Yesterday my oldest ds was rummaging around in my mom's garage. Sitting on top of one of her cabinets was a set of 3 cast iron frying pans. If I am not mistaken they were my grandmother's. Now mind you these pans are old. My mom is 90 yo and my grandmother has been gone since 1984. The pans have gotten rusty but he is hoping to save them (he is a pastry chef and loves using his cast iron). Any advice on how to clean them would be greatly appreciated. I will post a picture when I get a chance. Thanks in advance.