Chrome is short for chromium, a naturally occurring element electroplated on the surface of hard metal to give it a fabulous shine. Chrome is a soft metal that resists tarnishing, but over time, exposure to air and the elements will cause it to rust and pit. If not taken care of, pitted chrome will continue to deteriorate. You can polish out minor pitting by hand, but deep pitting requires professional replating.
Wash the part with water and dish detergent. Rinse the part and dry it with a lint-free cloth. Run your fingernail over the pitted section. If the pitting does not catch your fingernail, you can polish the section with steel wool. If the pitting catches your fingernail, it is too deep for polishing and needs professional restoration.
Dip a piece of 0000 fine steel wool into water and lightly polish the pitted section. Rub in a circular pattern until the pitting is gone. Wipe the surface with a dampened cloth to remove any steel wool fibres.
Dip a piece of 00000 superfine steel wool into water for a final polish of the surface. Rub in a circular pattern. Wipe the surface with a dampened cloth to remove any steel wool fibres, then pat dry.
Use a cotton cloth and any kind of chrome polish to remove fine scratches and give the part a lustrous shine. Apply the chrome polish to the surface of the entire part.
Spray a light coat of clear lacquer, acrylic or urethane on the part to protect the chrome from oxidation. Follow the directions on the spray can, then apply two to three coats.
Do not polish chrome-plated plastic. The chrome plating on plastic is very thin and you will cause more damage to the surface.