The classic image of knife sharpening might be one of a chef artfully honing his blades on a whetstone, a literal rock soaked in water. Sharpening Angles Discussion of edge angles is where knife sharpening starts to seem complicated. The more advanced knife sharpening tools will usually accommodate multiple sharpening angles for different types of knives. If you’re not sure what angle your knife was built with, most manufacturers will list the edge angle of a knife in their online product descriptions. However, both beginners and knife aficionados who want a consistently sharp edge will appreciate the Precision Adjust knife sharpener.