How to Prime Exterior Metal Pipe
- 1). Scrub each exterior metal pipe with a water-based de-greasing cleanser, using durable, coarse steel wool. This is a fundamental step; don't bypass the cleaning process, or the primer may not adhere.
- 2). Rinse the metallic piping, using a pressure washer. Don't use a water hose, or trace cleanser residues may be left upon the metal. Let each metal pipe dry for at least three hours.
- 3). Position canvas drop cloths beneath the exterior metal pipe. Affix a low-tack painter's masking tape to surfaces adjacent to the pipe.
- 4). Coat the exterior metal pipe with galvanized metal-etching primer, using a 2-to-4-inch nylon paintbrush. Apply a thin coat to prevent runs and drips; apply gentle pressure with the nylon brush. Let the exterior piping dry for at least three hours.
- 5). Wash the brush three times, using clean water from a hose.
- 6). Coat the exterior metal pipe with exterior acrylic paint, using the nylon paintbrush. Paint as you primed. Let the exterior piping dry for at least three hours.
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