Angles
Very sharp knives sharpen at about 10 degrees (which implies that the knife's edge is a 20-degree angle). Typical knives are sharpened at 15 degrees. Knives that require a tough edge (such as those that chop) sharpen at 20 degrees or more. For an extremely durable edge (such as a chisel or drawknife), blades can be sharpened to 30 degrees.
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