Whether you'd like to restore your family's favorite skillet or fix up a garage sale find, removing surface rust from a durable, dependable cast-iron pan is a breeze. As long as the rust isn't too serious--no deeper than 1/8 inch (3 mm)--you should be able to return the pan to cooking shape. After removing all the rust, be sure to season the pan before using or storing it.
Depending on the pan's size, pour 2 to 4 tbsp. salt into the middle of the pan. Add an equal amount of vegetable oil.
Scrub the pan vigorously with a folded paper towel, concentrating on the rusted spots but covering all surfaces with the oil and salt mixture. Add more salt or oil as needed.
For more serious rust spots, scrub with fine steel wool.
Wash the pan with dishwashing liquid and rinse well with hot water. Dry completely.
Seasoning the pan
A well-seasoned cast-iron pan will resist rust and create a virtually nonstick surface for cooking. To season it, brush vegetable oil lightly over all its surfaces.
Heat the pan in an oven at 250°F (120°C) for 1 hour, recoating it with more oil after 30 minutes.
Wipe the pan well with paper towels, and let it cool completely before using it.
To preserve this natural, protective coating, do not use soap when cleaning a seasoned pan. Instead, scrub it with salt and oil, rinse it with hot water, then dry it completely over low heat before storing it.
For quick removal of rust spots, use a hand drill with a wire brush attachment. Take care not to scrape away too much metal; hollows in the pan will lead to uneven cooking and food scorching.
Spun-steel and carbon-steel woks benefit from the same care as cast-iron pans.