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Honing
and Sharpening Knives
There are three types of
metal alloy used in high quality cutlery today: ( 1)
all carbon steel, (2) high carbon stainless steel, sometimes
called "no-stain steel," and (3) very high carbon
stainless steel. All carbon steel is the softest, and
very high carbon stainless steel is the hardest. In
the middle is high carbon stainless steel.
All carbon steel was used for
years in the making of cutlery. The problem is that it
rusts and stains readily.
All carbon steel and high
carbon stainless steel have the same basic amount of
carbon: .45% to .5%. The carbon gives the steel
hardness. The more carbon, the harder the knife
metal. The difference between two metals is chromium,
molybdenum, and vanadium, which give stainless steel its
stainless qualities. They also give the steel
added compression hardness and tensile strength. Knife
stainless steel has 13% to 14% chromium, and about 1%
molybdenum and vanadium together.
German knife producers
pioneered the high carbon stainless steel so that a knife's
metal would be (a) hard enough to hold an edge, (b)
flexible, (c) soft enough to hone and sharpen, and (d)
resist rust and corrosion. The formula for German
stainless steel is as follows:
X 45 Cr Mo V 15
or X 50 Cr Mo V 15
X
means stainless.
45 or 50 means .45%
or .50% carbon.
Cr Mo V means the total
percentage of chromium, molybdenum, and vanadium, namely
15%.
Shun,
Global
and MAC
knives are made from very high carbon stainless steel (1%
carbon) with three times the amount of molybdenum as German
cutlery (3% molybdenum).
What is the difference
between honing and sharpening? When a typical knife is
sharpened, it has tiny microscopic teeth all along the
cutting edge. When the knife is used, the teeth and
edge gradually flatten out. A honing steel, which
looks like a short sword with a round blade, is used to draw
those teeth and the metal of the cutting edge back into
shape so the edge is keen. The honing steel is
not designed to remove metal. If used aggressively, it
will do that, but that is not its primary function. A
good steel is magnetized to help in drawing the cutting edge
back into shape.
Sharpening is removing metal
from the cutting edge to remake the edge. The most
common sharpening device used to be a whetstone. Now
diamond and ceramic rods are available and widely used.
Honing steels are most apt
for carbon steel knives, because they are soft and the metal
edge blunts readily. Prior to no-stain steel, a
butcher or chef would use a steel often in a day to realign
a knife's edge. However, with the advent of the harder
no-stain steel, the edge of a knife stayed sharp longer,
thus not needing honing as frequently. Moreover, the
typical honing steel was not as effective in realigning an
edge when it dulled. The honing steel itself had to be
made harder.
F.
Dick is the leading manufacturer of honing steels which
are hard enough to handle no-stain steel, and make the
broadest selection.
How is
a knife honed?
The best and safest way is to
hold the honing steel straight up and down, the handle up
and the tip down, the tip anchored on a cutting board.
Take the knife with your other hand. Place the back edge
blade against the steel near the top of the steel at a 20
degree angle. Now draw the knife towards you and at
the same time down the steel shaft toward the cutting
board. Use a light touch; do not grind the
blade! Then shift the knife to the other side of the
steel shaft and repeat. Repeat until you are
happy with the edge.
Control of Sharpening Angle
It will take practice to
simultaneously control the sharpening angle while stroking
the edge along and across the sharpening steel.
Since the edge angle of knives
varies widely from one brand to another and sometimes
between blades of the same manufacturer, the correct
sharpening angle for each blade must be established by trial
and error.
Start steeling with an angle of
approximately 20 degrees, which is really a very small angle
(see figure). An angle of 45 degrees (half way to a
perpendicular angle) is too large. If you can imagine
a 45 degree angle and then cut that in half you will have 22
1/2 degrees. That will be about the right angle to
start with. Stop steeling after a few strokes and
inspect along the edge to see whether your sharpening marks
are primarily along the edge or along the shoulder of the
edge.
Why
oval and flat steels? They put more metal in
contact with the knife edge per stroke and thus hasten the
honing process.
There is one exception to the rule that honing steels do not
sharpen a knife. It is the F.
Dick Multicut Steel. It has deep grooves
running the length of the steel. When a knife blade is
pressed hard against the steel it will take off metal and
sharpen it. F. Dick claims it will do sharpen faster
that a whetstone. When a knife blade is pressed
lightly against the steel, it will hone it.
Do not try to hone a Global,
MAC
or Shun
knife with a regular chrome steel; the metal is too hard.
Use a diamond or ceramic sharpening rod or system. Diamonds and ceramic
are harder than steel.
To sharpen a knife, use the
same process with a diamond or ceramic sharpening rod or a
similar process with a whetstone. Hold the whetstone flat and the
knife at a 20 degree angle. Draw across the stone, or use a
circular motion, with pressure as you move the knife blade
into the stone and none as the blade circles away from the
stone. Use a light touch.
F.
Dick Diamond Rod
If you have very dull knives
or little patience, I can recommend the Chef'sChoice
Electric Knife Sharpener. It is very fast
and will create a durable, extremely sharp edge in seconds.
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