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eG Forums _ The eGullet Culinary Institute (eGCI) _ Knife Maintenance and
Sharpening
Posted by: eGCI Team on Aug 13 2003, 07:05 AM
Knife Maintenance and Sharpening
By Chad Ward (Chad)
Warning: Remember that handling, using and sharpening knives is inherently dangerous. Neither
eGullet nor the author can be responsible for your safety. That s your job. Knife safety, especially
during sharpening, is a matter of common sense. Keep your fingers, toes and everything else out of
the path of the blade  even if it were to slip. If you go slowly, pay attention and stay focused, you ll
be fine.
Table of Contents
Introduction
Section One: The Sad Truth about Kitchen Knives
Section Two: Steel
Section Three: Edge Basics
Section Four: Sharpening Basics
Section Five: Sharpening Step by Step
Section Six: Maintenance
Section Seven: Overview of Sharpening Systems
Section Eight: Conclusions and Resources
Introduction
 Knife sharpening is hard.
 Sharpening is too difficult and time consuming to do at home.
 Send your knives to a professional sharpener once a year and you will be fine.
 You have to spend hours hunched over a heavy hone slathered with oil.
This well-intentioned advice is parroted in cooking schools, Food Network television programs,
professional manuals and cookbooks. And it is just plain wrong.
Okay, maybe not so much wrong as misleading.
Knife sharpening is not difficult. It is not shrouded in mystery. With a little knowledge, a little
geometry, a couple of tricks and some inexpensive tools, knife sharpening can be fairly easy and
extremely rewarding. At the very least it s a great skill for the toolbox. You ll come away from this
clinic with a better understanding of edges, steel and how to maintain your knives yourself. Or, if
you decide to send them out, you ll know how to make sure you re getting what you want  and
what you pay for.
Section One: The Sad Truth About Kitchen Knives
To a chef, there is nothing more important than his knife. It is not only an extension of his hands, it
is an extension of his very personality. The knife is a chef s paintbrush.
So why are most kitchen knives so bad?
The knives found in most commercial and home kitchens are designed for the lowest common
denominator. The manufacturers of these knives make a series of compromises calculated to keep
the largest number of people happily using their knives for the longest period of time. Like
supermarket tomatoes bred for sturdiness and uniformity rather than flavor, these compromises
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seriously degrade the performance of your knives.
The first compromise begins with the steel. Steel is the heart of the knife. Most manufacturers
(Henckels, Wusthof, Forschner, et al.) have proprietary steel blends and are very close-mouthed
about the actual formulation of their steels. According to industry insiders, these steel blends are
closely related to or equivalent to a steel known as 440a. By and large 440a steel is formulated for
stain and wear resistance rather than holding a high performance edge.
In the kitchen, that s not a bad tradeoff.
But this compromise in edge performance is compounded by a heat treatment that leaves the steel
much softer than it could be. In general, the harder the steel, the keener the edge it will take.
However, a hard steel makes it more difficult to get that edge in the first place. So manufacturers
leave the steel a little soft, theoretically making sharpening at home easier. If you ve ever spent an
hour or two trying to get a super fine edge on a cheap kitchen knife, you ll know that there is a big
gap between theory and practice.
Upper-end kitchen knives like Henckels, Sabatier, Wusthof, et al., are a little better, but are still
softer than they need to be at 52 to 56 on the Rockwell C scale (the
http://www.wikipedia.org/wiki/Rockwell+scale is a scale used to measure the relative hardness of
different solids). By contrast, Japanese knives tend to be around 61-62 on the Rockwell scale.
Custom knife maker Phil Wilson hardens his S90V (a stainless supersteel) chef s and filet knives to
62-63 Rockwell.
The next compromise is in the factory edge angles. Most kitchen knives come with an edge that is at
least 25 degrees per side, frequently even greater. If you add the two sides together you get a 50
degree included angle. And that s the best case scenario. Take a look at a protractor if you happen
to have one lying around. Fifty degrees is extremely thick. An angle that obtuse is more appropriate
for an axe than a chef s knife. Again, the theory is that the thick angles will allow the edge to resist
damage from impaction, rolling and wear better than a thin edge. But, as the song says, it ain t
necessarily so.
Finally, there is just plain cruelty and misuse. While I m certain none of you would ever use the
sharpener on the back of an electric can opener, or use a glass cutting board, or store your knives
loose in a drawer or put them in the dishwasher, it does happen. And when you add soft steel and
thick angles to the general abuse that knives see in the kitchen, you end up with tools that are more
adapted for bludgeoning oxen than fine dicing a soft tomato.
Take heart. The news isn t all bad. We can fix these problems. Geometry is far more important than
steel. With some basic knowledge and the willingness to invest a little time, you can realistically
expect a dramatic increase in knife performance.
