- 1). Slice two pieces of potato (skin and all). The size of the slices depends on the size of the knife. Make sure that you can cover both sides of the knife blade with the potato slices.
- 2). Wipe both sides of the knife blade with the potato slice. Concentrate heavily on the areas covered in rust.
- 3). Pour ½ cup baking soda into a bowl. Run the soft-bristled toothbrush under water, then dunk it into the baking soda so the bristles are well covered.
- 4). Scrub both sides of the knife blade with the toothbrush. The combination of the potato and baking soda should start removing the rust. Scrub thoroughly for a few minutes.
- 5). Wipe the knife blade with a paper towel, and examine the blade. Repeat the cleaning procedure until you no longer see rust on the blade. Clean the blade's surface with a paper towel.
- 6). Add ½ to 1 teaspoon of general purpose light oil onto both sides of the knife blade. Wipe both sides with a clean microfiber cloth.
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