Outside metal furniture is tough, but it still needs to be cleaned to make it shine. Here’s how: Make a paste with 1/4 cup cream of tartar and baking soda, and then add 2 tablespoons of powdered laundry detergent.  Polish the piece with this paste and wipe and polish with a dry cloth.   Cover scratches with a permanent black marker for black metal furniture.

For areas missing paint or where rust has gathered, sand the area good and smooth with a 300 – 400 grit sandpaper (start with a 150 grit and work up, if it is really bad).   Then spray the area with a rustoleum type spray paint in a can, you can purchase at any hardware store.  Be sure the paint is rated for outside metal surfaces like rustoleum is.  You should put on at least 3-4 coats, let dry between coats, (about 3-6 hours), and sand lightly with a 600 or 800 grit sandpaper in between the coats.   Do not sand the final coat.