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bartbob
Joined: 30 Oct 2010 Posts: 102
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Posted: Wed Nov 03, 2010 10:45 am Post subject: Graflex 1000 Lens/Shutter Repair Guru? |
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Having just acquired a Super Speed Graphic with subject lens and shutter, I've learned it's shutter is often a reliability issue. Mine seems to be fine now, but who knows when it'll go off kilter.
When it needs adjusted or repaired, who's the guru to do such work?
Bart |
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sobahguy
Joined: 09 Oct 2001 Posts: 173 Location: Massachusetts
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Posted: Wed Nov 03, 2010 2:59 pm Post subject: Graflex 1000 Shutter Repair |
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Hi Bartbob...
I'm pretty sure that 45PSS has posted before that he has been able to clean/lube this particular shutter so long as it doesn't need any parts...I don't want to (nor can I) really speak to how intricately familiar he is with working on this shutter, though...perhaps he will weigh in himself on this thread.
If an CLA/REPAIR **WITH PARTS NEEDED** is required then follow the link below for Fred Lustig in Reno,NV... AFAIK he is the ONLY source for parts needed who is capable of fixing this problem-prone shutter. He has no internet/email so you will have to call him (please also allow for time zone differences). When you mention getting this shutter repaired he may grumble or grunt a bit but he is quite a nice guy by all accounts & has always been cool with me. He fixed my 1000 shutter for me several years ago and his workmanship & ethic is first rate.
Hope this helps...
Sobahguy...
http://graflex.org/news/lustig.html |
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45PSS
Joined: 28 Sep 2001 Posts: 4081 Location: Mid Peninsula, Ca.
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Posted: Wed Nov 03, 2010 8:06 pm Post subject: |
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Yes I CLA the Graphic 1000 shutter. Occasionally a broken shutter shows up on ebay. They make good parts shutters. Contact me via the site PM if you are in need of the service. The turning force and smoothness of the turning action are the only clues the shutter needs service. _________________ The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU. |
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bartbob
Joined: 30 Oct 2010 Posts: 102
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Posted: Thu Nov 04, 2010 12:36 pm Post subject: |
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Thanks to all for your replies.
That shutter seems to cock smoothly enough. But I've no reference on how much torque it takes to cock it. I could measure it then I'll have a number in inch-pounds, if that would be meaningful.
I'm about ready to make some shutter speed tests with an electric motor running at 1750 rpm. A pully on it painted black with a white dot at the edge under bright lights is how I tested the shutter years ago with my 2x3 Graflex. At 1/60th, that spot would make a half circle (175 deg., close enough) on the ground glass, plus a little bit more at the ends due to leaf transit time between closed-open depending on f/stop used making the ends taper down in brightness. Not exact, but close enough for me.
As long as it's good at 1/500th and slower, that's fine. At 1/750 and 1/1000 is where they seem to go bad first from what I've seen on the 'net. |
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45PSS
Joined: 28 Sep 2001 Posts: 4081 Location: Mid Peninsula, Ca.
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Posted: Fri Nov 05, 2010 6:29 am Post subject: |
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Quote: | ounce force (ozf or oz)
a traditional unit of force, equal to the force experienced at the earth's surface by a mass of one ounce. One ounce force equals 1/16 pound force or about 0.278 014 newton. |
Have you seen a scale that you hold on your finger tip and attach the object to be weighed on the other then you lift it up until the object to be weighed is not being supported by anything other than the scale? A similar device is made that you put on the end of a spring that is attached to a rigid post and pull the spring a certain distance or pull until the spring starts to move that is calibrated in ounces.
Taking such an instrument, attaching it to the cocking ring of the shutter, keeping it perpendicular to the lens shade and pulling on it causing the cocking ring to turn the scale should read 1 to 3 ounces which converts to
.75 to 2.25 inch pounds of torque. My arm/fingers have not been calibrated for over 30 years so I may be off .25 ounce.
When I was using inch pound torque wrenches regularly I could get to ± 1 inch pound of spec. without the torque wrench.
If a problem exists with a Graphic 1000 shutter it will most definitely show up at the faster speeds sooner than it will at the slower speeds. If the shutter blade eccentric gears had been made of brass or aluminum the shutter possibly would have been more reliable. The shutter blades are mylar. Any debris from gear wear or dried lubricant accumulates on the shutter blade plate and gets into the blade and gear pivots.
I have no experience with a dot on a pulley on a motor running at a known speed to test shutter speeds. I have heard of such.
http://download.cnet.com/Calculator-for-Science-Students/3000-2054_4-10893276.html?tag=mncol;5 _________________ The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU. |
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bartbob
Joined: 30 Oct 2010 Posts: 102
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Posted: Tue Nov 09, 2010 4:25 pm Post subject: |
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45PSS wrote: | Have you seen a scale that you hold on your finger tip and attach the object to be weighed on the other then you lift it up until the object to be weighed is not being supported by anything other than the scale? | Yes, I've got a pretty decent scale I could use.
