When I find a piece of well used cast iron that is real crusty, I put it n my oven and run the self cleaning program. Takes it down to the bare metal, just dust. Then I wash it with SOS pads, rinse and put back in the oven at 300 for an hour. I then brush inside and out with crisco, then upside down back in the oven at 300 for about 2 hours, then turn off the oven and let cool in the oven. Now you have a seasoned cast iron piece, ready to use. Some use EasyOff with lye, but I prefer the oven method.

Pap