Polishing with sandpaper requires the use of soft wooden or bamboo sticks. When polishing a circular or spherical surface, use a cork stick to better match the curvature of the circular and spherical surfaces. A harder wood, like cherry, is more suitable for polishing flat surfaces. Trimming the ends of the wooden strips so that they can match the shape of the steel surface, so as to avoid the sharp angle of the wooden strips (or bamboo strips) contacting the steel surface and causing deep scratches.
When using different types of sandpaper, the polishing direction should be changed from 45° to 90°, so that the streak shadows left by the previous type of sandpaper can be distinguished. Before changing different types of sandpaper, the polished surface must be carefully wiped with 100% pure cotton dipped in a cleaning solution such as alcohol, because a small grit left on the surface will destroy the entire subsequent polishing work. This cleaning process is just as important when switching from sandpaper to diamond paste polishing. All particles and kerosene must be completely cleaned before polishing can proceed.
