How To Spray Paint Galvanized Sheet Metal

When painting galvanized steel all paint systems used should be specifically formulated for use on galvanized steel and applied in accordance with the paint manufacturer s recommendations.

How to spray paint galvanized sheet metal.

The painting process is actually very straightforward because the surface of galvanized steel is relatively smooth and consistent. Avoid using alkyd based paints such as spray paint on galvanized steel. Paint that has lost its adhesion to a galvanized metal substrate e g. Alkyd and oil based paints may seem to stick at first but the oily layer eventually sheds the paint.

The acid in the vinegar will act to etch the metal and help the paint adhere. Galvanized metal is difficult to paint because it s coated with a layer of oil to prevent white rust. Once the metal has dried dampen a cloth with white vinegar and wipe the surface down. It also has surface contaminants oils greases residues etc left on the surface from the manufacturing process that interfere with the adhesion of paints.

The surface that has been painted. The choices of paint for galvanized metal will depend upon both the application and service environment. In fact roughly 69 of steel is recycled in north america each year. The enamels in alkyd paints can react with the slick zinc finish on a galvanized steel surface leading to poor adhesion and peeling.

On older galvanized metal surfaces where the zinc coating has begun breaking down known as white rust use a wire brush or fine sandpaper to remove the chalky film before cleaning it. Possible cause new galvanized metal a product used to make corrugated sheets gutters and downspouts is usually smooth and is coated with either a layer of oil to prevent white rust or is passivated.