Knives are sharpened by grinding against a hard
surface, typically stone. The smaller the angle between the blade
and stone, the sharper the knife will be, but the faster it will
dull. A guide is very helpful. Very sharp knives sharpen at 12-15
degrees. Typical knives sharpen at 22 degrees. Knives that chop
may sharpen at 25 degrees. In short, the harder the material to
be cut the higher the angle of the edge. The composition of the
stone affects the sharpness of the blade (finer grain produces
sharper blades), as does the composition of the blade (some metals
take/keep an edge better than others).
sharpening tools are the clamp-style systems, which use a clamp
with several holes with pre-defined angles. The stone is mounted
on a rod and is pulled through these holes, so that the angle
remains consistent. Another variant is the crock stick setup,
where two sticks are put into a plastic or wooden base to form
a V shape. When you pull a knife up the V, the angle is held for
you, as long as you hold the blade perpendicular to the base.
Remove a wire
edge (burr) if one forms during sharpening. Use a slighly steeper
angle with very light pressure to do so. If not removed, it will
break off in use, and the knife will instantly become dull. An
alternate method of removing a wire edge is stroking from side
to side on a very fine stone, using light strokes. This will flip
the burr back and forth as it is ground off.
To feel for
a wire edge, move your thumb lightly across the edge. It should
come off with no resistance. If you feel a little bit of pull
at the edge or the nail is sightly abraided, you may have a wire
stones are arkansas stones, which come in soft (coarse) and hard
(fine) varieties. These are traditionally used with water or honing
oil, but any oil compound, including olive oil, will do. India
stones are also similar to arkansas stones in function and end
are also used very often. Unlike natural stones, they will not
wear, and are very often used without any type of oil.
(both artificial and natural) come in very fine grits. They are
stored in water, and develop a layer of slurry which helps polish
off the edge. Generally, these are more costly than oilstones.
Needless to say, oil should not be used on these.
Oil is used
to lift the metal dust, called swarf, off the stone. This is usually
recommended for natural stones, but some say that detergent and
a brillo pad will have the same effect. Ceramic stones do not
need oil, they can be cleaned off with detergent. Diamond stones
should NOT be used with oil, rather, they can be washed off with
The best sharpening
stones are industrial diamonds embedded in plastic or metal. These
are more expensive, but still affordable. They cut about twice
as fast as other stones. Also popular, and rather expensive, are
sharpening blocks made from corundum.
a knife is an excellent finishing step. This is traditionally
done with a leather strap impregnated with abrasive compounds,
but can be done on paper, cardstock, or even cloth in a pinch.
It will not cut the edge significantly, but produces a very sharp
edge with very little metal loss. It is useful when a knife is
still sharp, but has lost that 'scary sharp' edge from use.
actually sharpening nor honing. All you are doing with a sharpening
steel is realigning the edge. Realigning the edge goes a long
way in keeping the knife sharp, as often times, a rolled edge
will make an otherwise sharp knife dull. There is no reason to
remove excess metal if the edge can be fixed with several strokes
on a sharpening steel.