Cast iron provides a number of advantages for culinary use. It cooks very evenly and retains and conducts heat well. However, cast iron does have a tendency to rust. To prevent cast iron rust, keep your skillet well-seasoned and don't expose it to water for long periods of time. As noted by Lodge Cast Iron, if rust is severe, you may have to have the skillet sandblasted and re-seasoned. Normally, however, it is easiest to simply scrub the rust off the skillet and re-season it yourself.
Things You'll Need
Steel wool or other abrasive scrub pad
Dry the skillet completely with the kitchen towel.
Pour some vegetable oil onto the towel and rub it onto affected areas. If rust does not disappear, continue to Step 3.
Scrub the skillet with plain warm water and a steel wool or abrasive scrub pad. Continue to scrub until all the rust has been removed.
Dry the skillet thoroughly.
Re-season the skillet. Rub vegetable oil on the inside and outside with the kitchen towel.
Place skillet in a 400-degree F oven, upside down and with a sheet of aluminum foil on the rack below it, and leave it there for at least an hour.
Turn the oven off and allow skillet to cool completely.
Remove the skillet from the oven and store in a dry place.
Do not use harsh chemicals or soap to clean your cast iron skillet, since this will remove the seasoning.