1. Sandblast or to fake it sand with 180 grit. you want to get an even sheen of scratches. the dust removed is aluminum oxide, clean very very good with lacquer thinner, MEK, acetone or the likes. Then you must paint before 8 hours has elapsed. After 8 hours the part will oxidize, and again resand and clean.

    2. Use wash primer. It is a primer that contains phosphoric acid. Very bad for the health, eyes, and skin, so use your head and be careful. This is obtainable from auto paint stores. It is a two part primer that goes a very long way for you only spray .5 mils at max. It will be transparent, very light olive drab color. To spray a complete computer case you will only use 1/4 pint to around 1/2 pint for the largest cases. The two parts to this primer are the Primer itself and reducer/catalyst. It is usually mixed in a ratio of 1 part primer to 2 parts reducer/catalyst. Remember to use eye protection, wear something to cover all exposed areas of skin, and to wear a vapor protective mask. Spray part lightly, almost barely putting any on. you want to be able to see through the primer. Then let the part(s) set for a minimum of 30 minutes, this allows the acid to etch the metal. Then if needed spray on regular primer or a ground coat if spraying special effect paint. Then spray topcoat in thin even coats allowing time to flash off in between coats.

    TIP. the best method with some paints in a rattle can is to use a method where you spray a mist coat allowing a few moments to dry a little, or letting it get sticky, then spray a heavy coat but not running or sagging, then a quick light coat. with this tip though it is best to practice on something else to get the method correct and not to mess up your project.

By ronbo2525