Abrasive Blasting & Airless Spraying of Sewer Gate at North Head WWTP using Blast It Clean It Paint It Graco King 68:1 Airless Sprayer. The Sewer Gate was abrasive blasted to Sa 2.5 with Garnet then primed & topcoated using the Airless Sprayer. Akzo Nobel (International Paints) were specified for this Sydney Water project.