Just take your time and don't F it up. Remove a little at a time and you'll do fine. Filing/sanding is easy. I can nearly assure you that it's faster than trying to FIND a FF holder. Heck, even if you DO F it up (you WON'T) then just buy another standard carrier.
If you are not especially technically demanding, you might play around with a 645 carrier. If you tape the negative to the carrier then flatness is less of an issue. I've used a 6x9 carrier to print two 35mm frames (with sprockets) on the same print.
There are some good ideas floating about in this thread by well-intended posters. However... NOTHING will hold your film flatter or better aligned than an original carrier even if modified "slightly" to fit your needs. Cardboard, tape, etc., all okay... but they FLEX at least a little bit. I've tried those methods and they do work but flatness/alignment are ALWAYS better with carriers made to precisely fit your image.
Just be careful filing. It will scratch your negative even if it looks really smooth. So have some old junk film that you can test first by rubbing it around, and go at it again with the superfine sandpaper.
Just be careful filing. It will scratch your negative even if it looks really smooth. So have some old junk film that you can test first by rubbing it around, and go at it again with the superfine sandpaper.
Yes, exactly correct. This is the reason for follow-up with increasingly finer sandpaper 360 through 1000 grit especially on the edge that meets the film. Final sanding is with a very light touch. Then paint the edges flat black.
I'm gonna go for it DIY. I can't imagine 2 mm is gonna make any difference in the ability to hold my film flat and I think it's absurd to spend even $50 for two pieces of metal (yes, that is oversimplistic).