Getting Ready to Buff :
Aluminum polishing, conditioning and smoothing

The key to that satisfying gleam is knowing where to start and understanding the difference between polishing and buffing. Often novices use the terms interchangeably. Polishing removes a heavy amount of material, like during sanding or grinding. Buffing is the process that brings out the actual full brilliance of a part. Parts with dented or scratched surfaces will first require some conditioning before buffing can be effective. Let's see how to prepare parts for buffing.

An aluminum trim is a perfect example since it is almost never in a ready to buff state. Scratches and dings may be removed in a similar manner to dents on a car body, only on a smaller scale. Use a Mini Anvil and Trim Hammer to raise the dent. Blows of the hammer spiral in toward the center to minimize stretching.

Once the surface is relatively straight there are five aluminum polishing and smoothing methods prior to buffing. The most time consuming is to block sand or file the part by hand, allowing for the greatest control. An expander wheel used at up to 2400 rpm with premium grade 3-M Trizact Abrasive Bands will also level the surface and maintain the flatness of the surface without rounding edges. This band serves the same purpose as regular abrasive bands except it's available in finer grits and cuts more consistently throughout its longer life. Trizact Bands can be used to get relatively flat surfaces smoother quicker than any other abrasive reducing buffing time. Scotch-Brite Bands are also for use on the expander wheel, but due to their mesh-like construction work better on slightly contoured surfaces. Edge marks on the part are virtually eliminated due to the softer construction of these bands.

For aluminum polishing and smoothing of highly contoured surfaces, a greaseless compound (13129, 31, 32, 94) is the most effective. These compounds are applied to either or Spiral Sewn or Loose buffing wheels. Available in 80, 120, 220, and 320 grit, they convert your buff into a flexible grinding wheel.

Aluminum polishing and smooting of tight access areas can be made easier with abrasive rolls, available in cylinder and tapered formats from 80 through 320 grit. They are used on tapered mandrels ranging in length from 2 ¾" - 6". Use the shortest mandrel possible since excessive side loading will more easily bend the longer mandrels. Felt bobs used with greaseless compounds mentioned above act as another alternative to using abrasive rolls.

Vibratory Tumbler Systems for aluminum polishing and smoothing

Vibratory tumbler systems can be used for aluminum polishing and buffing (small parts), and is an effective alternative to hand finishing. The vibratory type of tumbler works up to 25 times faster than rotating tumblers. Actual process time will vary from a few hours to a few days depending on the condition of the parts and the finish desired. Parts to be tumbled should be free of grease, oil residues and paint coatings. The tumbler load should consist of 30% parts to 70% media, without exceeding the maximum rated tumbler load of approx. 3 lbs for the small tumbler and 6 lbs for the large tumbler. The pyramid shaped Green Rust Cutting Media is used both in the smaller bowl for the small tumbler or the single heavy-duty bowl included with the larger tumbler. Add enough water to just cover the media without creating standing pools of water. It usually takes between 5-12 hours to de-rust and clean moderately rusty parts. If a high shine is desired, the parts can then be placed in the bowl with the Dry Shine. This media will impart a high luster in 24 hours to a few days.