Stripping Cast Iron: A Guide To Removing Old Seasoning

Removing old seasoning from a cast-iron pan can be done in several ways. One method is to use a self-cleaning oven, placing the pan upside down and running the self-cleaning setting for 3-5 hours. Another approach is to use a fire pit or wood-burning stove, burying the pan in hot ash overnight and then washing it with hot soapy water. For those with access to a sandblaster, this can be an effective but risky method as it can pit the metal. A lye solution is another option, but caution is required when handling this chemical. Oven cleaner containing lye can also be used, sprayed on the pan and left for 24 hours before scrubbing. Finally, electrolysis can be employed, but this requires additional equipment such as a battery charger.

Using a fire pit or wood-burning stove

If you're looking to remove old seasoning from a cast-iron pan, one method is to use a fire pit or wood-burning stove. Here's a step-by-step guide on how to do it:

• Build a campfire in an outside fire pit or use a wood-burning stove to get some nice coals going.
• Once the coals have burned down and you're left with hot ash, bury your cast iron pan face down in the ash and leave it overnight.
• The next day, remove the pan from the ash. It will likely look like a mess at this point.
• Bring the pan inside and wash it with hot, soapy water. You can use steel wool to remove any remaining seasoning, rust, or flakes if needed.

This method is a simple and effective way to strip the seasoning from your cast iron pan without stinking up your house. It's important to note that this process may take some time and elbow grease, but it's a great way to restore your pan to its former glory.

Another similar method is to use an oven's self-cleaning function. However, this method will stink up your house, so it's recommended to do it on a day when you can open up all the windows. To use this method, set the pan upside down on the middle rack of the oven, close the door, and run the self-cleaning setting. Allow the pan to cool in the oven, then remove it and wash it with hot soapy water and steel wool if needed.

Using a self-cleaning oven

Step 1: Prepare the Oven and Pans

• Ensure your oven has a self-cleaning setting.
• Set your cast iron pans upside down on the middle rack of the oven.
• Open all windows in your house, if possible, as the process will produce a strong odour.

Step 2: Run the Self-Cleaning Cycle

• Close the oven door and run the self-cleaning cycle.
• Note: This cycle will take several hours to complete.

Step 3: Cool the Pans

Allow the pans to cool down inside the oven after the cycle is complete.

Step 4: Scrub the Pans

• Once the pans are cool, remove them from the oven and scrub them with hot, soapy water.
• Use steel wool or a scrubbing pad to remove any remaining seasoning, rust, or flakes.

Step 5: Rinse and Dry

Rinse the pans with clean water and dry them thoroughly.

Step 6: Re-season the Pans (Optional)

• If desired, you can re-season your cast iron pans after stripping.
• Follow a guide on how to re-season cast iron pans to complete this step.

Lye

Safety Precautions

Using Lye

If you are only removing the seasoning from one or two pans, it is recommended to use a product like Easy-Off, an oven cleaner that sprays a lye-based foam. First, spray the foam all over the cookware, then seal it in a heavy-duty garbage bag and let it sit for 24 hours. After this, scrub the pans with a heavy-duty scrubber to remove the seasoning. This may need to be repeated several times before the pan is stripped back to its original metal surface, which will be a gunmetal grey colour.

For larger jobs, or for a speedier process, you can fill a large plastic bucket with a lye solution and submerge the pans. You can buy lye at hardware stores, often in the form of drain cleaner. A one-pound bottle of lye should be added to five gallons of water, and it is important to always add the lye to the water, rather than pouring water onto the lye, as this can cause a violent reaction.

Leave the pans to soak in the lye solution for 24 hours, then scrub them. If they need more time, put them back in the solution and check and scrub from time to time until all the seasoning is removed. Lye will not harm the metal, so there is no risk of soaking the cookware for too long.

Important Safety Note

A bucket of lye solution is extremely dangerous, as dangerous as a pot of scalding hot oil. Keep children and pets away from it, and make sure it is stored securely when you are not using it.

Once you have removed all the old seasoning, the next step is to get rid of any rust. Thankfully, this does not require the use of lye; acetic acid (vinegar) will do the trick.

White vinegar

To use white vinegar to remove old seasoning and rust, you will need to follow these steps:

• Purchase big jugs of cheap distilled white vinegar.
• Fill a water-tight container with a 50/50 mix of distilled white vinegar and water. The container should be large enough to completely submerge your cast iron pan.
• Place the cast iron pan in the vinegar solution for no more than 30 minutes. It is important to monitor the pan while it soaks, as leaving it in the solution for too long can cause pitting, discolouration, and can even make the iron brittle.
• Remove the pan from the vinegar solution and scrub it with steel wool and/or a stainless steel brush while rinsing.
• Repeat the process as necessary, but for no longer than 30 minutes at a time.
• Once the rust has been removed, thoroughly rinse and dry the pan.

It is important to note that white vinegar will also remove the seasoning from your cast iron pan, so if you only want to remove rust, you may want to consider a different method. Additionally, be cautious when handling the pan after removing it from the vinegar solution, as the vinegar will make the cast iron very slippery.

Electrolysis

To use electrolysis to remove old seasoning from a cast iron pan, you will need the following:

• A plastic tub or container large enough to submerge the pan
• Cold water
• Washing soda (1 tablespoon per gallon of water)
• Battery charger (6V-12V)
• Rusty cast iron pan
• Scrap steel
• Steel wire (e.g. rebar tie wire)
• Power supply

• Fill the plastic tub with cold water and add 1 tablespoon of washing soda per gallon of water.
• Position the cast iron pan and scrap steel in the tub, ensuring they are fully submerged and not touching each other.
• Connect the positive (+) battery charger cable to the cast iron pan and the negative (-) cable to the scrap steel.
• Power the battery charger at 6V-12V. The cast iron pan should start bubbling within a few moments.
• Let the electrolysis process run for 6-12 hours, or until the rust and seasoning have been removed. This may take longer depending on the amount of rust and seasoning, the size and position of the scrap steel, and the amperage of the power supply.
• Once the rust is no longer visible or has turned black, remove the cast iron pan from the tub.
• Rinse the pan in a sink or outdoor area using cold water and scrub with a steel wire brush and/or steel wool to remove any remaining residue.
• Dry the pan thoroughly and proceed to the re-seasoning process.

It is important to note that electrolysis is just one method for removing old seasoning from cast iron pans. Other methods include using a lye bath, oven cleaner, vinegar, or a self-cleaning oven. Additionally, proper maintenance and care of your cast iron pan can help prevent the need for such intensive cleaning methods.

Frequently asked questions