How I Remove Rust From Cast Iron

Now that we’ve made it through our rainy, Virginia springtime; we’re overdue for some outdoor chores. At Arthurized Home, we use cast iron for our everyday cooking. We’re careful to season it regularly so rust is not a problem. However, I just bought a cast iron pot with some pretty severe rust on it. It’s not pitted, so that’s good. Actually, I would have passed on buying pitted cast iron. No amount of TLC can bring that back.

A quick Google search shows countless methods for removing rust from cast iron. The process I’m using is one that I have used successfully over the years. I burn the rust off the cast iron in a fire and then season it in the oven. This method avoids using noxious chemicals and hours (and hours!) of obnoxious scrubbing.

My cast iron is good quality and very serviceable, but solidly average. It’s not rare or valuable. I would not use this method on Granny’s heirloom cast iron. For that, I would get out the steel wool, get to scrubbin’ and develop tendinitis.

I can’t speak to whether vinegar baths, oven cleaner (seems toxic), electrolysis and lye baths work on rusty cast iron, because I haven’t tried those methods.

Cast Iron Care: Take care not to shock your cast iron, which can cause it to crack. Bring the cast iron to temperature along with the heat source. Never place cold cast iron onto a hot stove, into a hot oven or fire. Never place hot cast iron into the fridge/ freezer, cold water or an ice bath. Remember ‘hot with hot’ and ‘cold with cold’ and your cast iron will be just fine.

Pa Kettle decided to get in on the action by providing an actual kettle that he found in his basement when they bought the home. It’s been unloved and in Basement Purgatory for 50+ years. I’m not sure if it is salvageable, because the rust is thick and the pot is severely pitted. But, why not throw it in and see what happens?

This is a good project to start in the morning, as you need several hours for the fire and several hours for cooling. To prepare the fire, I placed a few logs into the fire pit and laid the pots on top. I positioned the pots so that as the logs burned down, they drop toward the center of the fire, not out of it. Then I covered the pots with more logs. The idea is to have the fire reach the entire pot, including the undersides.

Bring out a few of those great fire starters and put them to work. Once you have a roaring fire, it’s time to relax.

Contemplate the meaning of life, sing a few campfire songs and break out the hot dogs or s’mores fixin’s.

Without leaving the fire unattended, burn the cast iron for a few hours (I like a minimum of three hours) and then let the fire die out.

Don’t pour water to extinguish the fire, as that could shock the cast iron.

Once, the ashes cooled, I pulled the pots from the fire pit. See that red stuff? It’s red rust. This is oxidation at high temperature when raw metal is exposed to the air. Not to worry, though. A quick scrub with a paste made of baking soda and a splash of water, will take most of that off. I’ve read that a thin coat of red rust helps the first layer of season to bond. I have no idea if that’s true, but I’ll soon find out!

Pa Kettle’s pot will need another turn in the fire.
I would like to get all of the brown rust off of it before moving on to the next step.

Thoroughly rinse the baking soda off of the cast iron. If all the old season has been removed and the raw cast iron is exposed, the pot should be matte grey.

I placed a large baking sheet onto the lowest oven rack and put the pot on the top rack. I turned the oven to 300° and left the pan in for about five minutes. This ensures that the pan is completely dry before seasoning.

After drying the pot, let it cool a little, then season with oil or grease of your choice. I spread an extremely light layer of bacon grease over the pot, coating it entirely. Wipe excess grease off with a paper towel and place the pot back into the oven upside down. This allows any excess grease to drip out of the pot onto the baking sheet below. I usually season my cast iron between 375° and 425°, so I crank the oven up at this time.

After about an hour in the oven, I turn it off and let the cast iron cool down. Then I repeat this step. Again. And again. And again; building thin layers of season each time. Once the season is built up on the pot, it is ready for daily use in the kitchen.

A few more tips on cast iron care: Moisture is the enemy of cast iron. Never let cast iron soak in water. After use, and while your pans are still warm, quickly rinse, dry and re-oil your cast iron. If there are food particles cooked on, use a plastic scrub brush to remove them.

Cast iron is for cooking and baking, not food storage. You’ll need some vintage Pyrex refrigerator boxes for that. *winks*

Because our kitchen is small, we stack our cast iron for storage. Scratches can damage the season, so we place a microfiber cloth between each pan.

Take good care of your cast iron and it will serve you for a lifetime. Who knows; maybe the grandkids will fight over your collection one day?

For more reading on caring for cast iron, here’s an interesting article:
https://richsoil.com/cast-iron.jsp#seasoning

Disclosure: In addition to occasional sponsored posts, Arthurized Home uses clickable affiliate links. That means that I may receive a small commission from sales at no extra charge to you. As always, my opinion is 100% my own, and I only recommend things that I truly love or use myself. Thank you for patronizing the brands that support Arthurized Home!

Copyright 2019 © Arthurized Home – All Rights Reserved. This post is the original content of Arthurized Home. If you’re reading this on another site, it’s unArthurized.

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