Introduction
Spray Finishing
Today's paints and coatings are more complicated than the finishes of 10 to 20 years ago. New products were developed for regulatory compliance and market needs.
These new coatings come in a variety of chemistries: Polyurethane, Acrylic, Epoxy, and Poly-Aspartic. The chemistries can also be formulated as solvent based or water based systems. These coatings are generally higher in viscosity, solids, and cost than past systems. This change in properties has prompted improvements in spray application methods.
Greater Efficiency
Higher material costs prompted the need for better transfer efficiency / less wasted paint. Improvements to application technologies came along with new formulations. More paint on the surface being painted and less overspray. Conventional siphon guns required high air pressure to pull materials through the spray gun. The high pressure created excessive overspray of atomized paint. Newer designs are fluid or gravity fed to lower the air pressure.
High solids and waterborne coatings also dry slower, but required fewer coats than traditional low solids materials. The new coatings were applied in fewer, thicker coats, which compensated for the slower dry times. Each method has it's advantages and disadvantages.
