[villagetinker]

I would contact (believe it or not) a marine service that repairs aluminum boats. Aluminum can be tricky to refinish, I have rebuilt around 10 cars, steel, fiberglass, and aluminum, the aluminum ones never turned out right. If you want to DIY, I would clean with TSP and a light sanding (do NOT use steel wool). This would be followed by a high quality automotive primer suitable for aluminum, and then a final coat of metal paint to match your existing bird cage.