The Best Way to Grind Aluminum
- 1). Attach a sanding disk of about 250-grit to your grinder. Test the grinder on a small piece of aluminum, to see the results before working on a larger area. Lubricate the aluminum with a kerosene-based polishing oil. Firmly secure the test piece with clamps, to prevent it from shifting as you grind it.
- 2). If the wheel looks as if it's getting gummed up from melting aluminum, add more lubricant and try again -- grinding at a slower speed. Once you are satisfied with the results, clamp the larger piece into place and lubricate the surface.
- 3). Move to a higher grit, once you have finished grinding with 250-grit. With every higher grit you use, remove all the marks from the previous grit. Achieve a nice, polished surface by finishing with 500-grit wet sandpaper. Mix some soap with the water and grind the surface, to remove any remaining marks.
- 4). Etch the aluminum using the grinder with grinding wheel attachments, as opposed to sanding disks. Use lubricant and avoid grinding at high speed, to keep the metal cool.
- 5). Grind hard-to-reach areas with a hand-held carver, using the same grit as you use for the angle-grinder.
- 6). Experiment with different types of grinding wheel attachments to see the effects. The type of grinding you desire will determine the attachments you need.
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