Frequently Asked Questions

Cast Iron Care/Rust issues and prevention

Pre-seasoning: the “coating” is heated soy oil, the same of which is used on Dutch ovens and lodge pans. When vegetable oils, lard, Crisco, bacon fat, etc... get heated they polymerizes, i.e. turn into a sticky goo. First yellow, red, then black. It protects the cast iron from rust and provides the non-stick properties pre-seasoned cast iron is known for.

However, since the coating is just "dried" oil, its not as durable as enamel or powder coating and needs to be preserved and maintained. Heat will burn it off, moisture will soften it and acid will eat away at it. Ideally after grilling, you should close the vents of your grill to snuff out the coals and come back after your grate has cooled and do a quick scrape with a spatula. If your grate has turned grey, you should oil it with a paper towel, sweep the ash away and leave your grill open a little bit open. Of course doing this after every cook is not always possible, but the longer your grates stay unprotected (unoiled) in a hostile environment (humid and gunky) the more TLC is required before your next cook. Humidity softens the coating and makes it gooey, till eventually the moisture reaches the iron below.

If you are not going to be grilling for some time, brush your grate thoroughly and oil it before storing. Ash and old coals in the grill will attract moisture which may be more severe if you live somewhere humid. Cleaning out your grill and leaving the bottom vent of your grill open for air circulation prevents that. Gunk will also eat away at the seasoning (tomato and vinegar for example are acidic). I scrape with a cheap hardware store spatula; most gunk will just flake off. Brush a bit before grilling.

The residue/gunk left on the pre-seasoning after your last cook is acidic and will eat away at it, there is acid in sauces or tomatoes. High heat will burn it off. Most non fatty things like steak or chicken breast are grilled over high heat and you will notice the color change from black to dull grey after a few cooks. Brush your grates with oil or Crisco and the black will come back. It also helps to alternate the inserts that sit over the fire. If you grill fatty foods as well, sausages, wings, pork shoulders, then this should be no problem. Should your grates be rusty, heat them and brush afterwards. You remove the old coating and the rust, oiling fills the metal pores to prevent rust again and heat will turn it back into a protective goo. Light one chimney of charcoal, Take out the inserts and dump the coal evenly in the 4 openings. Put the inserts back, close the lid and completely open top and bottom vent. Heat the grate at full power for maybe around 45 min. Brush with a stiff brush, dip a paper towel in vegetable oil and oil the grates with your tongs. They will be black again. Ideally you grill some fatty foods once or twice, bacon wrapped or chicken wings, ideally pork shoulder. And they will look like new.