This article was shared by Mom's Pantry friend Julie Miklas, who owned a retail outlet for cast iron cookware. We appreciate her sharing her expertise with us.
A RUSTY OVEN?
I've tried two different methods for removing rust from cast iron and both have worked well. The method you choose will depend on the amount of rust and where it is located.
If you have a small amount of light rust, gently rub it with a dry SOS pad. The rust should easily come off.
The other method is to soak the rusted area in cola. Depending on how rusty the oven is will depend on how long you will need to leave the cola on the rusty spot. If you have an issue with the outside of an oven you can use a sponge to apply the cola, or place the cast iron in a large bowl or bucket with enough cola to dissolve the rust (some rotating may be necessary).
If the rust is on the inside of the oven and you don't want to use cola, you can boil tomato juice inside the oven to remove the rust.
No matter which method you use, once you have removed the rust, you will need to wash and re-season your cast iron.
Note: If you have a VERY rusty oven, you can always take it to someone who can sand blast the oven to remove the rust.