2. Here is the milling process as it is happening. You can see the machine cuts the design in the aluminum, using a blue liquid as a coolant. From here, the piece is taken to the polishing station to receive a quick deburr and a complete polishing. No matter what finish you order, whether polished, brushed, or powdercoated, the aluminum is still polished and then either brushed or sent out for powdercoating.