Cut marks from the wheel are best removed with a scraper. Avery sells a dandy tool for this purpose. Alternately, a woodworking scraper can be used if you need one right away - ususally found in high quality woodworking tool store if you have one in your area. I've never looked for one in the orange box store but it's not likely they stock these.
Obviously with caution and a bit more care required when using is a simple single edged razor blade but BE CAREFUL! This is best done with the blade mounted in a holder of some kind.
Regardless of which approach you take, you'll have a VERY smooth edge with just a few strokes. If using a straight scraping tool, you'll need to dress the corners with 400 grit - wet progressing to 600, 1000 and whatever you have the patience for. The Avery tool provides a radiused edge which you would probably find the most acceptable, still requiring final finishing with the wet 400, 600.... Final polish with some white rubbing compound if you want a clear, smooth edge.
All this takes less time than it took to write about it.
Best of Luck
Carl Raichle
RV-9A, N194CR
Weight and Balance tomorrow - Inspection soon!