First, do no harm: General knife care
- Use wooden or composite plastic cutting boards only. Glass, ceramic, marble and steel will cause
the edge to roll or chip. Bad. Don t do it.
- Don t drop your knives in the sink. Not only is it a hazard to the person washing dishes, but you
can also blunt the tip or edge.
- Don t put your knives in the dishwasher. The heat may damage wooden handles and the edges
may bang against other cutlery or plates.
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- Keep your knives clean and dry. Sanitize if necessary.
- Do not store your knives loose in a drawer. Use a block, magnetic strip, slotted hanger or edge
guards. The magnetic strip is not recommended if you have children or inquisitive pets.
- Finally, your knife is not a can opener, a screwdriver, a pry bar, box cutter or hammer. There s a
special place in Hell reserved for people who abuse their knives this way.
If your knives won t fit in a block, simple plastic blade guards are a good solution
Second: Modify for performance
This is the easy part. Establishing and maintaining high performance edges is what this tutorial is all
about. It can be as simple as steeling with the proper technique or as complex as creating specific
edge bevel and edge aggression strategies for each knife in your collection. It s all up to you.
While you can t change the steel your knife is made from, you can certainly keep your knives at
peak performance  and without too much difficulty. We ll discuss high performance edges and
sharpening strategies a little later in the tutorial.
Third: Modify for comfort
This is something very few chefs (and even relatively few knife makers) take into consideration. Ask
any chef to show you his knife-hand calluses. He ll have a thick one at the base of his first finger
from the  pinch grip used in most kitchens. He or she may also have another on the side of the
second finger where the finger rubs against the bolster or dropped portion of the blade that extends
below the handle.
He will also have aching hands and possible repetitive stress injuries.
In the interest of economy, most knife manufacturers leave the spines of their knives squared off.
The edges of the spine can sometimes be sharper than the knife itself. That edge cutting into your
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finger can lead to blisters, calluses, reduced circulation, numbness and injury.
If you ever handle a chef s knife made by Canadian knife maker George Tichbourne you ll know that
it doesn t have to be that way. Tichbourne worked with several professional chefs when designing
his kitchen knife series. One of the key features is a smoothly rounded spine. It doesn t abrade your
finger, cut off the circulation, make your hands numb or create any of the other discomforts
associated with standard kitchen knives.
You can do the same in less than half an hour. Lock your knife, edge down, into a padded vise. The
padding doesn t have to be anything elaborate. Two pieces of flat rubber or leather will keep the
jaws from scratching the blade. You ll need a sheet of fine (600 grit) wet/dry sandpaper available at
any auto supply store or an abrasive cloth, sometimes called a crocus cloth. Using a gentle
shoeshine motion, lightly round the edges of the spine. You don t have to buff hard or remove a lot
of metal. All you need to do is break the sharp edge at the base of the spine. How far you take it is
up to you. This simple modification will make a world of difference in the comfort of your knives.
Section Two: Steel
An Overview of Steel
By definition, steel is a combination of iron and less than 2 percent carbon. For centuries, carbon
was the only alloying element. The problem in the early days of steel making was getting rid of
unwanted elements, not adding new ones. However, there are a variety of alloying elements that
are added to modern steels to impart various characteristics.
Iron alone is relatively soft. It does not hold an edge well, wears quickly and has little resistance to
bending. Add a little bit of carbon and the story changes dramatically. The carbon combines with the
iron to form hard carbide platelets cemented together in a matrix of iron. The combination is
resistant to wear and bending and will take a keen edge.
Smaller carbides and a tighter grain structure allow for a stronger, sharper edge. Other carbide
formers, like vanadium, can refine the grain of the steel further. Knives with a high vanadium
content can take a very keen edge, but are harder to sharpen.
Carbon - Present in all steels, it is the most vital hardening element. Greater than 0.5 percent
carbon content qualifies a steel as a  high carbon steel.
Chromium - Added for wear resistance and corrosion resistance. A steel with at least 13 percent
chromium is considered  stainless. Chromium is a carbide former, so it also increases wear
resistance.
Manganese - A carbide former. Manganese aids grain structure, increases hardenability, and wear
resistance. Manganese is present in most cutlery steels.
Molybdenum - Another carbide former. Increases hardness, prevents brittleness, makes the steel
easier to machine.
Nickel - Adds toughness and possibly aids in corrosion resistance.
Phosphorus - Essentially a contaminant.
Silicon - Increases hardness and strength.
Sulfur - Increases machinability but decreases toughness.
Tungsten - Increases heat, wear and shock resistance. Tungsten is the strongest carbide former
behind vanadium.
