For mud effects requiring an air source, I use my 12 volt tire inflating device, along with a Testors glue tip (which happens to be the exact same size as a Schrader valve stem). For the chipping technique involving an acrylic paint applied over hairspray, I use Montana Gold's line of acrylic rattle can sprays. And for the application of enamel washes and filters over my rattle can enamel base coats, I also use either Montana Gold's acrylic gloss or matte clear, as the protective coat. I refuse to get an airbrush for personal reasons, and like the challenge of utilizing alternative products and techniques. The main draw back with this reasoning, however, is the inability to mix different shades of one color, when applying the modulation technique, or when a very specific mix of colors is required, to duplicate a shade that is very peculiar to a particular armor. I have not reached that point yet, and for now, I'll continue to model sans compressor and airbrush.