Powder coating applies a layer of free-floating, dry organic powder by electrostatic attraction to metal. The piece is first cleaned thoroughly to ensure even adherence of the powder. The powder can be polyester, polyurethane, polyester-epoxy, epoxy, or acrylic. After grounding the piece, a surge of high voltage electricity charges the dry powder. The charged powder is sprayed evenly over the entirety of the metal piece. To complete the process, curing occurs for 10-15 minutes in an oven up to 400 °F. During the curing process, the powder sets, polymerizes, and flows around the object forming a thick protective layer.
The benefits of powder coating are abundant. First, powder coating results in a thick, dense finish that is resistant to scratches, chipping, and splintering. If bending or denting occurs, the powder coating will remain intact where a traditional wet paint would chip fall off. The durable coating is long lasting. Another benefit is the ease of use and cleanup. Most projects only require one coat to achieve a perfect finish free of drips or brush marks. Because no is solvent involved, any excess powder can be swept or vacuumed up. This also makes the process environmentally safe.
There are only two major drawbacks to the powder coating process. If a thin finish is necessary, powder coating is not ideal. Thinning the polymer produces a bumpy finish rather than the slick coating produces with thick layers. Secondly, smaller jobs might prefer a less expensive finishing process, as powder coating requires spray materials, electrostatic booth, and a dedicated oven, all which can be expensive startup costs. Maintenance, while not required as often as wet paint, is more difficult. Touch ups to damaged areas are more difficult than simply touching up with a can of paint.