Dropping something heaving into your steel or cast-iron sink can cause a noticeable chip or dent in the enamel surface. If you cannot replace the sink entirely, consider repairing the enamel yourself. Epoxy filler is available in the adhesive area of your local hardware store. Epoxy allows you to conceal the chip by painting with a substance designed specifically for enamel. In just a few hours your sink can look as good as new.
Clean the area around the chip thoroughly with soap and water.
Sand the chip with 400- to 600-grit wet/dry sandpaper. Sanding roughens the surface so the epoxy filler can easily adhere to it. Clean all sanding dust and debris with a damp cloth and let the surface completely dry.
Mix the epoxy filler per the manufacturer's instructions. Typically, epoxy kits consist of two ingredients--the hardener and catalyst, which are mixed together to create a paint-like substance.
Apply the epoxy to the chip with a small paintbrush. Work slowly and carefully to smooth the epoxy and blend it in with the existing enamel. If you need multiple coats, wait until the first coat dries completely before adding the next coat. Consult the product's instructions to find out how long the product takes to dry.
Wait 24 hours before returning the sink to regular use. Do not clean the newly patched area for at least a week so the epoxy can cure.