The factory made edge on any new knife starts to dull as soon as you put the knife to use. As a result, the sharpness of your kitchen knives depends very much on how you maintain them. There are two basic maintenance methods: regular straightening and conditioning of the edge, known as honing; and after a while, creating a brand new, sharper edge. Knowing when to sharpen versus when to hone is a simple matter. If you can no longer restore the edge with a steel, the blade needs to be sharpened.
Honing
A sharpening steel is a metal rod with a finely ridged surface. Despite the name, a sharpening steel does not sharpen a knife as much as it resets, or realigns, the edge. Under a microscope, a dulled edge appears to have misaligned teeth, which catch as you cut. Ten strokes on each side of a steel are usually enough to reset the knife edge before using it again.
A fine steel produces a smother finish, though honing is faster on coarse steel. Any steel can be used horizontally or vertically. Here's how:
If steeling vertically, anchor the steel in a damp towel, then place the heel edge of the knife behind the steel at a 20 degree angle. Pull the entire blade down the length of the steel until you reach the tip, then place the knife in front of the steel and repeat.
To steel a knife horizontally, hold the knife in the cutting hand with its blade perpendicular to the steel, which is held in the other hand. Find a 20 degree angle, and move the knife across the steel from heel to tip. Turn the knife over and repeat. Ten strokes on each side are usually sufficient.
There is no need to use a lot of force or to work quickly. And since the steel does not remove much metal from the blade, you need not worry about overdoing it. After you finish honing the blade, wipe it dry to remove any clinging metal particles. Since a steel is magnetized to attract particles, store the steel separately from knives.
Sharpening
Keep in mind that you can actually damage your knives if you try to sharpen them at home without being sure of your technique. If in doubt, have your knives professionally sharpened. Check the Yellow Pages for knife sharpeners, or try hardware stores or sporting goods stores. Beware of sharpeners that heat the knife to a point at which it throws off sparks. This can actually remove too much metal, and reverse the tempering process that lends the knife hardness. Once a knife is distempered, it will no longer take or hold a sharp edge.
A knife can be sharpened several times a year on a stone. A rectangular Carborundum block with medium coarse and medium fine grit is most common for home use. Before using, cushion the stone in a damp towel, lubricate it with food grade mineral oil, and orient it vertically. Start with the coarse side up; lay the heel of the blade on the bottom right hand edge of the stone. Sharpen the entire edge by holding the knife at 20 degrees with one hand while guiding the blade with the other. Turn the knife over, repeat, starting with the heel of the blade on the lower left hand edge of the stone. After ten to twenty swipes on each side, use the fine grain side to hone the edge.
