Manufacturers bake porcelain enamel onto metal to create a hard, protective barrier that looks attractive and is easy to clean. However, porcelain enamel is a type of super-heated glass, and it can chip if struck with a hard object, exposing the metal underneath. If moisture contacts the metal, rust can begin to form. Dripping faucets or other types of constant water contact also create rust stains on the surface of the enamel. Homeowners can remove the rust and repair the enamel to restore fixtures to their former glory.
Pour a small mound of salt into a bowl. Drip lemon juice into the salt and mix the two with a spoon. Continue adding lemon juice and mixing until the salt and juice form a paste.
Apply the paste to any rusted stains or rusted metal exposed by chipping porcelain. Wipe the paste on with the spoon you used to mix it.
Allow the mixture to sit overnight, then wash it off with a damp cloth. The rust should be gone.
Sand down the edges of any chipped porcelain with an emory cloth.
Mix porcelain repair compound with a high-gloss, alkyd-based paint matched to the color of the enamel. Create another batch if the mixture ends up differing in color from the porcelain, using less repair compound.
Apply the compound to the chipped porcelain. Scoop up some compound on the edge of a razor blade, fill in the hole, then use the blade to smooth the compound to match the contour of the enamel.
Allow the compound to dry. Remove any dried excess compound using a cotton swab soaked in fingernail polish.