so i stained my box today, i think its birch or maple, not sure. it went good and after that dried i applied 3 coats of polyurethane gloss to finish it up with a little more than an hour drying time between them. now to my question. i plan to do another coat of gloss tomorrow but can i sand it lightly with high grit sandpaper to get a smooth glossy finish or will that mess with the stain or gloss? im trying to get a piano like gloss finish or close to it. thanks.