A PRIMER ON KNIFE SHARPENING - Chapter 2
by Steve Bottorff
color photographs by Carol Butz
CONTENTS
CROCK
STICKS
Ceramic rod sharpeners, also known as
crock sticks, are completely different than bench stones. The rods are
held in a vee at a predetermined angle, and the blade is brought down
against them in a slicing motion. You can manually make deviations from
the set angle by tilting the blade.
Unfortunately most of these
sharpeners come with only one grade of rods so they have limited use. An
exception is the Tri-angle Sharpmaker from Spyderco. Their deluxe set
comes with two pairs of ceramic rods, medium and fine, and a pair of
medium diamond sleeves for pre-sharpening. A fishhook groove, a scissors
position and a flat position extend the Tri-angle Sharpmaker for special
uses. The Tri-angle Sharpmaker comes with a good instruction book.
Lansky makes a handy folding ceramic
rod sharpener called Fold-A-Vee. It folds for easy carrying and
features two angle settings for fillet and hunting knives.
SLOT
GADGETS
There are a whole lot of gadgets on
the market that promise easy sharpening. I have tried a lot of them in my
quest. Theoretically with slot-type gadgets you just draw the knife
through a slot a few times and it will be sharp. Many are worthless
gimmicks, but some are worth considering.
The most primitive type of slot
gadgets uses a pair of tungsten carbide tool inserts set at an
angle. A variation uses a set of overlapping carbide wheels.
These literally scrape metal away from the edge, and leave a sharp, but
somewhat ragged, edge. This type shapes the initial bevel but
provides no way to hone or steel the edge. I bought one and it ended
up in my junk box. Benefit from my experience and save your money.
More refined slot gadgets use two
sets of ceramic wheels or rods, one medium and one fine. This type hones
well but is limited in its ability to sharpen. In the TwinSharp from J. A.
Henckels these wheels are in the same slot. In theory you might use
both in one pass, but in practice I found that changing your hand position
changes which set of wheels contacts the blade. Knowing this, you
can sharpen and hone separately. The TwinSharp is handy for
touch-ups and I used it between regular sharpenings until I gave it to a
friend.

The FireStone 1302 Knife Sharpener
from McGowan Manufacturing is also a two stage setup, but with sets of
four interleaved medium and fine wheels, each set in its own slot.
This makes it more convenient if the knife needs more sharpening than
honing or vice versa. The Firestone would be especially handy if you
own their electric sharpener, reviewed below. McGowan also makes a
variety of other manual sharpeners marketed to fishermen and bow-and-arrow
hunters. These feature additional tools like a broadhead wrench,
fishhook sharpener and line cutter. Like golf spike tools and
shotgun choke removers that are often featured on specialty knives, these
tools are indispensable when you need one. I picked up a FireStone
SharpPocket because it was winner of a product design competition.
This is a single stage sharpener with only medium grit ceramic
wheels. Instructions say to go light on the last few strokes to
polish the edge. In my opinion the ceramic wheels are too coarse for
a good edge, and they wobble. It has joined my junk sharpener
collection.
If you are going to benefit from a
slot gadget, it must hone at an equal or greater angle than your
sharpening. The Chef'sChoice Model 450 uses diamond stones at the same
angles (22.5 and 25 degrees) as the final two stages of their electric
sharpeners. I keep one in a kitchen drawer for use between regular
sharpenings on my Chef'sChoice Model 110.

