modified Dahle paper trimmer
I used to set up a rather elaborate system of fences, squares and clamps to cut 5×12 film down from larger stock, but if this move to 4×10 is to be sustained I realized I’d need something a little easier to setup. A length of aluminum angle, two 8/32 threaded knobs, an 8/32 tap and minutes later I have a 25-sheet box of 8×10 film cut perfectly down the middle. I did use some plain paper cut to the exact dimensions of 8×10 film for laying out the fence location to make sure it was cutting exactly down the middle before tapping the cutter table. It’s much easier to register against only one fence- only need to go for parallel with a single cut, square will take care of itself, so I use a fence longer than the film, and don’t even try to register against the squaring fence. Also, practicing in the dark on plain paper first eases anxiety by orders of magnitude. I use a piece of paper as backing to protect from scratches. Also, slipping this paper forward under the pressure bar between each cut gives a little ramp to guide the new sheet of film under the bar to minimize fumbling in the dark. This is removed before the cut is made then reinserted to load the next sheet(s). Also, a ‘pan’ is made out of a sheet of paper with perpendicular folded edges to catch the cut half, making it easier to pick up the film from the table and slide the film into your hand. Lastly, I use a plastic shim along side the squaring arm- pushing this under the pressure bar lifts it to let the film slide under more easily and without scratching, and leaves both hands free to guide the film. The over-sized knobs make the guide easy to setup and remove. The nylon spacers raise the knobs above the angle letting them turn freely.
I’ve hard good luck cutting up to 4 sheets at once, but ganging film together does tend to make the sheets stick together more after cutting which does make separating the sheets for loading slightly more tedious. (Also, I don’t re-notch the film, so during loading I sometimes have to count further into the stack to find a sheet with ‘confirmation’ notch to reassure myself the emulsion side is correctly oriented. Always keeping the film facing up before and after cutting saves the chore of recoding, but to be safe I do notch the cardboard folder the film is stored into to mimic the orientation of the film within. )The time saved during cutting, along with fewer surfaces exposed to the risk of scratching and dust, seems a reasonable trade off. I don’t count the sheets, just sort of bend the corner of the stack to release several sheets, as with a deck of cards.
OK, so it’s not completely automatic, but much better than previous riggings. And the above does sound much more complicated than it actually is.