Vanadium - Another carbide former. Contributes to wear resistance and hardenability. Vanadium
refines the grain of the steel, which contributes to toughness and allows the blade to take a very
sharp edge.
Most kitchen knives fall into the category of  high carbon stainless. These knives generally contain
between 0.5 and 0.8 percent carbon, 13 to 18 percent chromium and a little manganese,
molybdenum, silicon, phosphorus and sulphur. This makes for a steel that is easy to produce, is very
stain resistant and reasonably wear resistant. Knives from Global and Mac s Superior line have some
vanadium added for improved wear resistance and a finer grain, which allows the knife to be
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sharpened to an incredible edge.
Carbon Steel versus Stainless Steel
The great debate rages on. Carbon steel advocates claim that their knives take a keener edge, hold
it longer and are easier to resharpen than stainless steel knives. Stainless steel users claim that
carbon steel knives are unsanitary, leave an off taste in foods and that stainless knives hold an edge
longer than their carbon counterparts.
Who s right? Depends on your definitions and your environment. It s not as simple as carbon versus
stainless.
Carbon steels range from simple iron/carbon combinations to high-alloy tool steels that will cut
through concrete without losing their edge. Stainless steels vary from very soft, extremely stain
resistant dive knives to super stainless alloys, like Crucible Particle Metals S30V, a steel
purpose-designed for the custom cutlery industry.
In the far less demanding realm of the kitchen, however, the carbon steel devotees are right. At
least until they actually have to use their knives. Then it s a different story.
Carbon steel kitchen knives generally are a little harder and stronger than stainless steel kitchen
knives. They are easy to sharpen and take a screaming edge. And while the patina that develops on
a carbon knife can be unsightly (unless you like that sort of thing), it isn t unsanitary.
But in the wet, acidic environment of the kitchen, stainless rules. For all their faults, compromises
and shortcomings, stainless steel kitchen knives work better and will hold their edges longer than
carbon steel knives.
Doesn t make sense, does it?
The culprit is corrosion  the effect of acid and micro-rusting. Even on what appears to be a
mirror-bright, razor sharp edge, microscopic particles of rust and corrosion will form, attacking the
edge and reducing its performance. Unless carbon steel knives are rinsed and dried frequently, their
edges will degrade rapidly in kitchen use. The stainless edge will easily outlast them.
According to chef and knife maker http://www.haslinger-knives.com/,  Acids of fruit and vegetables
are fairly aggressive and will dull a carbon blade more quickly than stainless. The acid actually eats
the edge.
Section Three: Edge Basics
Most kitchen knives are flat ground, meaning that the blade tapers directly from the spine to the
edge. Hollow ground, convex ground and saber ground blades are rarely found in the kitchen. I
mention them only to confuse you.
Edges come in a variety of flavors. The most common are the V-edge, double beveled edge, chisel
ground edge and the convex edge.
V-edges and double beveled edges are variations on a theme. The edge found on your kitchen
knives is most likely a V-edge, meaning, oddly enough, that the edge bevels form a V, two surfaces
intersecting at a line of (ideally) zero width.
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A double bevel takes this idea a little further by adding a second, more acute, angle behind the edge
bevel. This secondary bevel is sometimes called a back bevel or relief angle. It s purpose is to thin
the metal behind the edge. The thinner the edge, the greater the cutting ability. However, an edge
that is too thin is susceptible to damage. So you add a smaller, more obtuse primary bevel to the
very edge to give it the strength to avoid damage from impaction, chipping or rolling.
Chisel ground edges are primarily found on Japanese knives, especially sushi knives. The edge is
ground only on one side. The other is side is flat. Hence they come in right and left handed versions.
Chisel ground edges can be extremely thin and sharp. If the edge bevel is ground at 25 degrees and
the other side is 0 degrees, you have an included angle of 25 degrees  considerably more acute
than the average Western knife.
Sometimes known as hamaguri-ba, the convex edge arcs in a rounded curve down to the edge. Thus
the final edge is the intersection of two arcs, creating a very sharp edge with more metal behind it
than the standard V-edge. Convex edges are generally formed on a slack belt grinder, so they are
difficult for the home sharpener to achieve. This can be remedied with the mousepad trick found
later in the tutorial. See the http://home.nycap.rr.com/sosak/convex.htm for sharpening methods
and a comparison of the convex edge with other edge types.
A double bevel. The wide area is a 10 degree back bevel; the narrow section is the 15 degree primary edge face.
The back bevel also solves one of the great problems with V-edges, the fact that the metal behind
the edge gets progressively thicker as the knife is sharpened over time. The knife doesn t cut as well
and becomes harder and harder to sharpen. The answer is to grind the shoulders off the edge at an
acute angle, i.e. add a back bevel, then reestablish the primary bevel.
