I use a 1/4 sheet pad sander and about 220 grit and then progressively finer grits of emery paper. Finish it off with rouge and a cotton buffing wheel. I can and have made trashed posts look better than new. I figure out how far I will be inserting the post before I start sanding and apply duct tape below that line so that it doesn't get sanded at all. It would fe foolish to sand the part that's not going to show.