I have some parts that I am facing off in a cnc machine. Its the top of some 1/2" places that are about 6" x 1". These are cosmetic pieces and I have them anodized type III hard coat black for the customer. I have to tumble the parts for a very long time before sending it to anodizing and there are still some swirls you can see behind the anodizing. Is there like a wire cup brush that I can use to chuck in a holder and run it across the top to smooth out the finish?

I was looking at buying some brass wire cup 2" brushes but didnt know if they would be to rough on the surface. I know they make brushes in nylon, stainless steel, brass, aluminum, etc. I can take a scotchbrite and scuff it for about 2 mins and almost get them out. What is the best to use on aluminum for a smooth finish?