Some also sell knives and related products. In other applications the edge must be as smooth as possible.ДЄ cook for railroad workers sharpens a knife on a stone wheel, in the fields of Western Australia, 1927ДЄs well as coarse grinding, sharpeners also typically 'dress' the cutting edges with a sharpening stone or honing steel, secure or replace loose handles and generally offer advice and assistance regarding best practice. For some applications an edge with a certain amount of jaggedness is acceptable, or even desirable, as this creates a serrated cutting edge. The extent to which this honing takes place depends upon the intended use of the tool or implement. This edge is then refined by honing until the blade is capable of cutting.

For example, the blade of a steel knife is ground to a bevel so that the two sides of the blade meet. Sharpening these implements can be expressed as the creation of two intersecting planes which produce an edge that is sharp enough to cut through the target material. Sharpening a straight edge is relatively simple, and can be done by using either a simple sharpening device which is very easy to use but will not produce the best possible results, or by the skillful use of oil or water grinding stones, grinding wheels, hones, etc. Knives, chisels, straight-edge razors, and scissors are examples. Many implements have a cutting edge which is essentially straight. The sharpness is measured at the microscopic level where the face of your implement may have an angle however at the convergence of the two angles is a joining point called the 'Apex'.ДЄ two-man team sharpen a knife at high speed For an extremely durable edge, a machete, chisel, drawknife or ax should be sharpened down to 30В° вЂ“ 40В° providing even more ruggedness and longer lasting sharpness. The less sharp angle means there is more metal there to cut, thus providing more durability out in the field. The sporting knife category, including pocket knives, survival knives, and hunting knives, sees more intense action and should be sharpened to the 25В° вЂ“ 30В° angle range.

This means care should be taken when handling these knives as they are susceptible to chipping and breaking. Japanese style knives utilize a much harder steel, and are therefore more brittle than their Western style counterparts. The exceptions are Japanese style knives that are usually sharpened to 14В° вЂ“ 16В° depending on the knife maker. Most kitchen knives, like utility/slicing knives, chefвЂ™s knives, boning knives, carving knives, should be sharpened to 15В° вЂ“ 25В°. Generally speaking, razors, paring knives, and fillet knives should be the sharpest knives at an angle of 12В° вЂ“ 18В°. Very sharp knives sharpen at about 10 dps (degrees per side) (which implies that the knife's edge has an included angle of 20-degrees). The disadvantage is that the sharpening angle is fixed so some specialized knives, like a Japanese style Santoku, may need additional attention to sharpen to the ideal angle. The main benefit of using an electric sharpener is speed with many models that can complete the sharpening process in one to two minutes. These electric sharpeners are typically used in the kitchen but have the ability to sharpen blades such as pocket or tactical knives. Several cutlery manufacturers now offer electric knife sharpeners with multiple stages with at least one grinding stage. The substance on the sharpening surface must be harder (hardness is measured on the Mohs scale) than the material being sharpened diamond is extremely hard, making diamond dust very effective for sharpening, though expensive less costly, but less hard, abrasives are available, such as synthetic and natural Japanese waterstones. A sharp edge may be 'dressed' using a Honing steel Modern synthetic grinding wheels and flat sharpening stones can be manufactured in precise grades of abrasiveness according to the intended process. The most traditional abrasive material is a natural stone such as sandstone or granite. This process also causes work hardening.ДЄn abrasive material may be rubbed against the cutting edge to be sharpened. Malleable metal surfaces such as bronze, iron and mild steel may be formed by beating or peening a flat surface into a sharp edge. A truly sharp edge is too thin to reflect significant light. Although this edge is sharp enough to bite a thumbnail, cut paper smoothly, or shave arm hair, the microscope plainly shows an edge which reflects light back into the lens. Edge/Apex of a knife after sharpening and stropping.

Craftsman drill sharpener