SharpeningVideo: 01:53

Description

For as long as people have been using knives, essentially since the stone age, a tool has been needed to sharpen them and keep them sharp. Basically, the tool used to sharpen needs to be harder than the knife itself. At the beginning, various particularly hard stones were used. At the end of the 19th century, file cutting factories started producing the first sharpening steels. To begin with, the teeth were cut into the blade by hand. Later on, special equipment was developed to produce sharpening steels faster and of consistent quality.

SHARPENING STEEL

Over time, the edge on a used knife goes dull. Although not visible to the naked eye, the blade's profile is no longer sharp but slightly rounded. This worn edge needs to be resharpened immediately on a sharpening steel. To sharpen a knife, pull the blade several times along the length of the steel, alternating between the left and right hand side of the knife's blade. It is important to make sure you perform the same amount of strokes on both sides. Hold the blade to the steel at an angle of 15° to 20°. Sharpen the edge little and often – before or after each use. Don't wait until you feel that the knife is no longer cutting properly!

Rapid Steel

If you do not want to use a classic sharpening steel, you can use a sharpening device such as Rapid Steel Action. This is how easily it works:
Slide the knife through the middle slot of the device quickly and in an arc motion, applying a small amount of pressure. This sharpens the entire knife in one go. Repeat several times. The result is a sharp knife with an optimal, pre-defined angle. Slide through easily and safely for a perfect edge.

SHARPENING STONE

Before using, place the stone in water for five to ten minutes. Ensure that the stone is always wet when in use as the dust released from the stone during the sharpening process should adhere to the stone and remain part of its mass. Begin with the coarse side of the stone. Applying a little pressure, slide the blade away from your body and back along the entire surface of the stone at an angle of about 15°. Begin at the blade's point. Repeat until fine burring appears. Then repeat on the other side of the blade. For optimal results and an extremely sharp, fine edge, repeat the above with the fine side of the stone. To remove the burring, slide the steel diagonally across the edge towards you. Finally, rinse the sharpening stone off and carefully clean your knife with mild dish detergent.

GRINDING MACHINE

Every time it is sharpened, the cutting angle on the knife becomes larger, and thus duller. Therefore, after having been regularly sharpened, the knife reaches the point where it needs to be reground on a suitable machine. It's difficult to say how often a knife generally needs to be resharpened as this depends on the demands placed on it. At the latest, a knife needs to be reground if it is no longer sliding effortlessly through foodstuff and regular sharpening just isn't cutting it any more.

When grinding a knife, the secret to getting the right level of sharpness is grinding at the correct angle. When grinding a chef's knife, we recommend using an RS-150 Duo machine, as the optimal grinding and honing angle has been set at the factory. Simply sliding the knife through the machine gives you a symmetrical grind and a knife which is sharp in seconds. Avoid using quickly moving, dry grinding belts as they heat the blade too strongly and strip the high quality steel of its hardness. Overheating changes the steel blade's microstructure, its corrosion resistance and its ability to keep its sharp edge. It could even cause tension cracks, which could lead to the blade breaking.