Scale modeling is one of the most popular hobbies for people of all ages everywhere. Making scale models can range from simple dolls to the most complicated cars, airplanes, trains and castles. All one needs to do to realize this is to look at the size of the Lego company and the range of designs it offers and continues to add to every day.

One of the most delightful and entertaining uses for the airbrush is to paint scale models like cars, airplanes and figurines. After the thrill of the assembly is over, the full beauty of the scale model depends upon the quality of the finish. The airbrush makes it possible for the hobbyist to apply layers of smooth coats of paint quickly and uniformly. It also enables the hobbyist to paint designs in great detail on the scale model, making them look as close as possible to the real thing.

For general hobby finishing, a Single-Action Bottom Feed internal mix airbrush is adequate. However, for fine detail model finishing, a Double-Action Gravity Feed internal mix type is preferred.

Enamels, lacquers and acrylic paints are most commonly used for scale model finishing work. Enamels and lacquers are harder to clean up and tend to clog the airbrush. The paint should be diluted to a consistency slightly thinner than milk. Enamel paints should be diluted with paint thinner, and acrylics with water or rubbing alcohol. At this consistency, air pressure should be set at around 20 – 25 psi.

Adequate protection like gloves, goggles and a mask when airbrushing scale models is required. Some paints, especially enamels and lacquers, will dissolve certain materials like foam. Testing the paint on a material similar to that of the scale model is recommended before applying the paint on the model itself.

After washing the scale model with dishwashing liquid and warm water, it should be dried, making sure that no lint remains on the surface. The parts of the model which are not to be painted should be covered with automotive masking tape so no sticky patches remain when the tape is removed. A black or brown paint primer is then airbrushed on the model. The dark colors will give the model added depth and shadows. The airbrush must be held at a 90-degree angle about 6 inches from the area and a light coat of the primer sprayed with each pass until a thick enough layer is built up. Enough time must be given for the primer to dry.

The final color is airbrushed onto the model and the layer allowed to dry. The paint is sprayed from a distance of 6 to 18 inches, depending upon the size of the area to be painted. As many coats as needed should be airbrushed to give the color enough depth, making sure each layer is dry before applying the next one. A clear paint coat should be airbrushed onto the model to give it a glossy finish and protect the paint. The clear coat is left to dry then one or two more coats airbrushed if necessary. The masking tape is removed after the painting is done.