This is not a cleaning process (in the sense of "removing dirt"). One way to create PCBs is to use a board with a copper surface, put a protective mask on the l

This is not a cleaning process (in the sense of "removing dirt"). One way to create PCBs is to use a board with a copper surface, put a protective mask on the locations that should have traces or pads and then etch away copper from everwhere (else). In the end, only copper under the protective mask will remain. Etching is faster when the solution is moved around during the process. This machine does exactly that.