Micro-Mark Airbrush Paint Thinner When it comes to achieving the perfect consistency for your airbrush acrylic paints, it can be a delicate balance. Too thick, and you risk clogging your airbrush; too thin, and you compromise on color and adhesion. That's where Micro-Mark's Airbrush Thinner comes in - a specially developed medium designed to adjust the viscosity of water-based airbrush acrylic paints without sacrificing performance.