Use the Scotch Brite scrubbing pad to gently buff the surface (Scotch Brite is a popular brand of of plastic scrubbing pad meant to emulate steel ... Ferric Chloride is another common etching ...

He’s come up with a way of creating PCBs with any 3D printer and steel rod ... is using the traditional method of etching away copper, just some ferric chloride and a bit of time.

ferric chloride, 2 ml. concentrated hydrochloric ... These observations were made upon a carburized plain carbon steel, upon a carburized ‘Westinghouse Puron’ iron (spectrographically pure ...