scuffing monokote may make the inks adhere a little better but more likely the ink will bleed into all the little crevases sandpaper would create. not much but the best part of and inkjet printer is the crisp clear edges it gives. i also have a hp3500cp 48" printer. you all keep referring to inkjets as plotters but that is actually wrong. a plotter cuts vinyl. a printer prints inks on vinyl. without going to a 25,000.00 machine they don't do both.