Stripping & Reseasoning Cast Iron

Corv

These are my experiences. I had an old cast iron skillet that had such a build-up of seasoning that the bottom wasn’t smooth. Time to redo it. I bought that skillet when I got out of the Air Force in 1972. Kmart sold it to me. It’s a little on the light side but the inside is quite smooth. I like it a lot.
I used my pizza oven to burn off the old seasoning from a skillet, with the skillet on the oven stone from cold. It took about 10 or 15 minutes to get the skillet to 900 F, which was more than ample. I used an infrared remote thermometer to measure the skillet temperature.
If you get one of these thermometers, verify the highest temperature it’ll read before you buy it. The majority of them only to up to about 740 F, but some go up to 1,200 F or higher. Those are the ones to look for.
Once the skillet reached 900 F, I shut the Roccbox off and let the skillet cool down. I don’t remember how long that took.
It was covered with white ash. I made the mistake of washing the ash off in the sink under running water, and the skillet immediately rusted. Well, that proved it was down to bare metal anyway. I used Scotchbrite to remove the rust and isopropyl alcohol to clean it up. No more water for washing off ash.
I chose peanut oil for the reseasoning because I had plenty and it has a higher smoke point than olive oil, also on hand. Avocado oil would have done as well. I rubbed on a very thin layer of oil on every surface of the skillet, including the handle. And then I used a paper towel to remove any excess oil. All I wanted was a very thin coat, lest it build up like what I’d just removed.
With the skillet upside down in the cold oven (I’d taken out the baking stone that normally resides there, so the skillet was directly on the middle rack), I cranked the oven temp up to 500 F. That’s as high as my Bluestar oven will go, unfortunately. The convection was on to help ensure even heating, and the stove exhaust fan was going, too.
About an hour after the oven came to temperature, I shut it off, but left the door closed until I was sure the oven had cooled. Yes, I had the exhaust fan going when I opened the door.
The skillet had an even coating of seasoning, but it was too thin. So I did the seasoning step again. This time it came out nicely, and using it has shown that this is a well-seasoned skillet.

Ozzie_Isaac

How do you recommend washing the ash off?  Maybe just straight alcohol?

Ozzie_Isaac

I tried grape-seed oil for seasoning since the oil we supposed to have good “polymerization”, it looked beautiful and was slick as snot, but delicate.  I have better luck with cheaper oils like canola or bacon fat.  I will try peanut oil next time.

Corv

I think straight alcohol will do it, since at this point (post 900 F) the ash is powdery.

I used peanut oil because it would do the job and was handy. But maybe the best oil to use is a topic for a stand-along thread. I have found that oils with higher smoke points seem to do better than ones with lower smoke points, and have a personal objection to canola oil because it comes from genetically modified rapeseed. Yes, I know that canola oil is widely used - just not in my kitchen.

zaphod

I recently did a waffle iron with grape seed oil. Years ago I seasoned a dutch oven so badly that it went rancid. It never lost that taste/smell even after tossing into a campfire for a while so I gave it away.  This time I followed these instructions and the CI came out just fine. YMMV

https://sherylcanter.com/wordpress/2010/01/a-science-based-technique-for-seasoning-cast-iron/