you can buy a set of hollow punches for less than $15. I bought one years ago when I needed to make sizes of a pad not offered by the manufacturer. I made 2" pads (meguiar's polishing pad). the only thing is they may not come out perfectly round (every time) depending on how you strike (i use a...
if you do another few passes and there isn't an improvement, try stepping up to a light cutting pad and re-check your results. here are a few examples on arm speed...