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If you sharpen your knife without grinding a relief angle, your edge will thicken over time.
Micro-serrations: True or False?
Knife geeks frequently talk about  micro-serrations, microscopic teeth on the edge of the knife. Is
this really true? In a word, yes. Sharpening by its very nature creates a scratch pattern on the edge
of the knife. The coarser the stone, the coarser and deeper the scratch pattern will be and the larger
the micro-serrations. Conversely, the finer the stone, the finer and more polished the edge will be
with less prominent micro-serrations. The real question is, which one is better?
This is one of the great debates in the knife world  the razor sharp polished edge versus a toothier
edge.
John Juranitch in his book  The Razor Edge Book of Sharpening is emphatic that a polished edge is
the answer, that micro-serrations are indicative of a dull knife. His experience comes from
sharpening knives for the meat processing industry. Meat cutters go through knives faster than
tissues in flu season, so Juranitch s conclusions are hard to dispute.
However, Joe Talmadge, author of the Bladeforums  Sharpening FAQ; Cliff Stamp, physicist and
knife nut; Leonard Lee, president of Lee Valley Tools and author of  The Complete Guide to
Sharpening; and many others have come to the opposite conclusion: that micro-serrations, in the
right context, can be a very good thing.
What is the right context? Later on we ll examine the difference between push cutting and slicing,
their applications in the kitchen and the value of various levels of polish on your knife edges. Which
leads us directly to:
The Meaning of Sharpness
What do we mean when we say that we want our knives to be sharp? Seems like a silly question.
We all know what sharp is. Or do we?
Sharpness is not just a function of creating a super-thin edge that will readily sever free-hanging
nose hairs; it s also a function of shape and intended purpose. You could grind your chef s knife to
razor thinness, but the edge would crumble the first time you hit a bone or tried to hammer your
way through a winter squash. Your knife would be sharp but useless. Similarly, a razor sharp but
wedge-thick edge is great on a splitting axe but not much good for carpaccio.
We have to take into consideration the shape of the blade, the angle of the edge bevel and
especially the material being cut when we consider how we judge the sharpness of our kitchen
knives.
So the real question is not  how sharp should my knife be, but rather  how do I get maximum
performance from my knife under a given set of conditions. A sharp knife can be defined as one
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that has a keen edge that can hold up in repeated usage while producing the results we re looking
for in the kitchen.
The Myth of Thick Edges
The theory is that thick edges (larger angles) last longer than thin edges, and the majority of the
knife buying public wants the edge to last as long as possible. But it doesn t work out that way in
practice. Thinner edges actually outlast thicker edges almost all the time.
The thinner edge starts out performing better than the thicker edge. So even if it does degrade it
has a lot of ground to lose before it falls to the performance level of the thick edge.
Thinner edges cut more easily, putting less stress on the edge. If a thin edge takes three slices to
get through a big slab of raw meat, a thicker edge might take six or seven. Or three with a lot more
force. The thicker edge is doing twice as much work, degrading twice as quickly.
Thinner edges are easier to control. Lateral stresses are a significant source of edge degradation.
The more smoothly, accurately and easily you are able to cut, the less lateral stress you put on the
edge.
Thin is good.
A very thin, high performance 10/15 double bevel. The knife is an 8 custom chef s knife in ATS-34 steel from Steve
Mullin.
The High Performance Edge
We want our kitchen knives to cut as easily as possible while maintaining integrity and staying
sharp.
For maximum performance, you want the edge as thin as possible. To borrow an image from Joe
Talmadge, imagine a woman stepping on your foot. If she s wearing tennis shoes, it will hurt a lot
less than if she s wearing stiletto heels. The same amount of force applied to a much smaller area
penetrates better. A knife edge a thousandth of an inch thick with one pound of pressure behind it
concentrates 1,000 pounds of pressure per square inch at the edge. While an actual kitchen knife s
edge will be a little thicker than a thousandth of an inch, the thinner your knife s edge, the more
efficiently it will cut.
To thin a knife s edge, you lower the edge angle. The problem is that a thin edge is much more
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susceptible to damage. As the edge becomes thinner, there is less metal to support it. It can roll,
indent and chip, causing the edge to degrade quickly.
So the goal is to thin the edge as much as possible, but not so much that it is regularly damaged
during hard use. One way to do this is to keep thinning your edge until it reaches an unacceptable
level of fragility then back off a couple of degrees. This is easier than it sounds, but not really
necessary. We ll discuss suitable edge angles in just a moment.
One factor that strongly plays into how thin you can take a knife s edge is the quality of the steel.
