I lay out the desired pattern of lines on paper and tape the GG with the ground side up on the paper. A needle held in a pin vise works well as a tool. A straight edge with tape applied to the bottom to protect the GG ensures straight lines. These lines appear fine and bright against the image, much better than the printed lines on some cameras.Originally Posted by GMOG
I like the sound of this. I could practice making the lines on some scrap glass I've got laying around, to test pressure, how consistent the line is, etc. I have to consider the "permanent" side of this option carefully. I do, however, have an extra GG assembly so if I screw up I've got back up. Thanks for the suggestion.
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Greg
Thanks for the reply, Steve. I also found useful information regarding proper setup of the gg and fresnel at Graflex.org. But what I read there differs from your suggestion of placing the fresnel with the grooves towards the lens. Does what you suggest minimize the appearance of the ridges at the tops of the grooves, by placing them farther away from the ground surface? That's what I'm seeing, those sharp edges that are right up against the gg.
My little test of the gg without fresnel was just to see if it was even worth figuring how to shim the gg without the fresnel in place. I determined it wasn't worth the effort due to how dark the image was in the corners.
I like the idea of marking out lines with a drafting pencil. The impermanence of this solution is appealing. I will probably try this before actually cutting the glass.
I did wash the glass and fresnel from both Graflexes, following the "warm soapy water soak and gentle finger tip scrub" approach. It made a big difference. Both cameras came to me in filthy condition, the '53 especially. It looked like it had been opened up and put on a shelf for display and left for years. Dust. Aged, greasy finger prints. Cig smoke grime. It was gross. The bellows were degraded and had to be replaced, too. It surprised me when it cleaned up so well.
Last edited by GMOG; 14-May-2019 at 18:36. Reason: Spelling error
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Greg
The fresnel position is what I remember for several cameras, but check it out, in case my brain went bad... But I seem to remember that Graphic fresnels are often scuffed on the grooved side, so that would be the exposed surface where it can be dinged by film holders etc while inserting or off the camera... Double check and report back...
The fresnel is a lens, and needs to be orientated correctly or focus error time... Just shimming the gg without the fresnel is not the same space as the thickness of the fresnel (on the Pacemaker) will cause an error as the fresnel is an optical element with a different FL than a flat... Check this, but I think the spacing without fresnel for gg over Graflok focus panel is about .047"... You can get brass or wood strip this thickness from a good hobby shop, and put in the corner areas...
Pencil works fine on rough side of gg but can smear, so don't touch it, and it's on the inside so no problem for spring backs... A pencil like a 3H or 6H will leave it's mark...
Try it!!!
Steve K
I made some time today to photograph the tools I used for this project. I'll do my best to describe how they were used, and also to clarify further for anyone wanting more detail.
I'll start with the forward tilt modification. After removing the front standard from the camera and removing the tilt set screws and stops, the first step was to scribe the radii that mark the upper and lower edges of the holes using a drafting radius template and steel scribe:
I got lucky with that radius template having a groove that matched the radii I needed to scribe. A compass with steel points would have worked, too. And, I used a standard caliper to measure the distance from the edges of the existing holes to the outer edge of the frame, and then to scribe that mark into the other side for reference. Here's a photo from post #1 that shows the lines scribed along the radii, original holes on the left:
For cutting the holes I started by marking center in more or less the middle of where my new holes would be located. I drilled in three stages, ending with a 1/8" bit which was just under the total width needed. The 1/8" drill bit left a hole just large enough for me to insert the small, fluted carbide cutter with which I finished roughing out the oblong hole. These tools were mounted in my flex shaft but a Dremel would work, too.
To finish the holes I used files. I used 2 three square (3-sided) files and 2 half round (flat on one side, rounded on the other) files. I used diamond files to get close (the red handles), and traditional steel files to do the final work since they make sharper corners and leave a nicer finish. It comes down to removing a little material, trial fitting the set screw to check fit, filing off a little more material, etc., until the screws fit in the oblong, keyed holes.
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Greg
I flipped the front standard on mine. That is a great mod though. I probably would have done that instead.
If you want to brighten your ground glass you can put a little wax on it.
Now I'll show what I used for the swing mod.
Everything starts with marking off lines for reference, and to mark the rail clamps on the bottom side of the standard I used a compass with steel tips.
I centered on the bolt in the middle of the frame, in the screw slot. You can see two sets of scribe lines on the clamps. I decided after marking it off once that I should remove less material rather than more, and so I made another set of lines farther out from center. There was no need to remove more material than that so I'm glad to have made that decision.
To make the rough cuts I used a cut-off wheel (Dremel wheel and arbor), and the ever useful fluted carbide cutter mounted in the flex shaft.
I removed sections of the outer rail before working on the clamps, to make room for the tool.
At this point I thought I might leave a bit of the outer rail guides but trial fittings showed me that it wouldn't allow for enough swing so I decided to remove the outer rail guides completely. It's OK because the clamps do a fine job of keeping the standard centered on the bed.
I've bumped up against the image limit so I will continue in the next post.
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Greg
And to finish the work on the standard clamps and rail guide removal I used files, flat files this time. The top file is a #4, the middle one a diamond file with fairly heavy grit, and a #2. The #2 file has a coarser cut and was used first. The diamond file was used to target the high spots accurately. And the #4 was used to make the final cuts along the entire surface.
Not perfect but good enough.
And a general tip in relation to file maintenance is to use fine brass brushes to keep cuttings from clogging up the teeth. I stop every few passes to brush the file off. The result is much faster work that offers better tactile feedback, and files that remain useful for a long time. If you ever get pieces stuck in the teeth that brushes will not remove use a piece of brass with a pointed edge to pick the pieces out.
That top brush looks pretty bad but it works very well for scrubbing off larger files. The small brush is for the smaller files. I've been using both for more than 20 years now.
Thanks for reading!
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Greg
why not slot the whole radius on the front standard for continuous tilt?
Thanks for the question/comment. I might do it. Having freedom to place the set screws in different positions might make it easier to get my fingers on the nuts when using wider lenses, when the standard is back between the supports that come down from the box to the bed. As it is now, when I mount the 90mm Fujinon, the nuts can be a little tough to rotate, especially if I left them a little too tight.
Last edited by GMOG; 28-May-2019 at 17:16.
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Greg
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