Can galvanizing be reliably painted or powder coated?
Yes, galvanizing can be painted, but it may not be easy — especially if painting was not anticipated when the parts were galvanized. If you are a homeowner or hobbyist trying to paint a galvanized surface, the best advice (compiled from dozens of public forum threads on this site) seems to be: clean the surface with a scrub brush and a detergent like trisodium phosphate (TSP), rinse, neutralize the detergent and acidify the surface with diluted vinegar, rinse, apply a self-etching primer made specifically for galvanized surfaces. If you are a manufacturer, the above will not be good enough! The best plan, used by auto manufacturers, is to employ galvanneal steel rather than galvanized steel if you intend to paint it. Galvanneal has been annealed after galvanizing in a way that causes the steel and zinc to interdiffuse so that you are painting a steel alloy rather than pure zinc. Manufacturers may also wish to skip the chromate final dip if the parts will be painted because the brightn
