The good news are that sheaths adapt film to plate, so they are not holder specific. Unless you run into some superficially sheath like film or plate holder for a "detective" camera or magazine (which would not be your damage if you bought them at sheath value, they tend to sell at higher prices), any will do. Provided that the film and plate size are right, that is - there have been 6.5x9 to 9x12 and 9x12 to 10x15 adapter sheaths that might be advertised only by their 9x12 dimension.
I've been very fortunate in that about 50% of my 9x12 plate holders (of all kinds) came with sheaths as a surprise. I did manage to find someone selling a large number of sheaths all by themselves a few years ago, but I paid about $5 each for them. I'm glad I did as 9x12 sheaths seem to be harder to find these days, if my recent Eb@y searches are any indication.
I shoot a 6.5x9 Recomar, and am always looking for sheaths. I think I could make them pretty easily out of thin aluminum flashing, but have not found any here yet. I have made them out of card, but they don't work very well.
One thing about the sheaths, they hold the film the thickness of the metal behind the ground glass plane (assuming registration is perfect). I've never noticed an effect, but tend to shoot the tessar stopped down as much as possible.
Last edited by Sevo; 31-May-2012 at 04:51.
That should work. Now that I think about it, aluminum cans might work as well. Perhaps I'll give it a try, and if it works I can post it on the DIY.