Things You'll Need
Coarse plastic brush
Spray etching primer
Spray acrylic latex paint
The etching primer will dry in two hours. However, wait an additional two hours for it to cure before you paint.
Never attempt to paint over a galvanized EMT conduit without removing the galvanized layer using a degreaser, or you will have problems with adhesion. Never attempt to paint over a galvanized EMT conduit without abrading it with an etching primer, first, or the finish will peel. Do not attempt to abrade a galvanized EMT conduit by sanding it with sandpaper as the surface is too hard and durable. Do not use a bonding primer in place of an etching primer.
Galvanized EMT conduits act as an electrical piping system that helps to protect and route electrical wiring. If you would like to paint a galvanized EMT conduit, you will need to contend with two issues. First, because the conduits are galvanized to protect them from rust, you will need to remove the oily coating, or you will have problems with paint adhesion. In addition, because metal is a nonporous surface, you will need to apply a special kind of primer that will abrade the conduit and allow the paint to stick.
Shut off the power running to the wires within the galvanized EMT conduit.
Scrub away the oily coating using a water-based degreaser and a coarse brush.
Rinse the conduit with a damp rag, and allow the surface to dry out completely before continuing.
Apply a light coat of etching primer to conduit, effectively abrading it to promote paint adhesion.
Allow the etching primer to cure for four hours, and then apply a coat of spray acrylic latex paint. Do not apply in a steady, constant stream. Apply in brief, intermittent bursts to encourage a smooth finish free of runs.
Ryan Lawrence is a freelance writer based in Boulder, Colorado. He has been writing professionally since 1999. He has 10 years of experience as a professional painting contractor. Lawrence writes for High Class Blogs and Yodle. He has a bachelor's degree in journalism and public relations with a minor in history from the University of Oklahoma.