Test Priming

Stopped by Southtown Auto/Napa and Canadian Tire today to pick up some test priming materials. Southtown was a good source of 3M scotchbrite and ProFrom professional paint supplies. I picked up a bunch of scotchbrite reloc pads and a reloc holder. I picked up a roll of aluminum from Canadian Tire as well as a can of Dupli-color Self Etching primer.

I begin with cutting up the aluminum into roughly 6" pieces. My first test was to see how the scotchbrite pads worked on the aluminum.  I used a 3" reloc scotchbrite wheel on the test aluminum, and it seemed to really scuff the aluminum with deep scratches. I immediately sensed that this is not the answer to prepping the aluminum. I then used some maroon scotchbrite hand pads to scuff the aluminum. Much better results. The surface preparation is more smooth and gentle. 

I cleaned one piece with MEK and one with the Proform Wax and Grease remover. I noticed that the MEK seems to evaporate quickly, while the degreaser/cleaner stays more wet. (Using an individual microfiber cloth for each, I wiped all excess liquid off and set them outside to dry for 20min (~23deg C and sunny). The Dupli-Color self etching primer was applied in two coats, the second being applied 10min after the first coat (as per the directions). The result is that after 45min dry time, both are easy to scratch with a fingernail (top right corner). After 3 hours the primer is becoming more hard, both are becoming difficult to scratch. It took a few tries and lots of pressure with the thumbnail to scratch the primer (top left corner).