Things You'll Need
Professional sharpening kit
Maintaining and sharpening a bowie knife presents a challenge even to people experienced with knives. The blade of a bowie knife has a distinct curvature at the end and can reach lengths up to one foot. Bowie knives require regular sharpening. You can sharpen it using a whetstone or commercial sharpening kit.
Inspect the angle of your edge. When you sharpen a bowie knife, duplicate the angle as closely as possible. If necessary, use a professional sharpener. It will have angle increments.
Place the blade of the bowie knife on the whetstone (if using one) at the appropriate angle. Prior to sharpening the knife, ensure that your whetstone has been lubricated with the appropriate solution. Failing to do so could destroy your knife's edge.
Exert pressure on the knife as if cutting into the whetstone and draw it along the stone from hilt to tip, with the edge facing away from you. According to Hunting Expeditions (reference 1), straight passes along the stone prevent damage to the knife's bevel.
Flip the blade over, inspect its angle and sharpen. Make two passes per side, then switch sides and repeat. This ensures that your edge will be even on both sides. Periodically test your knife's edge by cutting through a piece of paper. If the paper does not crumple, your knife is properly sharpened. Over-sharpening a bowie knife can make the edge brittle.
Wash the whetstone off with dishwashing fluid and put the knife away.