There will be a layer of protective film on the newly bought metal sandwich board, which is pasted by the manufacturer before it is sold to users. The purpose is to protect the board and prevent it from being bumped during transportation. After buying the board, you need to tear off the protective film in order to put it into use. There are some things to pay attention to when removing the protective film:
When tearing off the protective film on the surface of the board, pay attention to using even force, slowly tear off the protective film, and then wipe off the residue on the surface of the carved board with a clean and soft towel.
It is strictly forbidden to use tools whose hardness exceeds the board surface to remove pollutants on the board surface to prevent damage to the metal sandwich board.