Yellow Chromate Surface Preparation
- 1). Clean all surfaces thoroughly with solvent to remove obvious oil and grease, and air dry.
- 2). Sandblast all surfaces with clean silica or aluminum oxide abrasive. Grind heavy plate surfaces with 24-grit rigid discs.
- 3). Grind all weld beads to eliminate scale and expose pores. Re-weld and regrind all pores using an MIG (Metal Inert Gas -- for ferrous metals and some alloys) or TIG (Tungsten Inert Gas -- for aluminum and other alloys) welder and a grinder.
- 4). Immerse or coat aluminum surfaces with a non-flammable phosphoric acid-based cleaner. Wash the cleaner off the surface with water after two minutes.
- 5). Spray prepared aluminum surfaces with water before painting or plating. Water will not bead on a properly prepared surface. Degrease the surface again if water beads.
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