How to Polish Diamond Plate
- 1). Clean the diamond plate with a hose or a power washer to remove dirt and debris and let the surface dry before you start. Purchase phosphoric acid from an automotive supply store in a spray bottle. Stock up on nylon scrubbing pads. Choose pads with a tightly twisted nylon surface. While scrubbing the diamond plate, you may go through many pads.
- 2). Put on the latex gloves and the protective eyewear before applying the phosphoric acid. Move the diamond plate over a gravel or dirt surface, since the acid will pit concrete if it drips.
- 3). Spray the diamond plate lightly with the phosphoric acid and let it sit for a minute or two before scrubbing the metal with the nylon pads. Rub in one diagonal direction and then in the opposite to make sure all the little treads are cleaned of residue. Do a small inconspicuous section before moving on to a larger portion.
- 4). Notice that the diamond plate takes on a whitish cast. This is fine for most diamond plate surfaces but if your diamond plate has an extra clear coat, use a paint polish instead of the phosphoric acid.
- 5). Repeat the application process of the acid until all the residue dissolves before spraying off the diamond plate with water and wiping it dry. It may still have a white cast to it but now we’re going to use polish to clear that up.
- 6
Choose a quality metal polish. Most automotive supply stores do not carry commercial grade polish but you can often find it where truck drivers stop. When you want to restore the factory shine to diamond plate, you need a quality product. Some truck drivers suggest Busch’s Super Shine Aluminum Polish for the best results (see Resources below). - 7). Apply the polish as indicated on the product’s label and wipe off with clean soft rags. For a shinier finish, try using a soft wool buffer and buff the diamond plate in a circular motion until the surface is smooth and shiny.
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