Things You'll Need
Heat lamps (between four and six)
Paint brush or spray gun
Allow galvanized metal to weather for at least 6 months before you paint it. If you can’t weather it or it has been treated with chromates or silicates, clean it first with a solvent and then apply the paint to a test area.
If you are painting in an enclosed space, be sure to use a protective mask and vacate the room to let the paint dry so that you aren't inhaling the paint fumes for long.
Painting surfaces in the wrong temperature can ruin your paint job. If you are trying to paint a metal surface in temperatures colder than 50 degrees Fahrenheit, most paints won't dry. You can use a specially formulated cold-weather paint to combat this problem, but another way to paint metal in cold weather is to paint in a heated environment and to pre-heat the metal. A warm room and pre-heated metal will ensure your paint job lasts.
Bring indoors the metal to be cleaned. Remove all dirt, grease, oil oxide and any other foreign material using the cleaning solvent. Wear the protective mask to avoid inhaling too many of the solvent fumes when cleaning, and keep it on to avoid inhaling the paint fumes.
Heat the metal you are going to paint using strategically placed heat lamps. Place the lamps about 3 feet away from the metal and leave them on until the metal is warmed to at least 75 degrees. Modern paints need a temperature of at least 55 to 60 degrees for the paint to stick properly, so it's important to pre-heat the metal and keep using the lamps both while you paint and while the paint dries. Leave the heating lamps on for at least 4 hours after you apply the last coat or up to 6 hours.
Apply two mist coats of paint to the metal. Allow the first coat to dry for 15 minutes before applying the second coat. A mist coat is a thin layer of paint applied to the surface so that subsequent layers of paint adhere better. Generally, a mist coat should be applied about 12 to 18 inches away from the surface being painted.
Apply a wet coat of paint and leave it to dry for 15 minutes. A wet coat is the final layer of paint applied and adds gloss. Generally, the wet coat should be applied about 6 to 8 inches away from the surface being painted.
Based in Leeds, United Kingdom, Nicola Gordon-Thaxter has been writing sales articles since 1995. Her articles have appeared in the "Milton Keynes Citizen" and on the ePolitix website. Gordon-Thaxter holds a Bachelor of Arts in English literature from the University of the West Indies and is completing a Master of Arts in writing from the University of Leeds.