Dan,

Many thanks for all this very valuable information.

I modified such a back, it wasn't overly difficult, especially if you aren't looking for a great degree of neatness. A Dremel will do you.

2x3 Graphic vs Graflex roll film back by Nesster, on Flickr

Basically, I ground down the second ridge, and added a groove. It took a couple of tries to get the groove just right.

Here's a website that has some instructions
http://www.bnphoto.org/bnphoto/LFN/XLBackConv1c.htm

Many thanks for the information. I have decided that since I already have a very nice condition and fully working 6 x 7 cm RH-10 Graflok back for my 2 x 3 Century, I will just wait to get the proper and equally nice condition RH-8, as and when one becomes available. Someone else very kindly sent me screeds of information and instructions on converting the Horseman 6 x 9 backs to make them Graflok compatible but as the very last sentence said: “ of course it is a touch prone to light leaks in bright sunlight.”

Wilson

A metalwork acquaintance modified a Graflok holder to fit my 2x3 Crown with Graflex back, just as in Nesster's post above. It works very well, focus is OK.

Graflex cameras were laid out with an engineers rule, all measurements are in inches, tenths, hundredths, thousands.

Film holder measurements same for 2 sided film holder, plate holder, bag magazine, grafmatic, and roll film holder in 2x3 format
Inside edge of groove to outside edge of holder 4.343 inches.
Groove width .050 inches.
Grove depth .035 inches.
Photo with measurements in this private Flickr album
https://www.flickr.com/gp/thirteenthumbs/0714bF

edited 2/15/2018