I pulled out one of the cast iron skillets I haven’t used in awhile and it has some very superficial rust on it. When I first got it, before I used it, I brushed a very thin coating of oil on it and baked it at 400 for about 30 mins. (Was that even close to correct?)
My instinct tells me to scrup the shit out of it, put it on high heat over a burner to dry it and cure it again. Another part of the same instinct tells me that’s the worst thing to do.
So what’s the best thing to do to neutralize the rust and cure the pan again?
I’ve never tried this, so I don’t know whether it works, but certainly the wire wheel method sounds effective.
If there’s not much rust, you can do what I’ve done before: scrub it like crazy, oil it, wipe out the oil (removing loose rust), scrub again, and oil it lightly to cure it.
I use a LOT of cast iron–most of my cooking is done in iron–and I’ve gotten all of my pieces from junk stores; all antiques! So I’ve done this several times.
If the rust is superficial, as you say, you can probably remove with just steel wool and water. Dry it on the stove top. Put it wet on a high flame, remove it when 90% of the water is gone.
Rub with oil and bake in a hot oven–I usually do around 300–for 30 min to an hour. If you smell burning oil, take it out. (Why I do it at 300 instead of 450.)
When it’s cooled a bit, scrub and rinse again. No soap. Just make sure to mechanically remove any excess oil. Dry on the stovetop again.
Viola.
Note: if you overdry and burn the oil off, just start over. (I do that all the time . . . my smoke detector is my only timer.)
What I learned on this very board a few days ago is that when you cure it you place it in the oven upside down (with a cookie sheet a few rungs down.) This will prevent the puddle of half cooked oil goo at one corner of the pan where the oil pooled that I have always gotten.
And someone recommended using crisco, bacon grease, or some other fat that is solid at room temp. Im not sure why though, vegetable oil has always worked fine for me.
In one extreme case I scrubbed a pan down to bright metal with fine emory cloth on a drill pad, but for a “very superficial rust” heroic measures shouldn’t be necessary. A little steel wool or a nylon pad (like a ScotchBrite pad) should be enough, proably won’t even need any cleanser, and then re-season as other posters have suggested.
Cast iron pans are great and underappreciated by the mass market, IMHO.
(When cleaning after use I don’t even use detergent at all unless there’s something really tenacious. Just scrub under hot water.)
Works even better in a grill - no burnt oil smell in the house.
To the OP, I have had to salvage some CI dutch ovens in my life. (Boy Scout troops don’t take care of their equipment unless someone volunteers.) Anything abrasive will do; I had to go out and get driveway sand to use with my steel wool - but that was some pretty stubborn rust.
I got a really nice 14" cast iron skillet at a garage sale, covered in rust. If you you have a self cleaning oven, just put it in there and run it through the cleaning cycle. It will burn off all the rust, after which you can wash it and cure it as normal.
My dad swears that cast iron isn’t properly seasoned until it has been heated in red-hot coals, burried in the backyard over winter, dug up, steel wooled clean, smeared with crisco and baked for days. My cast iron pans he gave me are slicker than any teflon pan I’ve ever seen. I never wash them. I burn them clean when necessary or wipe them clean or on rare occasion deglaze them by getting them hot and dumping water in them. My brother OTOH, swears that the only way to cure them is to put them on a campfire and cook a pound of the cheapest bacon you can find in it. I oil with melted Crisco and bake in a 200ish oven until my eyes water and all the oil is ‘absorbed’ then I reoil when the cast is a warm but touchable 100ish. I have trouble with the lid on my dutch oven rusting due to condensation from cooking soups in it. I rub it with a toothbrush when it is hot and the crap on it is soft to get the crusty rusty off. Then I rub with oil and put in a warmish oven after baking something (not with, it will ruin the taste). Most of all, do something, the rust will only get worse, and never ever give up on cast iron.
My wife just bought a brand-new cast iron skillet. The sucker’s HUGE- 15 inches at the bottom, weighs about 15 pounds, looks like something you could cook breakfast for a lumberjack camp in; and she got it at a surplus store for only nine dollars!
I tried an hour at 350 and the oil coating was still tacky. Put it back for an hour and a half- still kinda soft and gummy. Put it in our oven and set the timer for SIX hours at 350. That finally got the coating dry. It’s not black yet, sort of a dark bronze. I reread all the cast iron threads we’ve started and the advice for curing times all are for much shorter times than I used. Was I doing something wrong, or is it just that this pan is closer in size and weight to a dutch oven and needs to go longer?
And also, should the pan be shiny black before using or will that only come with actual use? I have one small fry pan that I’ve gotten a perfect black, smooth glossy coating on, and I’d really like to do right by this new pan.
Black is earned with time and use. As long as you have bronze and not gray iron, you are good to go. You might want to use it for oil-based dishes a few times before making chili in it for the first time. My loaf pan and muffin pans are all still bronze colored because they don’t get much use.
You don’t have to bake it until it’s dry. Just drop it in for 30 mins and then wipe it out when it cools. I think the point of doing it in heat is to open the pores of the iron and let the oil seep in, rather than changing the molecular structure of the oil.
Actually, you are changing the molecular structure of the oil. Oil polymerizes in the presence of heat, metal and oxygen. Here is a basic explaination from Penn State in the form of a .pdf file. Autooxidation is on the fourth page, and the factors affecting it on the 6th page.
You’re sort of making an edible varnish on your pan.