Take a sheet of warm, shiny copper. File the edges, first with a coarse file, then two successively finer ones to make a gently bevelled edge. Smooth the corners so they are slightly rounded. Flip the sheet over and gently remove the burr around the back edge with the finest file.
Then take the copper sheet to the sink and spritz it with soy sauce. Dip a sponge into French chalk and rub it all over the sheet, working the soy and chalk into a paste, making circular patterns in gentle salmon pink until the plate is completely degreased. This afternoon at Swansea Print Workshop.
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Soy sauce?!
Oh yes, excellent for degreasing and not toxic, unless you’re allergic to soy of course