For about $2, the Normark sharpener is a best buy.
The Normark knife sharpener is an
inexpensive slot gadget that can be found at a sporting goods store next
to Normark's fillet knives. It has two sets of ceramic rods set at
20 degrees. The medium gray rods sharpen and the fine white rods
hone. I have used it to restore a slightly dull blade to shaving
sharpness. It costs about $2, so it surely is the Best Buy. The
Normark's 20 degrees is perfect for touching up a fillet knife where the
initial edge was 17 or 18 degrees.
There is one class act in every
category, and the Meyerco Sharpen-It is it for slot gadgets.
Designed by Blackie Collins to be so simple that it could be used on
horseback, the Sharpen-It features tungsten carbide wheels for the first
stage and fine ceramic wheels for the second. The ceramic is so hard
and fine-grained that it is more like using a steel. With this
combination, the Sharpen-It performs well at both sharpening and honing.
Unlike other slot devices, the
Sharpen-It adds a third wheel to each set, giving two slots, and shapes
them so that they sharpen one side of the blade at a time. This
setup allows you to vary the bevel angle somewhat. Drawing the knife
through at an angle decreases the bevel angle and gives a more razor-like
edge. Since it is assembled with tamper-proof screws, I could not measure
the bevel angles, but this information is less important because you won't
have to use it with another sharpener to get complete results.
Also unlike others, the Sharpen-It
can be used equally well left-handed. It is so compact when closed
that it can be carried in the watch pocket of your jeans. The unit
well built and sturdy, and features a tapered hone for serrated
blades. A less expensive model is available without the tapered
hone.
ELECTRIC
SHARPENING MACHINES FOR HOME USE
Cheap electric knife sharpeners such
as those found on can openers grind aggressively but with little control
of angle or depth. I've seen many knives ruined by them and they have
given electric sharpeners a bad reputation. Here are two electric
sharpeners worth considering for household use.
The FireStone Diamond Electric
sharpener from McGowan is a fast machine that produces a toothy,
aggressive edge with just a hint of a burr. I prefer a more refined edge
and the Firestone manual sharpener reviewed above is just the tool to
refine it. The instructions don't say so, but the designer recommends
pulling the knife through the wheels a few times with the machine turned
off to align the edge, effectively using it as a manual sharpener.
But this edge, right from the machine, will slice right through a ripe
tomato while a fine edge may not.
The manufacturer specifies 23-degree
bevels on all their FireStone sharpeners, but I measured 18 to 19 degrees
on the electric sharpener and 21 to 22 degrees on the manual sharpeners.
The18-degree hollow ground edge would be another reason for the aggressive
cutting. The FireStone manual sharpener would hone it to a
longer-lasting angle.
Note: there is no generally accepted
method for measuring bevel angle of hollow ground blades. I like to
measure the wheel diameters and spacing and calculate the angle at the
edge by trigonometry. This manufacturer suggests measuring the
average angle of the entire bevel, but that varies with blade
thickness. My low number is the angle at the edge, and my higher
number is the average angle for a blade with 0.020 thickness at the back
of the bevel, typical of a hunting knife.

The FireStone design features four
interleaved, counter-rotating wheels like commercial machines, but without
the adjustable angles that make the commercial machines so
expensive. The wheels are 220 grit diamond-impregnated
ceramic. I found it difficult to sharpen close to the bolster with
the FireStone electric sharpener and, because it grinds so fast, you
cannot play around much without grinding a swale into the blade. The
instructions say you might need up to 10 passes on a new blade, but I
found that every blade I tried was sharpened in a single pass and begin to
show loss after only 3 passes. I suspect that repeated use of this
sharpener would reduce knife life or require professional sharpening to
re-shape the blade. I would prefer that this sharpener used finer
stones and a slower speed.
McGowan
has updated the Firestone electric sharpener. It is now called the
DiamondStone and comes with finer stones. My few uses of it
indicate it works as well as the Firestone and produces a better edge.

The Chef'sChoice 110 features three sets of diamond hones, and does a
great job of sharpening.
EdgeCraft's Chef'sChoice Model 110
uses 3 sets of diamond hones and each sharpens at a different angle. The
first stage is very aggressive, grinding even faster than the FireStone,
but it is only used once to pre-shape the bevel. From then on you
use the second and third stages (sharpening and honing) only. The
final honing is at a very sturdy 25 degrees, which will give very long
edge life. (The Model 310 is similar, but with only the final two
stages. I have not used one.)
The Chef'sChoice is my recommendation
in this class, with one caution - it has a tendency to scratch the sides
of a blade, so I can't recommend it for collectible knives, but it is
great for working knives.
The
latest Chef'sChoice sharpener is the model 130. It is identical
to the 120 except the second stage has been replaced with a steel,
giving you the option of having a steeled edge without mastering
steeling. Guides make the task foolproof, and the steel segment
is threaded so that as the small section you are using wears out you
can turn the screw a notch to a new section. If you have a CC
110 or 120 and want a bargain upgrade, just buy the Chef'sChoice 470
SteelPro manual sharpener - the manual version
of the CC 130 second stage.
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