I just bought a roll of Entrada Rag Natural, which I love. But I'm having trouble printing on both sides of the paper due to the curl (when printing on the back, the curled edges catch and get jammed). I've tried flattening with a press but even that isn't working. I'm printing something quite long, so I can't use sheets either.

Any suggestions?

This is a difficult question to answer, as different printers act in ways that aren't consistent. I have tried using a D-Roller, which removes some, if not all, of the curl in a roll. The challenge is that you will need to remove paper from the roll and then roll it back onto the spindle, I suspect.