well, i've been painting my interior, and it looks tight. however, when i leave it to dry, and come back, the parts have a rough feel to them. so, after letting them dry for about one whole day, i went and wet sanded one of the parts from the door. i used 1000 grit. it stripped a little bit of the paint though. nothing drastic, and you can only notice a little in not so obvious places. did i use too rough a grit? should i use 1500 grit, or just let the pieces dry some more and then wet sand them. fyi, i cleaned the surfaces REALLY good before i started to paint, with sem stuff: sem soap, plastic prep, vinyl prep, sand-free.
