When I want a real smooth finish instead of using steel wool and having all the steel dust to contend with I take a single edge razor blade and “plane” the fulling cured Poly coat with it. Even though it has a small work surface it doesn’t take long, even on a large project, to go over it and remove all the little dust bumps. Pushing the blade is the best way but if you have trouble digging in then scrape with it instead.
-Jim Elliott
