How can I remove rust from an outdoor fireplace screen?

how about dont paint it or remove the rust......spray the screen with Pam cooking spray of even better rub it with lard or butter....it will turn a pleasant dark red to black color. there is really no paint other than a powder coat that will last....if you want to have a nice pretty black screen rub it down with warm beeswax and bake it in the oven at 500 degrees for a few hours....of course this will set off the smoke alarm and stink pretty bad.

Outdoor Fireplace Screens

Use a grinder wheel with a wire brush attachment. It's the only thing that will get into all the pits and grooves to remove the rust.

Use a phospheric acid based rust remover. As used on car repairs.

Use CLR cleaner and if that doesn't work try Mr.Clean Eraser, it is like magic!!!