CN Spots, ModelCrazy, Spru-ceGoose, sorry it took so long to get back to you. To answer, because I only use rattlecan (for personal reasons), I found that the primer sticks to the plastic much better than the top coat does to the primer. So, after layering the orange top coat on the dark grey primer, I use an X-Acto knife to induce the chipping through scrapping of the dried orange top coat, revealing the primer, but the primer stays un-chipped. Then, in certain areas, I use good 'ole Testors enamel silver in a bottle to paint within the primer chips, the look of bare metal. That's it, guys!