The majority of industrial paints are designed for easy application to ferrous and non-ferrous metal surfaces. Iron, steel, aluminum, tin, and galvanized substrates all require slightly different methods of preparation. You should be sure to familiarize yourself with these methods before applying industrial paint on your next project.
Steel is one of the easiest metal surfaces to paint. Before beginning any paint job, you should always ensure that all rust, grease, debris, and other foreign detrimental matter are removed. The object to be painted should be brought down to the bare metal. This can be accomplished through hand or power tool cleaning, solvent degreasing, or sandblasting. Fine grit sandpaper can also be used. An Industrial Paint etching primer may be used, although these have decreased in popularity in recent years because of their ineffectiveness. Most general purpose industrial primers will exhibit excellent adhesion (whether self-etching or not) so long as the surface is properly prepared to receive the coating. Prior to laying down the topcoat paint, some users prefer to sand the now-primed object to ensure that they have the smoothest substrate possible for their topcoat.
Aluminum can sometimes be a difficult metal to paint. To best prepare an aluminum surface for painting, an acid wash or degreaser is often employed to etch the surface. Once the surface is etched, paint will flow into the miniature fissures created by the wash and provide superior adhesion.
Plastics and acrylics can generally be painted with an industrial coating, but may respond differently to certain products, depending on the solvents used in a given product formulation. Water-reducible coatings are often the best choice for these surfaces, as they are not likely to cause damage to the object being painted. The use of a primer is very important when painting acrylics, as it blocks light from filtering through the material and increases the hide of your finish coat. The semi-transparent properties of certain acrylics can be most noticeable when they are painted with bright colors – which traditionally have poor hiding due to the nature of their pigments. A thick coat of primer will provide better adhesion for the topcoat, while virtually eliminating any filtered light that might come through the acrylic substrate. As is the case with most plastic and acrylic coating projects, it is highly recommended that you apply your coating in a “test spot”, to determine its effectiveness and rule out any possible compatibility issues with the object.