Step 1
Lightly sand the surface of the door with 220-grit sandpaper. Sanding will provide a surface that the cladding paints can adhere to and help remove surface grime. Wipe the door down with a clean rag when you have finished sanding to remove the sanding dust. Painting over dust can cause the paint that you apply to prematurely fail.
Step 2
Wrap painter’s tape around the base plate of the doorknob where it meets the door. Cover the edge of the hinges that meet the door as well as the door latches with painter’s tape. By using tape, you will not have to remove the door.
Step 3
Slide a drop cloth underneath the door to prevent paint splatter. Place a heavy object behind the door opposite the side you will be painting. The object will keep the door from moving while you are painting it.
Step 4
Apply a bonding primer designed for metal to the surface of the door. Use a paintbrush to cut in around the doorknob, latches and hinges. Prime the larger flat surfaces with a 4-inch foam roller. The foam roller will eliminate brush marks and give the appearance of a sprayed finish. Allow the primer to dry according to the manufacturer’s recommendations.
Step 5
Cover coat the door using top-quality enamel paint for metal. You can purchase this type of paint at your local paint store. Use the same painting techniques in the previous step. Apply a second coat after the first coat has completely dried.