Su said the main group . Moistened with water on the line , in order to take away the debris worn sandpaper roll  is mainly used to deal with the outlet of the first but not the model used pliers to cut down the model , and then use a pen knife to Xiaoduan connections , but do not directly removed, will stay under the ugly outlet . Then when sanding parts of the model will be based on the best sandpaper fixed on different objects , for example, you do not polish a large area of ​​particular parts of the ground, to find a small bottle, put sandpaper glued to the upper perimeter with partial arc face sanding . Usually first with 800 , polished smooth and then polished with a fine 1200 . Found that outlet is gone but the entire surface of the model is not smooth polished plastic is how to do ? Recommended to buy polishing paste , coarse purpose on the line, after spotting grinding polishing paste definitely handy. Coloring on random , and polished smooth no outlet on the line . The water sandpaper with scissors into a an appropriate size , then moistened with water , then polishing , is to reduce scratches, in fact, not cleaning the bathroom is also no problem , because you then have to fill soil . If the hormone group had to be wet , sanding paper after a good clean , observe and then decide not to continue grinding .