I was ready an article on this written by Faye Stilley. His flames were copied from (enlarged) plastic model designs. The model used had no open bays. On the leading edge he used scallops to start and (3) different colors for the flames. All the flames had perfect butt fits. He accomplished this by laying the different monocote colors over each other when cutting - voila! Sure looked good. I've never tried it but it sounded good.