Started cleaning bottom of step ribs, seat rib flanges, baggage floor rib flanges, and bulkhead flanges. Cleaning accomplished by rubbing affected areas with rags soaked in Acetone to remove primer. As required, used stiff nylon brush and Acetone to get into corners. Scrubbed corrosion areas with Scotch Brite pad soaked in Acetone (did a real good job removing corrosion). Still need to treat raw aluminum with Alumiprep 33, Alodine 1201, and prime.
Had an independent A&P stop by to inspect progress and critique approach. He said that what I'm doing is good and that I shouldn't have any long term issues. Best to appropriately address all areas now instead of dealing with it later. He mentioned that there is an Alodine pen that can be used on the rib flanges that can be applied and let it dry (no rinsing and drying). Found Bonderite M-CR 1132 (Alodine 1132) online and bought one. Very pricey (about $100!) but should be easier to apply once I'm ready to treat flanges.