That s one of the primary advantages to the new breed of incredibly hard stainless super steels. You
can sharpen them to very acute angles without risk of significant damage. As an aside, I ve taken a
chef s knife made from ATS-34 down to less than 8 degrees per side before it required an
unacceptable level of maintenance.
As we ve discovered, the average kitchen knife is made from pretty mediocre steel. But it can still be
much thinner than the factory edge. As a matter of fact you can sharpen your Henckels and
Wusthofs to angles that would give the good folks in Solingen the heebie-jeebies without worrying
too much.
Section Four: Sharpening Basics
Before we get into sharpening systems and the actual mechanics of sharpening, it helps to
understand some of the basic principles. These are the burr, the sharpening angles, the abrasive,
consistency and sharpening strategy. They apply no matter what sharpening method you choose.
The Burr
First and most foremost is the burr. The burr is your friend. A burr, or wire edge, is a rough, almost
microscopic, raised lip of metal that forms when one edge meets the other. It is the only way to be
absolutely certain that you have fully ground an edge. Essentially you grind one side until it meets
the other and pushes up a small curl of metal. If you stop sharpening before the burr is formed, your
knife will not be as sharp as it could be.
Sometimes you can t see a burr, but you can always feel it. You check for a burr on the side
opposite the edge you have been grinding. Hold the knife blade horizontally and place your fingers
or thumb at a 45-degree angle to the edge and pull gently down and away. DO NOT PULL TOWARD
THE TIP OR HILT; YOU MAY LOP OFF A FINGER. PULL AWAY FROM THE EDGE. Remember, check the
side opposite the one you've been sharpening. You're checking for a very light lip caused by the
edge rolling over to the other side. Check at various points along the edge. The burr tends to form
quickly at the base of the blade but takes a little longer at the tip. You must feel a burr running all
the way from heel to tip to know that you have fully ground that side of the knife.
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Hand position for checking a burr.
The Angles
As we ve discussed, the 50-degree-plus included angle that comes standard on most kitchen knives
is way too obtuse. Leonard Lee suggests anywhere from 5 to 20 degrees per side (10 to 40 degrees
total) for general kitchen work. Five degrees per side is incredibly thin and would require a very
hard, high quality steel to keep that edge in regular use.
For the vast majority of kitchen knives, 15 to 20 degrees per side will provide a significant increase
in performance without requiring undue maintenance. Meat cleavers should be a little thicker, say 20
to 25 degrees per side, while dedicated slicers can be taken down to 10 to 15 degrees per side.
The best compromise in the kitchen has proven to be a 15/20 double bevel. That is a 15 degree
back bevel with a 20 degree primary edge face.
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A 15/20 double bevel illustrated. This is an excellent performer in the kitchen.
Abrasives
You sharpen your knives by scraping away metal. That s really all there is too it. But there is a huge
array of abrasives available.
Traditionalists will demand an Arkansas stone. These stones were originally mined from a novaculite
deposit in Arkansas. They were graded, from softest to hardest, as Washita, Soft Arkansas, Hard
Arkansas and Black Hard Arkansas. However, the best parts of the deposit were mined long ago,
leading to spotty quality in the natural stones. They have since been replaced by ground novaculite
reconstituted into benchstones. These can be found under the Arkansas Perfect name.
Synthetic aluminum oxide stones are very, very hard and don t wear like natural stones. They clean
up easily with a scouring pad and are more consistent in their grading systems. Spyderco and
Lansky both manufacture synthetic stones in a variety of grits (see discussion of grits below).
Japanese waterstones are considered by many to be the ultimate sharpening tools. Although natural
waterstones are extremely expensive and hard to find, reconstituted stones are readily available.
These reconstituted Japanese stones are held together by a resin bond, cut very quickly (and wear
more quickly as well) and are available in extremely fine grits that will put a high polish on an edge.
Synthetic waterstones, as used by EdgePro systems, are formulated from aluminum oxide
specifically for knife sharpening. Like Japanese waterstones, they need to be wet in order to cut
effectively.
Diamond  stones have man-made diamond particles imbedded in or coated on a base metal. They
cut very aggressively and should be used with caution. They were formerly available only in very
coarse grits, but that is changing rapidly. According to Leonard Lee, monocrystalline diamonds are
preferable to polycrystalline diamonds in a diamond stone. They are nearly twice as expensive, but
last much longer. EZE-Lap, Lansky and DMT make excellent diamond stones.
There are two other issues related to abrasives that must be considered: grits and lubrication.
You Want Grits with That?
