Using cast iron for cooking is one of the most inexpensive ways to cook clean in the kitchen. You can get a 12″ cast iron pan for less than $20. And they last forever.
Well, they can last forever. With proper maintenance. But sometimes life gets in the way, right? And your husband leaves your 10” cast iron, dirty, on the grill outside all fall and winter long…
I mean, in all fairness I didn’t remember either.
The point is, even when your cast iron pan has seen better days, it’s almost always salvageable. Your cast iron investment doesn’t have to go to waste just because of some rust.
With some patience, time, and elbow grease you can reseason a cast iron pan to be as good as new. Even if it’s rusty, moldy or just grossly dirty. You can reseason and refinish a pan multiple times throughout it’s life.
Here is what I was working with. I had a combination of mold, rust, and burnt on food. Ew.
So I started Googling how to reseason cast iron. Probably like your are right now. I decided to try a combination of techniques I found:
- Steel wool
- Coarse salt
- Soaking in vinegar
And if none of those worked, I’ve heard power sanders work pretty well too. I don’t have one though. So I probably would have had to buy another pan if everything else failed.
But one of these was bound to work, right?
Plain, old fashioned steel wool
You may have read to never use soap on cast iron. And what you read is correct.
But during this step of reseasoning cast iron, it’s ok to use soap. You’re trying to strip the surface seasoning here. You’re trying to get mold and grime off. And soap will help with that.
It’s once you season the pan for cooking that you don’t want to use soap anymore. That’s the seasoning you want to keep and maintain.
So, for my first step, I scrubbed the surface with the steel wool for well over 10 minutes. I tried to hit every inch of the surface.
For the amount of effort I felt I’d put in, it didn’t look that much better at all. Most of the mold was gone. But other than that not much changed.
I was using very fine steel wool. Perhaps a more coarse grade of steel wool would have been more effective for this step.
Again, after putting in what seemed like a lot of effort, the pan didn’t look as I’d hoped it would at this point.
Soak in vinegar
I thought maybe the rust had to be loosened and this method would yield the most improvement.
So I soaked the pan in distilled white vinegar for about 2 hours.
I probably should have soaked it longer in retrospect. But too much vinegar can cause more rusting if it soaks in the pores too far. So I wanted to be careful.
Note that if you have rust on the outside of your pan, you’ll want to find a container you can soak your whole pan in. And a lot of vinegar.
I washed and scrubbed again after this and it still wasn’t great. I felt the mold and food were taken care of sufficiently but not the rust.
So next was sandpaper
Sandpaper will literally strip the top layer of the pan. So depending on how deep the rust goes down into the pores will determine how many layers you’ll need to sand off.
I had a lot of layers to sand. And lots of surface area on the pan to hit. This method took me the longest.
I wasn’t trying to get it done quickly. I just left the pan and sandpaper near the sink and I’d sand a layer here and there over a few days whenever I’d get a chance. I’d say I probably stripped off a layer 15-20 times.
I would like to note I used Garnet and not aluminum sandpaper. Garnet is a little bit harder to sand metal with, but it’s not aluminum. Aluminum sandpaper’s grit comes off as you sand, so while you can wash it off, I didn’t want to take the chance of some residual aluminum being left on the pan.
But a bonus to the sandpaper method was that the pan is now smoother than it once was, almost if it had been machined!
Cast iron sanding times
Your sanding/scrubbing times will differ depending on a few different things.
- How rusty or dirty your pan is
- How big your pan is
- Which method you try first
- How long you can do a scrub sesh (I usually did two 10 minute scrubbings a sesh with a little break inbetween)
So the time it takes to remove all of the rust can differ a lot. I can’t say how long yours will take to sand, I can only tell you how long mine took.
What I was looking for was no more brown/rusty spots. So once I accomplished that, I would be done .
If you buy an unseasoned cast iron pan, it can look more silver like those specks on the sides. I either wanted the iron to be black or a silver/metallic color. Then I would be done sanding.
It ultimately took me a couple weeks of casually sanding it when I got the chance. So it also just depends on how often you sand. You could get it done in a day if you wanted.
So once you strip your pan down to clean cast iron, you can finally reseason it!
How to reseason a cast iron pan
Heat your oven to 450° F.
Take 1-2 tbsp of a good seasoning oil. I used avocado oil for this since it’s a high heat oil.
Pour it in the pan and spread it all over the inside and edges with a paper towel. Get the outside of the pan too while you’re at it.
Then put it in the 450° F oven for a good hour or two. The kitchen might get smokey, so be sure to turn on your fan or crack a window!
Turn the oven off and let the pan cool inside the oven.
Repeat this process a few times before cooking with the pan again. At least 2 or 3. But 4-5 is better.
Viola. A brand new reseasoned cast iron pan!
Is reseasoning a rusty, gross pan actually worth it?
That’s up to you.
Good cast iron is one of the cleanest materials you can cook with. Having more cast iron and thus nontoxic cooking options won’t ever be a bad thing!
Cast iron pans are relatively inexpensive these days. You might consider the cost of buying a new one to be worth less than the time and effort it takes for you to reseason the dirty one.
But maybe you have a cast iron that’s a family heirloom and the sentimental value is worth way more. Or maybe you have an expensive, high end cast iron like a Finex. Or maybe you just want to know that you can do it.
Whatever the reason. It’s (relatively) easy and cheap. It’s probably worth a try before running out and getting a new one.
Depending on the severity of the damage to your pan, one of the first methods that I tried could work for yours much better than it worked for mine. It could take you a lot less time and effort.
But if your pan is really bad. And you have that power sander. It can be really easy.