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henseman
14-Aug-2012, 20:11
Looking for some help/advice on converting a B & J 5x7 w/4x5 reducing back spring back, to a graflok back. What is the possibility and the problems I'll face in the endeavour?

Also, I want to mount a Schneider Symmar 240/420 convertible lens w/Compur shutter onto a Cambo SC2. Can anyone tell me what cambo lensboard I would need to accomplish this...ie hole size?

Thanks in advance,
Brian

Ivan J. Eberle
14-Aug-2012, 21:00
Essentially a Graflok back is an incremental improvement to a Spring back (not to be cofused with a Graflex back). Major difference being two sprung levers with hooks on the ends which remain attached to the rear half of the back when removed, instead of fixed springs. The hooks each engage a dowel pin within a recessed well. There are locking sliders that engage accessories when the GG back half is removed. If you have a beefy enough spring back base with extra material allowing for machining or building this well,and a place to tap into for the sliders, it may be straightforward. If not you may have to acquire a whole assembly (both halves).
Anyway, it would be best to look at the back half of a Graflok and physically match it up to your existing back-- before buying the pieces. Whole junk Speed Graphics sometimes sell for less than a separate back.

Dan Fromm
15-Aug-2012, 06:30
What machining facilities/skills do you have?

I ask because I have a 4x5 Graflok back from a mug shot camera gathering dust. It is a dividing back, has a septum that will have to be removed. It has a 4x5 Graflok focusing panel that will not accept a focusing hood. And it has the ramps that the Graflok sliders fit on but not the sliders themselves, so would need sliders and springs for them. Its back is flat as can be so it will attach to nearly anything. Attaching it to your reducing back may require drilling holes. Price very negotiable.

Measure the back of the shutter and go here http://www.skgrimes.com/products/new-copal-shutters to find the recommended hole size (diameter, not shutter #) for it.

sully75
15-Aug-2012, 09:17
Are you planning on converting an actual spring back to a graflok back? That would be a lot of work for something you can buy for $40 and fit to your old camera.

henseman
15-Aug-2012, 14:58
Hi....sorry for the confusion....I want to take the old spring back off and replace it with a graflok back. I'm just not sure of the problems I may have doing so. This is a 5x7 B&J Folding View or "Tailboard" camera with a 4x5 reducing back.

Ivan J. Eberle
15-Aug-2012, 16:12
I don't recall how the B+J 5x7 (Rembrandt?) does portrait orientation but the 4x5 Watson Press had a rotating Spring back, which to me is a feature worth preserving. Speed Graphic Graflok back doesn't rotate, only the Supers and Super Speeds had Grafloks that did. Quite a bit less common and a bit oddball. So here's a situation where modifying an existing Spring back might be preferable. (I'm a Meridian owner and I've seen any number of poorly hacked up camera on eBay where someone screwed up the nice revolving Spring back to graft on a Graflok.)

Jim Jones
15-Aug-2012, 18:56
Almost all B&J cameras have reversing backs. The only exception I remember is an ancient press camera. Replacing the spring back with a Graflok back would preserve this reversing feature. It should be an easy project. With basic tools you can make a new back plate to accept your Graflok back, and maybe sell the entire spring back.

BTMarcais
16-Aug-2012, 12:05
The reducing back I had for my BJ had a raised area w/ the ground glass/spring back that was screwed into the frame for the reducing back. I unscrewed this and took off the spring back, and then drilled holes to match the holes on a graflok back from a beater speed graphic, and screwed the graflok back in place. Aside from drilling the holes it took maybe 10 min.

-Brian

tim o'brien
18-Aug-2012, 11:54
The reducing back I had for my BJ had a raised area w/ the ground glass/spring back that was screwed into the frame for the reducing back. I unscrewed this and took off the spring back, and then drilled holes to match the holes on a graflok back from a beater speed graphic, and screwed the graflok back in place. Aside from drilling the holes it took maybe 10 min.

-Brian

Grandma was slow, but then... she was old. *L*

Yep, about ten minutes. Buy the whole graflok back off a junk Speed, unscrew it, screw it in place on the 5x7 reducing back.

tim in san jose

sully75
18-Aug-2012, 20:15
One problem if you are thinking of using Polaroid backs...the pack film back has a lip that goes below (or in front of or whatever) of the edge where the film holder goes. So if you mount a standard graflex back against a wooden back, the polaroid holder is not going to be able to fit flush against the back.

Pretty impossible to explain, but look at a Polaroid back and then think about the nub where you pull on the film...it's not going to fit...unless you route away part of the wood so that it has a little slot to slide in.

tim o'brien
18-Aug-2012, 22:30
One problem if you are thinking of using Polaroid backs...the pack film back has a lip that goes below (or in front of or whatever) of the edge where the film holder goes. So if you mount a standard graflex back against a wooden back, the polaroid holder is not going to be able to fit flush against the back.

Pretty impossible to explain, but look at a Polaroid back and then think about the nub where you pull on the film...it's not going to fit...unless you route away part of the wood so that it has a little slot to slide in.

My wooden adapter is not flat across... it is beveled from the edge of the 4x5 to the edge of the adapter.


tim in san jose

Steve Feldman
30-Mar-2013, 15:34
The reducing back I had for my BJ had a raised area w/ the ground glass/spring back that was screwed into the frame for the reducing back. I unscrewed this and took off the spring back, and then drilled holes to match the holes on a graflok back from a beater speed graphic, and screwed the graflok back in place. Aside from drilling the holes it took maybe 10 min.

-Brian


Hi - A bit off topic and a bit late, but maybe you can help me. I too have a B&J 5x7 w/ the 4x5 spring back. One of the springs is broken. The other spring is sprung. Do you know where to find replacements? Would be very helpful. Thanks. - stevef123@sbcglobal.net