First of all, the order of polishing, as follows: 800 mesh-1000 mesh-1200 mesh-1500 mesh-2000 mesh-coarse mesh polishing paste-fine mesh polishing paste-extremely fine mesh polishing paste, the beginning of the 800 mesh is not absolute, depending on the roughness of the surface of your stuff had, if you come up to the first thwarted sanding, I'm afraid that you have to take the 200 mesh-400 mesh and then take the 800 mesh, because thwarted polishing Finish too rough. In short, a principle, the lower the number of mesh after the more rough, but hit down more, hit with more energy, if you come up with 2000 mesh to hit at all. Above said sandpaper are water sandpaper, because I do modeling, do not know how you want to play the plastic material, although called water sandpaper, but sanding does not need to be wet. Sanding cream with a cotton swab dipped in sanding on the line, drawing a circular arc of the grinding, here to remind you of a point, the concentration of very fine grinding ingredients is very high, do not touch your hands when sanding, or it will peel. This mesh sandpaper will be sanding all the way to the place, you can change the finer purpose, this time to replace the timing of their own look to come.
Now to give you this thing you specifically how to play, each side of the rectangle can be used to sanders (that is, a handle), in the bottom of the sandpaper fixed sandpaper, so that there is a flat surface, directly sanding on the line, hit the time to look at the point, don't hit the surface of the diagonal, with the sanding block is also OK. The four corners are more troublesome, even with a sander can not guarantee that the arc of the same round, the method is similar to the above, but do not a plane, you can use what I said above to find a round stick, with a curved surface bit by bit grinding, or cut the sandpaper into a long strip, pinch the ends, the bend will also produce a round arc. , Be sure to hit the curved stuff with a curved surface as well. Compare the four corners when you hit it, it's about right. Do you want to polish the eyeglass lenses? I think in this case is not to go to the optical store to find turn professional to grind better.