This invention is a method to coat an object or non-ferrous plate with a non-porous polymeric coating that has excellent adherence to the non-ferrous substrate. The process includes the following steps: conditioning or chemically treating a non-ferrous substrate surface; heating the substrate to a temperature above 180° C. but less than the ignition temperature of the plastic coating; applying a first layer of plastic material to the heated surface, immediately applying a second plastic layer onto the first plastic layer which is maintained at a minimum temperature of 180° C.; reheating the two plastic layers at a temperature from 180-280° C., to produce a smooth non-porous surface: and allowing the substrate and plastic coating to cool.