Sand Finish on Aluminum
My specialty metal shop is in the process of quoting a job to provide aluminum profiles coated with a sand-effect paint, both in color and texture. What paint do you recommend?
Q. My specialty metal shop is in the process of quoting a job to provide aluminum profiles coated with a sand-effect paint, both in color and texture. The paint must be scratch- and abrasion-resistant, but also low-cost and able to be applied by a standard air paint spray gun. What paint do you recommend, and do we need to apply a wash or any other chemical treatment to the aluminum to help with paint adhesion? R.C.
A. Two finishes come to mind for your products: residential wall finishes and skid-resistant floor finishes. Residential wall finish texture paints are available in a sand finish in a host of colors, and can be found in most paint stores. My only concern is their scratch and abrasion resistance. Skid-resistant floor finishes also are available in a sand finish, and because they are floor coatings, they have to be scratch- and abrasion-resistant. So I suggest you go to the industrial sales department at a paint company and ask for a scratch- and abrasion-resistant textured paint or a skid-resistant floor paint.
To ensure adhesion, the aluminum must be pretreated before painting. It is also important to remember that spray gun parts such as fluid tips, nozzles and fluid pumps that come in contact with the liquid paint will experience some wear caused by the abrasive particles in the paint. Some of the spray gun parts may have to be replaced more frequently.
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