All of these abrasives come in a variety of grits from very coarse to ultra-fine. Grit refers to the size
of the individual particles of abrasive in the sharpening stone. A stone with a finer grit has smaller
particles, and produces an more polished edge with less prominent micro-serrations. A stone with a
coarser grit has larger particles, produces an edge with more prominent micro-serrations, and tends
to abrade metal away more quickly. There are several different grit rating systems, and
unfortunately it is very difficult to correlate these different systems. For example, Japanese
waterstones are graded differently than diamond stones and both have different numbering systems
than the codes found on powered grindstones. Steve Bottorff, author of  Sharpening Made Easy has
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taken a stab at it http://www.ameritech.net/users/knives/grits.htm if you re interested.
What we do know is that you ll need a coarse to medium stone for shaping the edge and removing
the shoulders of over-thick edges. You ll also need a fine stone for sharpening the final edge. The
combination stones found in most hardware stores just won t do the trick. The coarse side isn t
coarse enough and the fine side isn t fine enough. Any of the sharpening systems mentioned later
will come with appropriate stones.
In very general and imprecise terms, stones rated lower than 300 grit are coarse, 300-400 are
medium, 600+ are fine and 1200 and up are extra fine.
Japanese waterstones have their own grit rating system. They cut so quickly that anything below
800x can be considered coarse, although they ll leave a much more polished edge than a
corresponding Western stone. 1000x and 1200x can be considered medium and medium-fine and
make an excellent general purpose stones. Waterstones can go up to 8000x, but that s really overkill
for kitchen purposes.
The stones that come with Spyderco s Sharpmaker are listed as fine (the white stones) and medium
(the grey stones). The grey has been compared to an approximately 800x waterstone, the white to
a 1200x waterstone in effect.
The synthetic waterstones from EdgePro systems also have an idiosyncratic rating system. The
coarse stone is listed as 100, the medium as 180, the fine 220, extra fine 320, ultra fine is 600.
However a conversation with Ben Dale, owner of EdgePro, revealed that the extra fine stone is
equivalent to a 1200x Japanese waterstone and the ultra fine equivalent to a 2000x Japanese stone.
The basic system comes with a medium and fine stone, which should be sufficient for most needs,
though the coarse stone comes in handy for quickly reshaping bevels.
Oil or Water?
Everyone knows you need to lubricate your sharpening stone with water or oil, right? So the
question is which one is better. Neither. The purpose of a sharpening stone is to grind the edge and
remove metal. Oil reduces friction and makes the process much slower.
Supposedly oil helps float away metal particles that would otherwise clog the pores of the stone. You
can do the same thing by wiping the stone with a damp cloth when you re done. Steve Bottorff
reports that you can clean your Arkansas stones with paint thinner. Synthetic stones clean up with a
scouring pad and abrasive cleanser.
According to Joe Talmadge, if you have already used oil on your Arkansas stone, you ll probably
need to keep using oil. But if you have a new Arkansas stone, a diamond stone or a synthetic stone,
go ahead and use it without oil or water. It will work much better.
John Juranitch reports that in his company s work with meat processing plants they discovered that
the metal filings suspended in the oil on a stone actually chip and abrade the edge. Although these
chips were only visible through a microscope, the meatpackers readily noticed the difference
between the knives sharpened on a dry stone and those sharpened on oiled stones.
Waterstones are another matter entirely. Both Japanese and synthetic waterstones require water in
order to cut effectively. Japanese waterstones can be damaged if used dry and must be soaked
thoroughly before use. Waterstones wear very quickly, revealing new layers of cutting abrasive as
the swarf builds up and is washed away. That s why they are so effective. There is always a new
layer of sharp abrasive cutting away at the metal of your edge. By the way,  swarf is one of those
cool terms you get to toss around when you discuss sharpening. Swarf is the slurry of metal filings
and stone grit that builds up as you sharpen. Throw that into your next cocktail party conversation
and just watch the expressions of awe appear as people realize that you are a sharpening God.
Consistency
You must be able to maintain a consistent angle while you are sharpening. This can be tough to do,
which is why there are so many gimmicks and sharpening systems on the market. They don t
provide any magic. All they do is help you keep your edge at the same angle throughout the
sharpening session.
Maintaining consistency is a primary reason freehand sharpening with benchstones or waterstones is
a little tricky. It takes a lot of experience and practice to keep the edge at a constant angle stroke
after stroke using only your hands and eyes.
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Sharpening Strategy: Coarse versus Polished Edges
Related to the grit discussion above, the finer the stone you use to sharpen your knife, the more
polished your edge will be. And while it can be a lot of fun to create a scary sharp edge that will cut
the tops off of arm hair without touching the skin, it s really not necessary or ideal for kitchen use.
As a matter of fact, leaving the edge of your knife just a little coarse can be a very good thing. This
is where we must compare push cutting to slicing.
Push cutting involves parting fibers and requires a polished edge. Shaving, for example, is push
cutting. So is peeling an apple or julienning a carrot. You are pressing your thin, finely polished edge
through the fibers of the food, pushing them to either side.
