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View Full Version : Help needed: cleaning a Super Graphic rangefinder



Thomas Greutmann
4-Apr-2007, 06:39
Hello,
I just got hold of a Super Graphic. Although I will use it mostly with ground glass focusing I would like to put the rangefinder to work. I have already found out how to switch rangefinder cams, the mirrors are in working and reasonably clean, so the rangefinder works in principle.

There is just one small thing which is not working: when I have moved the focus rack inward (focusing towards infinity) the spring is too weak to push the rangefinder mechanism back when I move the focus rack outward. I assume that the mechanism has collected some dirt and needs cleaning and lubricating.

Has anybody done this before? What did you use? Where did you start? Any help is appreciated.

Greetings from Germany,
Thomas

Mark Sampson
4-Apr-2007, 11:47
Welcome to the forum- and take a look at www.graflex.org. You might find some help there.

Paul Ewins
4-Apr-2007, 16:33
Hi Thomas,
I just went through this process last week. It isn't hard but it helps to be methodical.
Firstly, there is a description of the procedure on the Graflex.org site in this thread: http://www.graflex.org/helpboard/viewtopic.php?topic=4011&forum=1

If your rangefinder still has distance scale on the top of the camera you can check that this part is working. Open up the flap inside the camera that covers the rangefinder cam. You'll see a small lever that sits against the top of the cam. By simply sliding the cam side to side you should see the lever move as it runs along the cam profile. At rest, the needle on the distance scale won't be visible. As you move the cam the needle should appear and move all the way across the scale to infinity (and may go past that point). When you let the cam go the internal spring (in the rangefinder tube) should push the cam back again and the needle on the distance scale should swing back past 3 feet out of sight. If it does this then that part of the mechanism should be OK.

The connection between the cam and the metal tongue that sits onto the focussing bed is by a heap of ball bearings and spacers in the thin metal tube. With the cam in place, push the metal tongue back as far as it will go. Again, the needle on the rangefinder should swing all the way around to infinity. When you let it go the tongue should spring back out and the rangefinder needle should drop back out of sight.

If the tongue doesn't spring back immeadiately there are two possibilities. One is that the ball bearings and spacers are gummed up and need to be cleaned. The other is that tongue itself is catching on something. Remove the top of the focussing rail guide so that the tongue is not pressed down and see if it moves freely. If not you can undo the screw holding the end of the rangefinder tube down and gently push it up slightly. Again, see if the tongue now moves back and forth freely.

If none of this works follow the instructions in the Graflex.org thread and remove the rangefinder tube. This can be done without removing the bellows, but it is easier (and reinstallation is a lot easier) if you take out the bellows first. Once you have removed the tube try pushing the tongue back in and see if it springs out again. As before you will need the cam in place for this. If the tongue still won't spring back out properly then you will need to uncrimp the tube and remove the ball bearings and spacers and clean the lot. Follow the Graflex.org instructions carefully.

If the tongue does move freely once the rangefinder tube is removed from the camera it must be binding on some part of the camera or tube when under pressure. The bottom of the tube in my camera where the tongue slid over it was quite rough and I carefully filed it smooth again and lubricated the top and bottom of the tongue with a wax lubricant (bicycle chain lubricant). You don't want to get lubricant inside the tube as this will gum it up. I also checked for smoothness on all the surfaces that the tongue slides over. Finally I reinstalled the tube and checked as I tightened all the screws whether it still worked.

After getting the focussing mechanism on my camera running smoothly I found the distance scale still wasn't working properly. This turned out to be because somebody had moved the metal triangle on the focussing bed that pushes against the end of the tongue. I just set the camera up to infinity from the ground glass, then loosened the screws holding the triangle in place and pushed it back until the rangefinder needle pointed to infinity. This was right at the back of the focussing rail.

Hope some of this helps. As I said at the start it isn't difficult so long as you are methodical.

Thomas Greutmann
5-Apr-2007, 00:48
Paul: thanks a lot, that was the kind of information I was looking for. I will give it a try.

danno@cnwl.igs
18-Apr-2007, 07:50
Try the following link, it should give you a bit of information.




http://www.southbristolviews.com/pics/Graphic/manual-pdf/TRFService.pdf

Dan