When using the Dave Platt wash effect on PPG Concept, use an enamel for the wash (such as Model Master) and use mineral spirits as the thinner. Mineral spirits will not affect the fresh PPG. Also, mineral spirits is good for removing the panel line tape residue from PPG. Concept can be used as a one part color (no clearcoat) for painting on your markings, etc, and is not affected by glow fuel. The only time a clearcoat, with Concept, is required is if a wash is used that is not glow proof (such as the Model Master). Good luck, Greg