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Cleaning off dirt and debris helps keep the anodizing process running smoothly, and reduces the chances of imperfections as you work. Wash the object you want to anodize using a gentle detergent and warm water. Then, dry it completely with a clean rag or paper towel. Following the instructions on the product packaging, use your degreaser to remove any additional oil from the product. Wipe it away as necessary, making sure that no product remains on your metal before you move to the next step. In a small plastic tub, mix 3 tbsp. (44 ml) of lye in 1 gallon (3.8 l) of distilled water. Wearing a pair of rubber gloves, place the object you want to anodize into the lye solution. Allow it to sit for 3 minutes, then remove it and rinse it thoroughly with warm water.  The lye will remove any existing anodizing on the surface of the metal. Once it is removed, water should pour off the surface easily, instead of beading. Wear rubber gloves whenever working with lye. Do not use measuring spoons or cups that are used for food products. The materials used in this process are toxic.

Summary:
Wash your metal with soap and water. Apply a degreaser with a cloth. Dilute lye in water to create a scouring solution.