Paint is any liquid, liquefiable, or mastic composition which, after application to a subtract thin layer, is converted to a solid film.

Paint manufacturers continue to modify paint formulas, but there are four basic types of materials that make up any paint.SolventResinsPigmentAdditives

This is the liquid that carries the solid components of paint.The term SOLVENT is used frequently to include liquids that do not dissolve the polymeric resin.

The binder or resin is one of the most important components of paint. It is the basic solid film former that remains after the solvent has evaporated and which binds the pigment particles together into a cohesive paint film.

This is the component that gives paint its other most important properties of color and opacity. The pigments used in paint are normally present as fine solid particles that are dispersed, but not soluble, in the binder and solvent.

Additives are the special components of paint, they are used in small quantities to improve production and storage properties of the liquid paint product as well as application and other performance properties of the paint film.

Paint application seems to be one of those more difficult areas of modeling to master.  While a lot of great tips, advice, and techniques show up here on the Board, troubleshooting paint problems, sight unseen, is still pretty difficult.

Accumulation of dirt, dust and/or other debris on the paint film; may resemble mildew.

Use of low-quality paintsSoil splashing onto sidingAir pollution, car exhaust and airborne dust collecting on house body and trim

If unsure whether the problem is dirt or mildew, conduct a simple spot-test with bleach.

Remove dirt with a scrub brush and detergent solution, followed by thorough rinsing with a garden hose.

Paint with a high-quality paint that is formulated to provide superior dirt pick-up resistance.

A formation on the finish of pigment powder that is no longer held by the binder, producing a dull look

CAUSES: Wrong thinner or reducer affecting topcoat durability.Poorly mixed materials.Paint film too thin. Excessive mist coats when finishing or refinishing metallic color applications.SOLUTION:Select the thinner or reducer that is best suited for existing shop conditions. Stir all pigmented undercoats and topcoats thoroughly. Meet or slightly exceed minimum film thickness

specification.

Bubbles or pimples that appear in the topcoat film, sometimes months after application.

CAUSES: When temperature or atmospheric pressure increases, the moisture expands and builds up pressure, resulting in blisters. Wrong thinner or reducer. Contamination of compressed air lines with oil, water or dirt.SOLUTION:Thoroughly clean the areas to be painted before

and after sanding. Select the thinner or reducer most suitable for existing shop conditions. Drain and clean air pressure regulator and drain air compressor tank daily.

Dimpled surface, like the skin of an orange, resulting from paint droplets drying too much to level out and flow smoothly together (poor coalescence)

CAUSES: Improper gun adjustment and techniques. Improper drying by gun fanning causing the paint droplets to dry out before they have a chance to flow together.. Wrong thinner or reducer, or too little thinner or reducer.SOLUTION:

Use proper gun adjustments, techniques, and air pressure.Allow sufficient flash time. Do not dry by fanning. Allow proper dry time for undercoats and topcoats. Mix all pigmented coatings thoroughly.