Depends on the scratch if its what you would consider a fine scratch 2000 then 3000 and that will buff it back to new.....if its a deep scratch you will be wasting your time with the 2000 and will need to drop it down to 1300-1500 for a few weeks of just general buffing once or twice a week and before you know it ...it will be gone then step it up to the 2000 then the 3000 to finish it off.....I just wrap my magnet with a waterproof paper....stop by Jorge I have the paper....this is the beauty of acrylic just think if you would have done that in glass it would have been permanent