What is how to remove rust from cast iron?

Removing Rust from Cast Iron

Rust on cast iron is a common problem, but thankfully, it's usually removable. Here's a breakdown of some effective methods:

Vinegar Soak: Submerge the cast iron in white vinegar (diluted 50/50 with water for heavily rusted items) for a few hours. Check frequently (every 30-60 minutes) to avoid over-soaking. The vinegar's acidity loosens the rust. After soaking, scrub with steel wool or a scouring pad. Rinse, dry thoroughly, and season immediately.
Baking Soda Paste: Create a paste of baking soda and water. Apply it to the rusted areas and let it sit for a while. Scrub with a scouring pad or steel wool. Rinse, dry thoroughly, and season.
Salt and Potato: Cut a potato in half. Sprinkle salt onto the cut side. Use the potato to scrub the rust. The oxalic acid in the potato helps dissolve the rust. Add more salt as needed. Rinse, dry thoroughly, and season.
Electrolytic Rust Removal: This is a more advanced method that uses an electrical current to remove rust. It involves a container, water, washing soda (sodium carbonate), a sacrificial anode (like a piece of rebar), and a battery charger. Research this method thoroughly before attempting, as it involves electricity.
Commercial Rust Removers: These are chemical solutions specifically designed to dissolve rust. Follow the manufacturer's instructions carefully, as some can be harsh. Wear appropriate safety gear (gloves, eye protection).

Safety First: Wear gloves and eye protection when using chemical rust removers or when scrubbing vigorously.
Thorough Drying: After removing the rust, thoroughly dry the cast iron. Even a small amount of moisture can lead to re-rusting. You can dry it in a warm oven.
Seasoning: After removing rust and drying, immediately season the cast iron to protect it from future rust. Seasoning involves coating the pan with a thin layer of oil and baking it at a high temperature.