If the alloy electroplating layer in the welding head has good tinning and corrosion resistance, it is generally not allowed to be polished and filed, which will destroy the original advantages and shorten the service life. If the common copper head can't be burnt into tin (oxide) over temperature, the coating has been damaged, the process needs to trim the shape of the welding head or the copper head has been dented and deformed by "tin corrosion", it is necessary to use file shaping, fine sandpaper or blade to remove the oxide layer as appropriate. We all know that the smoother the metal surface, the more corrosion resistant it is. The polishing of fine sandpaper not only enables the tool to process the edge surface more finely, but also improves its oxidation resistance and corrosion resistance.