Slicing, on the other hand, involves severing fibers and requires a toothier edge. Crusty bread, a soft
tomato, roast chicken  anything with an outer layer that is tougher than the squishier inside
demands an edge that can bite into the skin without crushing the interior. A highly polished edge will
simply skate over the surface of a ripe plum until you put enough pressure on it to push through the
skin. But the fruit underneath will give way before that happens. Not pretty.
Now you must decide. Do you do more push cutting or more slicing? Do you have knives that you
use more often for dicing, peeling and julienning? Do you have a knife that is dedicated to slicing?
A good basic strategy is to start with a standard 20 degree bevel (a 15/20 double bevel if you re
feeling adventurous) with a moderately polished edge on all your knives. This alone will be a vast
improvement over what you might be used to.
Then branch out. If you have a knife that is only used for vegetables, a santoku for example, you
can take it to a very fine, highly polished edge. A dedicated slicer can be finished on a medium-fine
grit stone, leaving the edge slightly coarse. Your chef s knife can be somewhere in between.
There is one caveat. The thinner the edge, the finer it will need to be to avoid excessive damage. A
coarse edge wears more quickly and requires more maintenance. This is usually not an issue unless
you like your edges very thin. Then a polished edge will last longer. Of course if you have a very thin
edge it will probably push cut through materials that a thicker edge might have to slice through, so
you re not losing any slicing performance.
If you re really nuts you can create a dual edge on your knives. This would be a slightly coarse
section at the back of the blade near the choil or bolster. The rest of the blade would be finished on
a fine or extra fine stone. That gives you a toothy section for cutting through tough materials as you
begin your stroke and a finer edge for push cutting through the rest. Yes, this is only for the
seriously deranged.
Section Five: Sharpening Step by Step
Hey, 5,000 words into this and we re actually getting to the  how-to part.
Okay, here s where we put all of this together.
Haul out your sharpening rig and let s grind some metal. Don t have one yet? Check out the
Sharpening Systems section below to see what suits you best.
Got one now? Good.
Remember the basics: burr, angle, abrasive, consistency and strategy. Let s assume, for the sake of
discussion, that you ve decided to put a 15/20 double bevel on your chef s knife. Because it s a
general purpose knife, it doesn t need to have a mirror polished edge. As a matter of fact, a good
medium-fine edge is what you re aiming for. This is your angle and strategy.
Because this is the first time you ve really tried to change the horrid factory edge, you ll need to
begin with a fast cutting, coarse abrasive. Benchstone, waterstone, Sharpmaker grey stone 
doesn t matter. Start with the coarsest thing you ve got.
Determine how you re going to establish consistency. With a Sharpmaker you simply stroke straight
up and down. The EdgePro or Lansky rod-type systems have angle guides built in. Freehand
sharpening requires a little more skill and patience, but if you use a guide system like the Razor
Edge or simply place your thumb on the spine in the same spot every time, you can create a
consistent angle.
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Advanced Section:
QUOTE
Warning: Math! If you want to be really anal about it, Leonard Lee offers this formula for creating
freehand angles of less than 20 degrees.  Use the basic rule that a 1 degree angle subtends an arc
of 1 unit at a radius of 60 units. The 1-in-60 rule is close enough for many purposes, particularly
sharpening at low angles. You ll find that a 10-unit rise in 60 units is about 9-1/2 degrees and a
20-unit rise is about 19 degrees.
This works out to raising the spine 1/8 inch (measured 1.5 inches back from the edge) for every
five degrees of angle. The average chef s knife is about 1.5 inches wide at the heel, so for a 15
degree angle you d raise the spine 3/8 inch  about the height of six quarters stacked up.
If your knife is wider or narrower than 1.5 inches, measure the height from 1.5 inches back from
the edge, otherwise the math doesn t work. It s the height/width ratio that gives you the angle.
Forget the math. In a pinch a large binder clip clamped to the spine will get you pretty close.
So, let s get started:
1) Establish your 15 degree angle. If you re using a Sharpmaker, put the stones in the 15 degree slots.
With a Lansky, Gatco or EdgePro system, slide the rod into the 15 degree setting. With edge guides,
clamp the guide at the 3/8 height. Freehanding, raise the spine to 3/8 inch measured 1.5 inches back
from the edge.
Now you re ready to create a burr. Be patient, this might take a while. To grind off the shoulders of the
previous edge we re going to be removing a lot of metal. That s why we need the coarse stone. At this
point it doesn t really matter what kind of stroke you use. You can go heel to tip or just grind in circles.
It doesn t make any difference.
