Why does cast iron skillet rust

The minor pitting on the cooking surface of the pan above could interfere with an otherwise seasoned finish, though it may be possible to build up enough seasoning to overcome it. Before buying, it's best to read up on cast-iron defects, including pitting and warping, and whether they're surmountable or not to make an informed decision. Once you have your cast iron, there are generally two things you'll likely need to do: remove the old layers of seasoning and also get rid of rust.

Once a pan is beat up enough, it's not worth trying to salvage the seasoning that's on it. For a really beautiful, functional piece, you're going to want to strip that baby down and then build it back up from scratch. First, a tip on what not to do. Some sites will tell you to use Naval Jelly, a form of phosphoric acid. The photo above is of a pan that had Naval Jelly painted onto it. It dries on, as you can see, and then becomes very difficult to remove.

According to Nick, it can work for very small pieces of cast iron that can be fully submerged in the jelly, but most cookware is just too large. Sandblasting is another method Nick says to steer clear of: it not only cleans everything off, it also permanently alters the original surface of the cast iron. The seasoning on cast iron is polymerized oil, essentially a plastic-like coating that forms when oil is heated in the presence of the iron and oxygen.

Lye, the common name of the alkaline compound sodium hydroxide, can break down that polymerized oil. Like hot oil, when handled responsibly, it can be used without trouble—just like frying oil, don't get it on your skin. Make sure to use heavy-duty rubber gloves and eye protection, and keep the rest of your skin covered. If you have one or two vintage pans, the easiest thing to do, according to Nick, is to use a product like Easy-Off, an oven cleaner that sprays a lye-based foam.

To use it, spray the foam all over the cookware, then seal it in heavy duty garbage bags and let it sit for 24 hours. Then scrub the pans with a heavy duty scrubber to remove the seasoning and strip the pan down to its original metal surface, which you'll recognize by its gunmetal gray color. The downside of Easy-Off is that it will often take several applications and scrubbing sessions before all of the seasoning is removed. For larger jobs, or if you want speedier results, the next best option is to fill a large plastic bucket with a lye solution and submerge the pans in that.

Nick buys lye at hardware stores, such as the bottle of drain cleaner you see above just make sure the product you buy is pure lye. He adds the one-pound bottle of lye to five gallons of water, and again, take note: you should always add lye to water and not pour water onto the lye, since that can cause a violent reaction.

Nick lets the pans soak in the lye solution for 24 hours, then scrubs them. If they need a little more time in the lye solution, he puts them back, checking them and scrubbing from time to time until all the seasoning is removed. The good news is lye won't harm the metal at all, so there's no fear of soaking the cookware for too long in the lye.

One more safety note: a bucket of lye solution is a dangerous thing, as dangerous as a pot of scalding hot oil. Keep children and pets far away from it, and make sure the lye is not in a place where a curious child or pet could find it on their own; also always keep the bucket securely covered when you're not working on the pans. You can see in the photo above that the skillet has just a little more seasoning left the dark spots before it's ready to be rinsed and then moved along to the next step.

Once you've removed all of the old seasoning, the next step is to get rid of any rust. Thankfully, removing rust doesn't require anything as nasty as lye: acetic acid, A.

Make sure to buy big jugs of cheap distilled white vinegar for this. Nick lets his pans soak in the pure distilled white vinegar for six to twelve hours, then scrubs it.

But he warns not to ever let this step go longer than 24 hours—vinegar may not present much of a problem to our skin, but it will erode and pit the cast iron if left on for too long. I love these photos: you can finally see the original cast iron emerge. Nick labels each bucket so that there's no confusion about which one contains lye and which one contains vinegar. There's just a little rust left on the handle, but otherwise this skillet is ready for its new life.

Just note that once exposed, the cast iron will begin to rust almost immediately from the air alone. To prevent that, oil the pan as described below right away.

For those who want a solution that deals with the seasoning and rust simultaneously, look no farther than an electrolysis setup. This isn't practical for a lot of people at home, but car enthusiasts may already have the battery charger on hand. If that sounds like you, read on. Nick runs his with this Schumacher charger that he sets to 10 amps. He connects the positive red clamp to a steel plate in the tub and the negative black clamp to the pan being cleaned.

Here are five common problems with cast iron and how to fix them. There are a lot of opinions when it comes to how to best clean cast iron. Some swear by salt , and others use specific metal tools to keep their pans at peak performance. However, the truth is that you can clean your cast iron pan just like any other pan—with water and yes, soap which won't hurt your seasoning.

The key is to make sure your pan is bone dry after you clean it. Cast iron and long term exposure to moisture are not friends so rather than obsess over the best way to clean the pan, just focus on avoiding rust.

We promise, seasoning a cast iron pan is way simpler than you think. Simply coat the entire surface of your pan with a thin layer of vegetable oil and place it upside down in a degree oven for an hour make sure to put a sheet of foil on the rack below to catch any drips. Then turn the oven off and leave your pan inside the oven until the pan itself has returned to room temperature. Simply wash your pan with warm water and a textured sponge and wipe with a dry towel.

To ensure no rust will come to your treasured pan, a quick heated dry in the oven will do. For more tips on how to properly clean and care for your cast iron, visit our friends at Lodge. Their centuries of cast iron manufacturing means they've seen it all, and we turn to them for help with our own cast iron issues. By Cooking Light Contributor December 25, Pin FB More.

Eating healthy should still be delicious.