Cast aluminum is used primarily for it’s resistance to rust and it’s ability to hold and distribute heat evenly. However, extreme temperatures and weathering may cause oxidation to form. This surface oxidation can be removed by using a mild soap and water solution and wash the grill as you would your car. A light coating of vegetable oil can be applied with a soft rag. This will add luster and offer protection to the outside of the casting. Coat the inside of the grill lightly with vegetable oil when it is new or when it is clean to give it extra protection from food acids. You can even refinish the casting by applying high temperature barbecue paint on the outside of the base. After the paint has thoroughly dried, bake it on by operating the grill for 15 minutes on a medium heat, then wipe on a light coating of vegetable oil.