
Posted: Sun Nov 22, 2020 8:30 pm
Lens are rarely their marked (nominal) focal length. They can be up to 3mm either side of nominal. The cam list is
https://www.graflex.org/speed-graphic/top-rangefinder-cams.html . There are 5 cams/focal lengths for 135mm lens, 6 if you count the 138.7mm P32.
Graflex Graphic cameras made from 1912 to 1946 had the infinity stops set with the yoke fully retracted. Starting with the Pacemaker series in 1947 onward the yoke is to be run forward .040 inch ±.010 inch then the focus lock set. The front standard is then moved forward until an infinity target at least 5000 feet away is critically sharp on the ground glass with the front standard square to the yoke. Slide the infinity stops against the front standard, tighten the front screws then move the front standard back and tighten the rear screws. A 1.8mm /,07 inch wide slot screwdriver just fits the infinity stop screw heads.
With a calibration cam installed in the rangefinder adjust the rangefinder to show infinity at the same yoke position.
The Graphic Top Rangefinder service instructions gives the full procedure:
http://www.southbristolviews.com/pics/Graphic/manual-pdf/TRFService.pdf
The full Top Rangefinder Service Manual is available here:
http://www.southbristolviews.com/pics/Graphic/manual-pdf/servicemanual.pdf