Moisten a cotton cloth with a few drops of mild dish detergent. Wipe the brass hinges with the cloth to remove surface dirt and debris.
Remove protective coating. Work in a well-ventilated area and protect your work surface. Apply lacquer thinner to each hinge according to the manufacturer's directions. Allow thinner to remain on the surface of the hinges for the recommended amount of time. Gently remove loosened coating by brushing the toothbrush along the direction of the grain.
Rinse hinges in a mixture of water and mild soap. Dry thoroughly with a clean cloth. Do not allow brass to air dry as this may cause hard water stains.
Put on your gloves and gently polish and buff each hinge with a clean cloth.
Apply a lacquer finish to each hinge to deter future corrosion.