Mold polishing usually uses oil stone strips, wool wheels, sandpaper, etc., so that surface of material is plastically deformed and convex portion of workpiece surface is removed to obtain a smooth surface, which is generally performed by hand. Method of super-fine grinding and polishing is required for high surface quality. Super-fine grinding and polishing is made of a special grinding tool. In polishing liquid containing abrasive, it is pressed against machined surface to perform high-speed rotary motion. Polishing can achieve a surface roughness of Ra0.008 μm.
1) Common tools for mold polishing include: sandpaper, oilstone, felt wheel, abrasive paste, alloy trowel, diamond grinding needle, bamboo, fiber whetstone, round rotary grinding machine.
2) Sandpaper: 150#, 180#, 320#, 400#, 600#, 800#, 1 000#, 1 200#, 1 500#;
3) Oil stone: 120#, 220#, 400#, 600#;
4) Felt wheel: cylindrical, rounded, square tip;
5) Grinding paste: 1# (white) 3# (yellow) 6# (orange) 9# (green) 15# (blue) 25# (brown) 35# (red) 60# (purple);
6) Sickles: square, round, flat, triangular and other shapes;
7) Diamond grinding needle: generally 3/32 shank or 1/8 shank, with round shape, cylindrical shape, long straight column shape and long round cone shape;
8) Bamboo: Each shape is suitable for operator and shape of mold. Function is to press sandpaper and grind it on workpiece to achieve required surface roughness.
9) Fiber whetstone: 200# (black) 400# (blue) 600# (white) 800# (red)