But what part of the Graflex 1000 shutter is the "cocking ring?"
Is that what the lens hood threads onto?
I'm still learning "Graflex Speak."
Bart |
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45PSS
Joined: 28 Sep 2001 Posts: 4081 Location: Mid Peninsula, Ca.
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Posted: Tue Nov 09, 2010 8:59 pm Post subject: |
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The "winding knob" also functions as a lens hood and filter retainer.
The winding gear has a filter seat screwed into it (old style) and the newer version has it as 1 piece.
You should be able to cock the shutter by turning the winding gear but it will be substantially harder to turn than with the winding knob attached. All tensions I listed are with the winding knob/lens hood/filter retainer attached.
Graflex jargon only gets worse. _________________ The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU. |
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bartbob
Joined: 30 Oct 2010 Posts: 102
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Posted: Tue Nov 09, 2010 11:53 pm Post subject: |
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45PSS wrote: | The "winding knob" also functions as a lens hood and filter retainer. | That's what I wrapped a couple turns of friction tape on, then wrapped a cloth strap around it; put a loop in the end.
Four hours after posting this, I'm back to correct my math.....
It took about 40 ounces of weight on that strap to cock the shutter. With the radius of the tape to the lens center being 1-5/16 inch, that's about 3.2 inch-pounds of torque. (Reversed two formula items before; sorry 'bout that.)
Bart
Last edited by bartbob on Wed Nov 10, 2010 3:41 am; edited 1 time in total |
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45PSS
Joined: 28 Sep 2001 Posts: 4081 Location: Mid Peninsula, Ca.
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Posted: Wed Nov 10, 2010 12:05 am Post subject: |
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Time for a Clean and Lube, nothing much to adjust.
http://www.craigcamera.com/
#90025. CraigCamera Reprint: GRAFLEX 1000 SHUTTER 28pp, fully illustrated. Troubleshooting, disassembly, repair, and reassembly. EX reference, from Graflex original. $15.00
If you want to DIY. _________________ The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU. |
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bartbob
Joined: 30 Oct 2010 Posts: 102
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Posted: Wed Nov 10, 2010 4:04 am Post subject: |
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45PSS wrote: | Time for a Clean and Lube, nothing much to adjust. | Could be. Note I corrected my numbers; it's 3.2, not 1.9 inch-pounds. Oops!
Bart |
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45PSS
Joined: 28 Sep 2001 Posts: 4081 Location: Mid Peninsula, Ca.
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Posted: Wed Nov 10, 2010 4:41 am Post subject: |
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40 ounce-force foot=30 pound-force inch=2.49 pound-force foot. Too much torque.
40 ounce-force inch=3.3 ounce-force foot=2.5 pound-force inch=.208 pound-force foot. Upper limit of usable condition.
Shutter speeds will be correct until failure unless a section of the gear train is gummed up which occurs rarely. Leaf shutter speeds are considered good if the resulting exposure is within 1/3 stop. Shutter speeds measured at the center of the lens will be slightly longer than marked. Leaf shutter speeds measured from 1/3 open to 2/3 closed will be near correct. The first and last 1/3 of open/close is 3 to 5 stops less exposure than set aperture and has very little effect on total exposure. A leaf shutter when opening or closing at openings smaller than the adjustable aperture reduces the effective aperture resulting in less exposure for that time.
I cla ed mine about 12 years ago. It now takes about 10-15 ounce-force inch to cock. I will probably cla it again. I can cock it with the winding knob removed and it requires a tight grip in the winding gear. _________________ The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU. |
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bartbob
Joined: 30 Oct 2010 Posts: 102
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Posted: Wed Nov 10, 2010 2:00 pm Post subject: |
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That info on leaf shutter operation's well understood by me. I'm planning on using f/11 or f/16 to get the iris down to about 1/3 of its 30mm widest diameter clear aperture. My LED's ready to mount on a round disk to spin slow and fast.
Bart |
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45PSS
Joined: 28 Sep 2001 Posts: 4081 Location: Mid Peninsula, Ca.
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Posted: Wed Nov 10, 2010 8:50 pm Post subject: |
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135mm lens @ f4.5 aperture should be 30mm in diameter; @ f5.6- 24.1mm; @ f8- 16.9mm; @ f11-12.3mm; @ f 16-8.4mm; @ f22-6.1mm; @ f32-4.2mm.
Focal length divided by f number = aperture diameter; focal length divided by measured aperture diameter = approximate aperture number.
Aperture opening is measured as seen thru the entrance pupil (front lens element/group). Hard to get a precise measure on 5 blade aperture openings but a close measurement at lens/opening center can. _________________ The best camera ever made is the one that YOU enjoy using and produces the image quality that satifies YOU. |
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