What type of paint - metal porch railing?

The obvious choice for 50 years has been Rustoleum. Use a brush if you're a sloppy spayer, and prime first with Rustoleum primer (red). Don't get in a hurry. To work effectively the resins in these products need time to penetrate well and hence cure somewhat slowly. The company makes automotive types of primers (gray) and paints, too. These are not what you want. HTH

Joe

Good Ol' Rustoelum

Brush on

Prime with the rusty metal red lead primer first.

If your railing is easily removable (iow, not trapped in the concrete, but set in those little socket things), I'd take to a metal finishing company that can shotblast the whole thing down to clean metal, and bake on a commercial-grade finish. It would cost more, but the finish would outlast you. If it isn't easily removable, what the other guys said about rustoleum is the way to go. I'd use a brush- spraying looks prettier, but you have to use multiple coats to get as thick, and the overspray goes everywhere. Get a good wire wheel, and use your oldest crappiest drill, since it will get filthy inside and out. Protective eyewear is a must, as is a dust mask. Don't think you will get the rerusting done in one session- your wrists will get tired rapidly. Clean a section at a time, wipe down with solvent like liquid sandpaper or something to degrease, and cover the bare metal with primer, or it will rerust overnight.

aem sends....

If you can get down to bare metal, put a coat or two of Extend on it, let it cure, then paint with the rustoleum. Extend is a rust preventative -- better than any primer. Available at Ace, HD, automotive paint stores, etc.

-chib