New aluminium items have a deep polish on their finishes that reflects much like a mirror. Wheels, motorcycle parts, bumpers or any other aluminium becomes dull over time and may acquire pits from the weather. Dremel makes handheld rotary tools with attachments that are effective at polishing dulled surfaces. Start by using the Dremel to give a thorough sanding of the aluminium with heavy grit paper and working toward a fine grit paper to remove pits and small scratches. This creates a smooth surface for polishing.
Unplug your Dremel from the electrical socket if you have a model with a cord.
Press and hold the shaft lock button on the top of the shaft near the collet. The collet is a round metal nut that holds the Dremel attachments in the tool.
Turn the tip in the Dremel clockwise by hand until it will no longer move. Place the collet wrench over the collet nut and turn counterclockwise to loosen it.
Slide a 60-grit sanding drum into the collet and turn the collet wrench clockwise to tighten fully.
Plug the Dremel into an electrical socket.
Hold the Dremel as you would a pencil among your thumb, forefinger and middle finger, on the indention near the tip of the shaft. Turn the Dremel to the low speed setting, or 5,000rpm on a variable speed Dremel. Slide the “On/Off” button to the “On” position.
Pass the Dremel over the aluminium object in slow strokes from side to side, making certain to sand all areas of the metal.
Turn the Dremel off and unplug a model with a cord. Loosen the collet and slide a 120-grit sanding band onto the sanding drum.
Repeat the sanding process in the same manner. Remove the sanding drum and band, replace them with a 180-grit sanding disk, then a 220-grit disk and finally a 240-grit disk to finish sanding. Wipe the aluminium with a dry washcloth to remove any particles.
Place a polishing wheel in the Dremel and tighten it completely. Place the Dremel tip in a can of polishing rouge to apply the rouge to the polishing wheel.
Polish the aluminium in the same manner as you sanded. Apply more polishing rouge as needed to obtain a high-gloss mirror finish on the aluminium.
The repetitive sanding creates an extremely smooth aluminium product to accept the polish for a mirror finish.
Do not press down on aluminium with the Dremel tip. The tool will work on its own without pressure from an operator. Pressing down hard can bend, break or destroy a Dremel accessory. Make certain that the collet is tight on each Dremel accessory. A loose collet allows the tips to wobble in the collet, or they can fall out and make indentations on aluminium projects.