>>If cast iron was porous, it would puff up like a sponge when you used anything fluid in it...or leak if you used it for a slow cook.

There are different degrees of porosity. Wood is very porous yet holds water. Concrete, ceramic, clay, and some plastics - all porous yet all hold water quite well. ALL are porous to the extent that they will hold residue. Use garlic in a wood bowl and you'll smell it forever, yet it will hold water without leakage for many many years.

One of the reasons that cast iron skillets have to be "seasoned" is that the metals are porous to an extent - it's more of a "pock marked" (albiet small) than it is truely porours (like wood) - but these pock marks hold residue - in the case of skillets the residue is the oils that were used to season it.

While I doubt that using a harsh cleaner on the outside would "soak through" the skillet (because it's not *that* porous), I still wouldn't do it as there is no guarantee that when your rinsing the stuff off it wont drip onto a part of the skillet that may touch food and once the residue is there - it will be hard to come off.

Not only that, but I don't know if I would want that chemical residue on the outside of the pan the next time I put the pan on a flame - no idea of oven cleaner is flamable or combustable.

Oven cleaner is lye. It's not flamable or combustable. WAGS has an article written by a leading scientist about whether or not cast iron is porous, and lends his expertise and knowledge to the subject. I choose to believe him.

As for the cleaning of the cooking surface. I would not, for me, half clean a pan. If I'm going to clean it, I'm going to strip it completely and start over. I'm going to use lye to do it...and I'm going to wash it well afterward before I season it. If by chance and it's a slim one, there is any lye left on the surface, the fat in the oil I use to season it is going to neutralize it. (That's how soaps are made...read somewhere that if it doesn't have lye, it's NOT soap) Don't know that ingesting soap has ever killed or hurt anyone...

Cast iron is easy to reseason once it's stripped. Why do a halfway job?

Interesting discussion. Lots of things to consider and I appreciate them all. I will check out the website WAGS too. Thanks, I knew this was the place to come.

I have made laundry soap - & yes, the 'recipe' uses lye; hasn't killed us yet.
Good point re: doing whole vs halfway job on cleaning - will remember that next time I need to reseason a pan.

Thanks everyone for interesting discussion.

I’ll have to disagree with not using soap on cast iron skillets. My wife and I have a whole fleet of them and have been washing ours in dish soap, rinsing with plain water and setting them in the drainer to drip-dry for the past 36 years. Most of them were handed down to us from relatives that did the same thing for years before us. If they’re seasoned properly, mild dish soap won’t hurt them. If one starts rusting, it didn’t get seasoned well, and it needs to be done again.

We cook almost exclusively with cast iron skillets. We use a ChoreBoy metal scrubber to scour them inside and out when needed too.

I’ve never understood greasing them after use. It seems like greasy pans can get rancid, and/or attract every bug in the country.

CD in Oklahoma