Which cleaning method is best for removing smeared metal from a previously machined soft metal part?

Etching is a suitable method for removing smeared metal from previously machined soft metal parts because it relies on a chemical reaction that can effectively dissolve or alter the metal surface without damaging the underlying material. This method is often used in metalworking and manufacturing processes to clean surfaces and prepare them for further treatment or finishing. It can remove contaminants and residues that are bonded to the surface at a microscopic level more effectively than physical methods would.

This process typically involves applying an acidic solution that reacts with the metal, specifically targeting the oxides and smeared material without impacting the integrity of the part itself. Because etched surfaces can often be refined further, this method is preferred for achieving a clean, uniform finish, particularly in delicate parts made from soft metals.

Other cleaning methods like mechanical scraping can risk gouging or altering the surface finish, and wiping with solvent, while useful for certain residues, may not effectively remove deeper or more stubborn metallic smears. Acid cleaning generally involves harsher chemicals that can etch or corrode the surface, which might not be desirable in all situations.