We recently took a contract with a company that builds amusement parks. In this particular contract, we were asked to paint the aluminum bumper rails of a mini golf course. The customer was to supply PPG’s Durethane in a custom color. Durethane is a self-priming, mastic urethane that we assumed would be a great fit for the aluminum rails, but we did not anticipate any issues with adhesion.
After receiving the 53, 25 foot long, aluminum bumper rails we noticed that the aluminum had a surface that resembled a mirror. They also had a little bit of oil on them, we had expected that and put cleaning with solvent into our proposal. We did not anticipate that these rails would be as smooth as glass once they were cleaned, though. So we went to work, testing the adhesion.
We tested the adhesion with the Cross Cut method. We made sure to use 3 separate profiles on the surface of the aluminum- not cleaned, cleaned, and abraded with sandpaper then cleaned. We painted the test surfaces and came back the next morning. We then sliced into each of the test areas using the cross cut method- making a shape with the knife that resembled a complicated game of tic-tac-toe. Then we tried to peel the paint away from the surface of the metal. Both the not cleaned and cleaned with solvent areas failed with ease. The abraded and cleaned section, on the other hand, held up perfectly.
So we sanded the areas all down and removed the paint, and went to work abrading and cleaning each piece of aluminum. The process took a couple of hours longer, but I can guarantee that our customer will be happy with the finished product and the people that play their game of putt putt will be amazed at how beautifully their bumper rails were coated. You’re welcome mini golf players.