Clean the surface of your Americast sink to remove any dirt and grit that can further scratch the porcelain coating. Moisten a clean cloth with water, add 1 drop of dishwashing detergent to the cloth and use the soapy fabric to scrub the sink's surface.
Rinse the sink's surface with a clean, damp cloth.
Place a pumice stone into a bowl and fill the bowl with water. Allow the pumice stone to remain in the water for one hour to ensure it is fully wet, turning the pumice stone over halfway through the process.
Wet the surface of your Americast sink at the site of the scratch and rub the wet pumice stone over the scratch to remove it and smooth the sink's surface. For the best results, move the stone in the direction of the scratch. For example, if the scratch is horizontal, rub the pumice stone horizontally with the scratch; if the scratch is vertical, rub the pumice up and down with the scratch. Continue applying the pumice stone until the sink's surface is visibly smooth and smooth to the touch.
Wipe the sink's surface with a damp cloth to remove the pumice stone residue.
Sprinkle baking soda onto the damp cloth and scour your Americast sink with the nonabrasive baking soda. Rinse the sink with water and dry it with another cloth.