Selection of mold steel?
There are usually two reasons for the steel grain phenomenon in the mold: one is the problem of the mold steel itself, many mold makers choose poor quality (cheap) steel to make the mold in order to save cost, resulting in the surface of the mold after the mold polishing to appear grain, and some fine lines. At the same time, under the light will lead to distortion of the light, mold polishing can only reduce the phenomenon of mold steel grain. Secondly, the skill of the mold polisher is not good.
