A sharp knife does better work more easily and safely. You can use an oilstone, a water stone or a diamond stone. Gizmo knife sharpeners are OK but ruin the edge over time by making it thicker. Here’s how to sharpen knives.
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1. The Burr
Until you have a burr — a wire edge that forms on the side of the blade opposite that which you are sharpening — you are not done sharpening that side of the edge. You may be able to see a burr. Or, feel for the burr by pulling your fingertips away from the edge — across the back of the blade, not toward the point or the heel.
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2. The Edge Bevel
Most kitchen knives have a 20-degree edge bevel. For filleting, an edge bevel of 12 to 15 degrees per side provides a clean, easy cut and reasonable resistance to dulling. If you don’t cut bone, monofilament or bait with your fillet knife, a 15-degree bevel will serve you fine.
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3. Set the Bevel
Divide the width of the blade at the heel by 5 to get the height above the stone needed to achieve a 12-degree bevel. If your knife is 0.75 inch wide at the heel, dividing 0.75 by 5 equals a spine height of 0.15 inches. Don’t like math? Stack two quarters, 0.07 inch each, to get the angle.
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4. Push or Pull?
It doesn’t matter. Iprefer to lead with the edge. Pulling, the edge is towards you; pushing, the edge is away from you.
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5. Sharpen It
Draw the blade across the stone, sweeping it from heel to tip as you go. Once you have a full-length burr, sharpen to create a burr on the other side. Finish with blade-first strokes, like slicing a sliver from the stone, until the burr disappears.