1. When changing to a different type of sandpaper, the polishing direction should be changed by 45°~90°, so that the stripe shadow left by the previous type of sandpaper can be distinguished. Before changing to a different type of sandpaper, the polishing surface must be carefully wiped with a cleaning solution such as 100% pure cotton and alcohol, because a small piece of sand left on the surface will ruin the entire subsequent polishing work. This cleaning process is also important when switching from sandpaper polishing to diamond polishing paste polishing. All particles and kerosene must be completely cleaned before polishing continues.
2. In order to avoid scratching and burning the workpiece surface, special care must be taken when polishing with #1200 and #1500 sandpaper polishing materials. Therefore, it is necessary to load a light load and use a two-step polishing method to polish the surface. When polishing with each type of sandpaper, polishing should be performed twice in two different directions, rotating 45°~90° each time between the two directions.
3. Polishing with sandpaper requires the use of soft wooden or bamboo sticks. When polishing a round or spherical surface, using a soft wooden stick can better match the curvature of the round and spherical surface. Harder wood sticks, such as cherry wood, are more suitable for polishing flat surfaces. Trim the end of the wooden stick so that it matches the shape of the steel surface, so as to avoid the sharp angle of the wooden stick (or bamboo stick) contacting the steel surface and causing deep scratches.
