring itself is not visible.

I'm not certain but I think the Compurs had a stronger spring.

Tim Deming
11-Dec-2012, 14:12
Does the spring reside in the round housing with the threads for attaching to the lever?
I have a number of scrap compur/compounds from 9x12cm folders and I think that many parts are the same size. Will check in good daylight tomorrow.

Yes, that's right, inside the approx. cylinder shaped housing that the cocking lever mounts to (marked "4" in the big image). Upon not too close inspection (i.e. I didnt remove the cylinders) of a few compounds and compurs, it does look like this housing (and/or spring inside) was fairly standardized for these shutters. Spring strength changing with compound vs compur and for different sizes is a good point, but I'll gladly try out any spares you can send my way :)

cheers

Tim

Tim Deming
11-Dec-2012, 14:14
edit - Do not try to use the spring from the other shutter. You will almost certainly end up needing two new springs.

Why? are they prone to breakage, or that difficult to remove?

cheers

Tim

Steven Tribe
11-Dec-2012, 15:54
The cocking spring of all the dial set compurs I have had, did have noticeable different tensions, without the function being much influenced.

E. von Hoegh
11-Dec-2012, 15:56
Why? are they prone to breakage, or that difficult to remove?

cheers

Tim

They're tricky to remove and reinstall without stressing the spring, which can cause it to break.

Steven Tribe
12-Dec-2012, 04:49
OK Tim, I have a "scrap" small compound that was sold by Goerz - I have taken out the Series III 120mm (?) cells long ago.
I feel pretty sure that this is the same size as yours ( external diameter 55mm).
There is is working spring in the housing.
Do you want this as a complete shutter (the dial and cocking lever/screws are gone) or would you prefer me to take out the housing + spring?
One disadvantage with the "complete" shutter is the US customs! Or you could send the remainder to our favorite shutter repair gal!

Tim Deming
12-Dec-2012, 08:41
Thanks Steven,

this looks perfect. Probably best to have the whole thing. I can either see how the spring is mounted now, to help reinstallation, or even rebuild your shutter with parts from mine if the threads are the same.

cheers

Tim

Steven Tribe
12-Dec-2012, 09:08
On it's way. This is not a commercial activity in any way (for Moderators)!
I doubt the shutter (mine) is worth the effort! The main spring has tension, but everything else seems totally locked. Dismantling screws are good.

Tim Deming
12-Jan-2013, 15:08
Update!
I received the donor shutter from Steven (many thanks!) and have successfully taken its main spring and installed it in my dead compound shutter. The spring removal and installation is straightforward. It installs as a cartridge unit, that is easily tensioned once installed, so no worries about breaking the spring or trying to adjust the tension. I’ve attached a few picts showing the spring mounting, and the final result. Sorry for the shaky picts, I was handholding in dim light.
Pic 1: This is Steven’s shutter, disassembled with the spring cartridge removed and sitting to the right. Quite a lot needs to be disassembled to get to this point, but it’s pretty obvious what needs to be removed to get to the spring mounting screws. The most important things are keeping track of the order of disassembly, remembering where everything goes (and noting that no screws are interchangeable), and having a good set of screwdrivers.
Pic 2: Back of my shutter, with old spring cartridge still in place, and replacement ready for installation. It’s worth noting that Steven’s shutter, although the same size compound from similar era, was slightly different from mine, and I had to file a few parts so the replaced spring + housing fit properly with the various linkages from my shutter.
Pic 3: my shutter, with most of the guts reassembled, remounted spring is at 3 o’clock
Pic 4: fully assembled, and back in camera! A bit of adjustment on the retardation spring (wire near the top right in Pic 3) allowed adjustment of shutter to get the speeds close to spot on.

cheers

Tim87224872258722687227

Steven Tribe
13-Jan-2013, 15:13
Nice Alpin!
A very worthy new "home".

Ron (Netherlands)
28-Dec-2016, 03:58
Just found this 'old' but very informative thread because I was in search for members who had replaced a broken spring in a Compound or Compur shutter. Have a shutter comparable to that of Tim, albeit a little bigger. It seems to be a # 2 or 3 with a very nice Tessar. The shutter is complete but came with a broken spring which was still inside.
Might be a long shot but if anyone has such a shutter for parts I would be interested. Here some pictures of the shutter and its broken spring.

http://kpmg0072.home.xs4all.nl/Compound/20160926_104654.jpg

http://kpmg0072.home.xs4all.nl/Compound/Compound%201908.jpeg

Steven Tribe
28-Dec-2016, 07:52
I'll have a look before the new year and get back to you.

Ron (Netherlands)
29-Dec-2016, 15:19
Many thanks Steven,
and happy holidays!

Tim Deming
3-Jan-2017, 01:32
I'll have alook as well once I'm home in a couple days. You might need a new cocking lever as well, since the levers mounted with 2 screws are much less common vs. those mounted with 3 screws, so finding a spring with a 2 screw mount could be difficult

Cheers

Steven Tribe
4-Jan-2017, 04:07
I didn't find anything of the right size, unfortunately!

Ron (Netherlands)
4-Jan-2017, 12:57
I didn't find anything of the right size, unfortunately!

Thanks anyway for searching!

Ron (Netherlands)
4-Jan-2017, 13:00
I'll have alook as well once I'm home in a couple days. You might need a new cocking lever as well, since the levers mounted with 2 screws are much less common vs. those mounted with 3 screws, so finding a spring with a 2 screw mount could be difficult

Cheers

Thanks Tim, indeed this one has the 'old' 2 screw lever - but in my box of spare parts I must have a 3 screw lever waiting to be used again....

Tim Deming
6-Jan-2017, 20:00
Sorry, no parts either. I do have an intact, fully functioning B&L compound with a 3.5x5.5 B&L tessar, that looks nearly identical to yours, but is likely a size smaller.

Ron (Netherlands)
7-Jan-2017, 03:45
Sorry, no parts either. I do have an intact, fully functioning B&L compound with a 3.5x5.5 B&L tessar, that looks nearly identical to yours, but is likely a size smaller.

...would be a pity to take out a spring from a fully functioning compound though.....
thanks for looking, much appreciated!

guess there must be some more broken compound shutters around.....