The proper finish on a model is the crowning touch of the construction process. A good paint job requires planning and patience. Special painting techniques require practice and experience. The painting process allows you to show your creativity and attention to detail. With experience, the selection of paint and application method will become second nature. You can strive for historical accuracy or individual creativity. The variety of available paints and tools for applying finishes offers the modeler the opportunity to separately detail and design each model.
Choosing the Paint
Model paints come in latex, acrylic, enamel and lacquer bases. Latex and acrylic paints are water-diluted paints that dry relatively fast. They may require special chemicals to remove them after they dry. Enamel paints generally take longer to dry than other types of paint. This allows a longer working time ("pot time"). Enamels and lacquers are solvent-based and require care in handling because of potential flammability and toxicity. Unlike enamels, lacquers generally dry quicker than the other types of paint. Each type of paint has its own characteristics and applications. Test paints for compatibility on a piece of scrap plastic before mixing different types or brands on your model. Also consider how the paint will be applied when selecting your finish.
Choosing the Application Method
Brushing and spraying are the basic methods of applying model paint. Enamel paints are the best for brush application. They dry slowly, allowing extra working time needed while brushing. Lacquer paints for plastic models generally come in spray cans, dictating the application method. Latex and acrylic paints can be applied with a brush or can be sprayed with an airbrush. Latex and acrylics can dry quickly, making brush application difficult. Use thinners or specially formulated extenders to slow the drying process to allow brush application. These paints also will require thinning for spraying from an airbrush. Each latex and acrylic manufacturer will have specific recommendations for thinning their paints for spraying.
Applying the Paint
Prepare the model for painting before beginning application. Wash the parts in warm soapy water, rinse well and air dry. Then apply primer or surface preparation solutions, as instructed by the manufacturer, prior to beginning paint application. A smooth finish can be achieved by brushing or spraying techniques. Protect areas that don't need paint with masking tape. Brush painting requires use of a clean, soft brush. Don't overlap brush strokes to prevent brush marks. Wide brushes are best for large open areas. Multiple, thin layers of paint, with fine sandpapering between layers, will yield the best finish. Spray painting can be performed with spray cans of lacquer or an airbrush for latex, acrylic or enamel paints. Follow manufacturer's recommendations for thinning paint for airbrush use. Keep the tip of the airbrush parallel to the surface when painting. Start the flow of paint before the model's surface is reached and end the flow after the tip of the airbrush is beyond the model. Apply multiple, thin coats of paint to avoid runs, wrinkles and "orange-peeling." Practice and patience are the best attributes for achieving a smooth, professional looking finish.
The Finishing Touches
Rubbing compounds, some especially formulated for plastic models, should be used to remove fine imperfections and scratches in paint. A matt, semigloss or gloss overspray finish can be applied to give a final patina to your model. Use Johnson's Future floor wax as a gloss clear coat to polish canopies and glossy body parts. Weathering is a special process that uses paints and pigments to simulate rust, dirt, grease and other effects, including rusting, fading and staining. The final appearance of your model is only limited by your imagination and the amount of time you dedicate to painting it.