Might work for my paper trimmer blades? How to Make Your Rotary Cutter Last Longer Sharpen rotary cutter blade by folding tin foil several times and cutting it with Cutter. Test on fabric scraps until it is sharp.
How to Sharpen Your Rotary Cutter Blade: fold a piece of foil a few times; slice away with blunt/dull rotary cutter, pausing a few times to test it out on fabric scraps till it starts slicing your fabric. end up with an almost new rotary cutter!