Polishing a Modern Cast-Iron Pan
16 December 2017
Can I improve a modern cast-iron pan? I’m a recent convert to using cast-iron pans. They’re cheap at about $25, they work great on an induction stovetop, and they make a mean steak, you should try it: https://cooking.nytimes.com/recipes/1016334-cast-iron-steak
Why polish my pan? Modern cast-iron pans like those from Lodge are very rough on the inner surface, probably the texture of the sand from the casting, and I suppose they save plenty by not machining them at all after casting. This means unless you fry your egg in a puddle of oil, flipping it for easy-over is tough. And some searching yielded lots of material — hey there’s a surprise lol. For example http://www.instructables.com/id/Iron-Skillet-Seasoning-Modification/
Fanning the flames, a friend gave me a vintage pan that his wife banned from the kitchen (!). The picture below shows the inner surface after I sanded off a few years of rust. Look at the circular machining marks! The cast surface was smoothed down by spinning this against some tool. The result is far smoother than modern pans.
That vintage pan got me thinking. Could I improve my modern pan that came straight from wally world? Here’s the “before” picture. This is a Lodge skillet that we’ve used to make some great steaks.
Well I don’t own a grinder but I have a sander and plenty of 80 grit discs, so I got to it. This next picture shows my progress after about 20 minutes of sanding. Yes I used a dust collector, no need to breathe more iron filings than necessary. I SHOULD HAVE STOPPED HERE. More on that later.
After about 45 minutes the base was VERY smooth so I stopped.
Then the seasoning. This means “varnishing.” I know that sounds gross but in the end you really are trying to create a thin layer of solid dried oil on the surface, just like that layer of stuff on your sheet trays after many years. Here’s a picture of doing it the WRONG way. A coleman stove is insanely hot in small areas, it burns off the oil instead of curing it.
To season effectively ya gotta use the right oil. Initially I used all the wrong oils. I tried bacon fat, crisco, canola oil. Nothing really worked. Finally I found this blog that convinced me to pony up the $1+/oz for flaxseed oil at my local health-food store: http://sherylcanter.com/wordpress/2010/01/a-science-based-technique-for-seasoning-cast-iron/
We followed the directions, put on a thin coat and baked it in a 450 degree oven upside down for an hour. That did NOT fill the house with smoke but it didn’t smell so great either. It’s tough to get the even finish you want all over, but we came close. With time I think the entire surface will darken to an even black.
Looking closely, I found that a thin layer of oil coalesces into tiny drops all over the surface, then those tiny drops turn into little plastic-like dots, very very tough to remove. With the next coat, more dots accumulate until eventually you get a reasonably even coating. So I’m cooking on plastic? Well, uh, it sorta seems like it. But it sure cooks a MEAN egg!
Update 6 months later: The baked-on oil came off while trying to clean clean some cooked-on carbonized sauce, something with sugar in it. The finish was more fragile than I expected, I can only guess that I polished off too many imperfections and now the oil cannot grab well. If anyone reads this far, don’t polish your pan down to a mirror, just knock off the high spots and call it a day.
Also see Stephanie Y.’s discussion of cast-iron cookware: https://campingcooks.com/cast-iron-cookware-user-guide/