- 1). Put on rubber gloves and clean the aluminum part with a dilute base or acid solution. A typical solution is two oz. of nitric acid in a gallon of water but there are many other acceptable choices. Thoroughly rinse the part with distilled water thoroughly. Place the part in the bucket with the acid solution.
- 2). Mix an electrolyte solution to conduct electricity. This will typically be a solution of 70 percent acid and 30 percent water in the case of aluminum. Fill the anodizing container with enough acid solution to completely cover the aluminum part. The anodizing container should be some type of insulating container, such as a rubber bucket.
- 3). Connect the negative lead of the battery charger to an aluminum electrode. This is typically a flat surface of aluminum that you can make with aluminum foil. Place the electrode in the solution and ensure that it doesn't touch the aluminum part. Attach the positive lead of the battery charger to the aluminum part.
- 4). Turn the charger on and wait for the surface of the aluminum part to anodize. The time required for the anodizing process to complete varies considerably, but you should see results within 15 minutes. Turn the charger off and disconnect the leads. Rinse the part thoroughly in cold water to remove the acid solution.
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