From my experience as working around anodizing for the past couple years is sandblasting is something to stay away from when anodizing. Glass Bead blasting...Peening....gives you the results you need. Sand particles shatter and stick into the aluminum surface and can disrupt the durability of the coating, and also colored parts will come out akward and greyish in color, some will not take dye at all.
Quality Type 2 Anodizing PM me For a quote!
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