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Strange Graphex Shutter Behaviour

 
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CrownVienna



Joined: 04 Aug 2012
Posts: 5
Location: Vienna, Austria (Europe)

PostPosted: Sun Aug 05, 2012 12:14 pm    Post subject: Strange Graphex Shutter Behaviour Reply with quote

Hi all,

I'm Georg from Vienna, and I am new to large format fotography. A friend of mine, former press photographer in LA, gave me his Graflex Crown as a present. Currently I am experimenting a lot with it, and found a strange behaviour:

The lens I am using at the moment is a Graflex/Wollensak 4,7/135 Optar in a Graphex shutter. It works fine at all speeds, except I have a strange problem when I want to do long time exposure set to "B".
When I set the shutter to "B" and use a cable release, the shutter closes after 2-10 seconds again - no matter if I keep the cable release pressed manually or if I use the locking mechanism.

Same happens when I trip the shutter via the shutter release on the camera frame, or directly on the lens.

Can somebody offer an explanation, or even better, a hint on how to solve that?

Thanks

Georg
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Henry



Joined: 09 May 2001
Posts: 1636
Location: Allentown, Pennsylvania

PostPosted: Sun Aug 05, 2012 4:02 pm    Post subject: Reply with quote

Since the behavior happens when the shutter is tripped with the release lever, and with the cable release, it's probably an internal problem with the mechanism. The shutter will undoubtedly need to be disassembled, as there are several possible causes for it. I certainly would seek out a skilled repairman for this job. You can learn more from the Graflex factory repair manual "Graphex Shutters," available here from http://www.photobooksonline.com/books/manual03.html (item #90026).

One thing you could try: file the plunger end of your cable release perfectly flat, to make sure it's not slipping off of the inside lever tab. I've done this with my cable releases, to good effect. If it renders the "B" setting useable, it will spare you the headache of getting it fixed. Otherwise, you can just use the "T" setting---not as convenient, but at least it will give you the long exposure time when you need it. But if the "T" setting behaves the same way (it's called "Shutter goes through time and bulb settings" in the repair manual) you'll certainly need to pursue the repair option.
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CrownVienna



Joined: 04 Aug 2012
Posts: 5
Location: Vienna, Austria (Europe)

PostPosted: Sun Aug 05, 2012 4:49 pm    Post subject: Reply with quote

Henry, thank you very much!

The T-Setting works just fine, so this can be my workaround.

I am quite good at fixing fine mechanical stuff, but with an unknown apparatus I am always very careful. I will eventually order the repair manual and give it a try, as workforce is expensive here and the (professional) repair will likely cost more than the whole thing is worth.

Thanks

Georg
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Henry



Joined: 09 May 2001
Posts: 1636
Location: Allentown, Pennsylvania

PostPosted: Sun Aug 05, 2012 5:40 pm    Post subject: Reply with quote

Bitte.

Henry
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45PSS



Joined: 28 Sep 2001
Posts: 4081
Location: Mid Peninsula, Ca.

PostPosted: Sun Aug 05, 2012 7:43 pm    Post subject: Reply with quote

http://www.southbristolviews.com/pics/Graphic/manual-pdf/GraphexShutterService.pdf
is a free copy of the service manual.

The shutter is in need of a CLA. It will suffer unrepairable damage if it is not serviced. The Graphex/Rapex shutter is not as robust as some other brands of shutters.

The only problem you should have is with the terminology of the parts and flipping pages to see the diagram referenced to in the instructions.

This thread http://graflex.org/helpboard/viewtopic.php?t=6103 shows a #2 Graphex shutter fully disassembled. The shutter you have is a #2.
This thread, http://graflex.org/helpboard/viewtopic.php?t=6105 is a simple to make/use shutter speed tester.
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Henry



Joined: 09 May 2001
Posts: 1636
Location: Allentown, Pennsylvania

PostPosted: Mon Aug 06, 2012 5:15 pm    Post subject: Reply with quote

Georg, one other thing you can try. Over here it's referred to as the "Ronsonol soak" (Ronsonol is naphtha, used as cigarette lighter fluid; Zippo markets, or did, a similar product). Remove front and rear lens elements (they unscrew counter-clockwise) and squirt Ronsonol into the works, then cock and release the shutter through all of its speeds. This will help to loosen up the schmalz and schmutz from the moving parts, and may restore the bulb function---or maybe not, depending on the cause. Of course this will not correct any mechanical problems, such as bent levers or broken springs, but it's worth a try. Doing this has improved the performance of all of my Graphex shutters (I own six of them).
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CrownVienna



Joined: 04 Aug 2012
Posts: 5
Location: Vienna, Austria (Europe)

PostPosted: Tue Aug 07, 2012 10:27 am    Post subject: Reply with quote

So, thanks for the links and tipps.

I took the shutter apart yesterday and cleaned it. I did it carefully with a fune brush. As I did not find any dry lubrication or sticky junk, I refrained from using any solvents. I thoroughly cleaned all the posts that go into the guides for speed setting.
I also had found on disassembly that one spring had jumped out of its seating.

After putting everything back together it now works very well on all speeds (shutter times within the design's limitations), and also B works stable.

Thanks for your help!

Georg
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