It is crucial to understand that most coating failures are actually problems with adhesion to the substrate as a result of poor surface preparation. Conversely, when proper surface preparation steps are followed religiously, the full benefits of the finest chemical coating systems can be fully realized.
This means that only bare substrates should be coated. They must be completely free of every last bit of residue of past coatings, paints, varnishes, corrosion inhibitors, etc. As would be expected, different substrates require slightly different preparation processes.
Steel & Stainless Steel Substrates:
Old paints can be removed using chemical-based paint removers. Surfaces should then be grit blasted to bare metal using our aluminum oxide grit blast media. This assures total cleanliness and provides a “tooth” for maximized adhesion.
Aluminum Alloys:
As with steel substrates, old paints or coatings can be removed with an appropriate chemical-based paint remover. Large surfaces can be sanded with a jitterbug to remove all traces of oxidation. Smaller surfaces can be bead blasted with our glass bead blast media.
This cleaning must be immediately followed with an acid etch primer layer. This is a chemically-compatible, micro-thin layer that acts like a conversion coating. It is easy and fast to apply and prevents the rapid re-oxidation that aluminum alloys are so famous for while the epoxy primer step is prepared.
Magnesium Alloys:
This preparation is similar to that of aluminum but without the application of the acid etch primer.
Composites:
Existing paint, if any, must be removed using an appropriate paint remover. Care must be exercised in selection of the remover chemical. Composites such as carbon fiber are comprised of an epoxy matrix which can be attacked by some of the more aggressive paint remover compounds. All gloss must be removed from the epoxy surfaces to assure a good adhesion surface.
