Powder Coating over E-coat
Q. Our company makes parts, mostly out of cold rolled steel, for several products used in marine equipment applications. Our parts are now being primed with a liquid epoxy primer and finished with liquid urethane paint. We have been looking for ways to improve paint durability, and it has been suggested that we consider outsourcing our parts for application of an E-coat primer and a powder top coat. I am aware of applications where liquid paints are being applied over E-coat, but I am wondering about the feasibility of applying powder coating. Will the powder coating stick well to the E-coat? Could you give me some guidance on that? S.D.L.
A. Yes! Powder coating is being applied very successfully over E-coat in many applications today in several major industries. If the E-coat film is cured properly, there should be no problem with inter-coat adhesion. For your marine applications, I would say that someone has given you some very good advice. Corrosion protection has to be a high priority for you. Those two combined processes will give you the excellent coverage and corrosion resistance of E-coat plus the options of using various powder coating technologies and colors for wide design and styling flexibility. I would recommend that you move forward with a sampling and testing plan. I think you will be pleased with the results.
This paper is a peer-reviewed and edited version of a presentation delivered at NASF SUR/FIN 2012 in Las Vegas, Nev., on June 13, 2012.
How do you measure the surface area of a threaded fastener? How much coating would you put on it? How thick of a coating? What about non-threaded fasteners? The U.S. Department of Agriculture’s Forest Service, of all people, may have come up with the solution for those pondering how to coat sometimes-difficult small pieces using computer imaging and software to compute the area.
This paper is a peer-reviewed and edited version of a presentation delivered at NASF SUR/FIN 2012 in Las Vegas, Nev., on June 12, 2012.