About the edges...I used sand paper for years (80 grit, 120 grit....I tried them all). After the first few swipes the sandpaper is already dead. Recently started using a file and it has been a game changer---much faster and the file doesn't wear out. On the side that will receive the print, I'll lastly run over it with 220 grit paper to create a wonderfully smooth edge for trimming the bleed.