The drum of most dryers is covered with enamel appliance paint to protect it from rust and stains. However, if the enamel paint is chipped, the underlying metal may rust with exposure to moisture from wet clothing. To prevent damage to the paint, turn garments with heavy zippers or snaps inside out. Repaint any chipped areas with enamel appliance paint, which is available at appliance and hardware stores. To remove rust, use vinegar because the acid in it breaks down rust, as well as hard water spots.
Pour enough vinegar onto a paper towel or clean cloth to moisten it. Lay the paper towel over the rust marks in the dryer and wait 10 minutes. Vinegar is an acid that effectively cuts through rust on many surfaces, including the interior of the dryer.
Moisten a paper towel with clean water and wipe off the vinegar. Dry it with another paper towel or clean cloth.
Rub any remaining rust on the dryer drum lightly with steel wool to remove it. Wipe again with a damp cloth.
To clean the drum of the dryer, mix a paste of powdered washing powder and warm water. Apply the paste to stained areas and rub gently, according to Whirlpool. Don't use flammable solvents or cleaners inside a dryer.