To keep the aesthetics of the knife, you ll want the bevels relatively even on each side. If you just grind
one side until you get a burr, the other side will require much less grinding. Thus the bevels will be
mismatched. To keep them matched, grind one side for about five minutes or so then switch to the
other side, maintaining your approximately 15 degree angle. Feel the knife every so often to see if you
can feel a burr. Keep grinding and switching sides until you detect a burr beginning to form. Remember,
the burr forms on the side opposite from the side you are grinding. If you don t remember how to check
for a burr, see the picture earlier in the tutorial.
As soon as you detect a burr, keep grinding on the current side until the burr runs the entire length of
the opposite edge.
If you use the Magic Marker Trick described below, you can save a little time on this step.
2) Repeat on the opposite side until you feel a burr along the full edge of the first side.
3) Optional: If you want to dress up the scratch pattern, switch to your fine stone and give the edge
several passes on each side (at the same angle) to polish them out a little.
4) Establish your 20 degree angle. If you re using a Sharpmaker, switch to the 20 degree slots. With a
Lansky, Gatco or EdgePro system, simply change the rod to the 20 degree setting. With edge guides
unclamp the guide and slide it forward about an 1/8 to 1/4 inch. Freehanding, raise the spine another
1/8 inch. If you switched to your fine stone, switch back to your coarse stone or the next one up,
usually a medium stone.
5) Create a burr again at the new sharpening angle, going back to side one. This time you re grinding
the edges to meet at a 20 degree angle. This will happen very quickly because you ve already removed
most of the metal you need to. The 20 primary edge face will be very narrow compared to the 15
degree back bevel, somewhere around 1/32 to 1/64 of an inch.
6) Switch sides and repeat until you have a burr running the full length of the first side.
7) You re almost home. Now that you ve got your burr you need to grind it off completely so that the
true edge remains. Now technique matters. No more grinding in circles. Stroke gently from heel to tip,
alternating sides with each stroke. Keep the sharpening stone perpendicular to the blade as usual,
beginning the stroke at the heel and ending at the tip. Or if you are sharpening on a benchstone, stroke
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tip to heel, if you re more comfortable that way. Lighten up on the pressure as you go. There is no hard
and fast rule, but five to 10 strokes per side should do it. If your checking reveals that the burr is simply
flopping from side to side, lighten up the pressure even more.
8) Change from the coarse or medium stone to the fine stone and continue. Keep stroking side to side
until all the scratches from the coarse stone are gone. Continue lightening up on the pressure as you
proceed. You are trying to grind the burr off. If you press too hard you ll simply form another one.
9) Finish with a few very light strokes on the fine stone. Now, to make sure that the burr is completely
gone, place the knife on the stone as though you were going to take one last stroke, but this time
increase the angle just a hair. On a Sharpmaker, tilt the knife very, very slightly in toward the center to
increase the angle. Now guide the knife down the stone using no more pressure than the weight of the
knife itself. Switch sides and repeat for one stroke. You can do this for one more stroke per side if you
can still feel any vestige of a burr.
If you have a smooth steel or very fine grit ceramic rod you can substitute a couple of strokes per side
at a slightly greater than 20 degree angle for this last step (see discussion on steels and steeling
below).
Your edge should be frighteningly sharp at this point. If it s not, you might not have fully ground off the
burr. The edge could simply be turned to one side. Try the fine stone and light pressure again. It could
also be that rather than grinding off the burr it was simply turned straight down. This will give you an
edge that will send shivers down your spine but it will break off in the first use. A light touch at the end
of the sharpening process is the key.
If you want your knife too look as good as it performs, progress through the coarse, medium and fine
stones at each angle setting while you re raising your burr. This will remove any deep scratches and
give the edge a more refined look.
This edge is not only very sharp, but is relatively strong. With regular steeling it will last for many
months, even under hard use. When steeling ceases to have the desired effect it s time to sharpen
again. However, now that you ve ground the back bevel you really only need to sharpen the 20 degree
primary edge. If your knife is very dull go back to step four on the coarse stones. If it is only a little dull
you can begin with the fine stones. The burr will be very easy to raise in subsequent sharpening
sessions.
Tips and Tricks
There are a couple of tricks that can make the sharpening process even easier. I ve saved them until
the end just to be cruel.
The Magic Marker Trick
One of the easiest ways to ensure that you are matching an existing bevel is to coat the edge with
magic marker. As the magic marker is abraded away by the sharpening stone. you will be able to see
where the metal is being removed and whether you have matched the angle properly. Once you have
coated both bevels with marker, take a swipe or two down your stone. If the marker is wiped off over
the width of the bevel you have matched the angle properly. If your angle is too high, only the marker
near the very edge will be removed. If your angle is too low only the marker near the shoulder, above
the edge, will be removed. Recoating the edge as you sharpen is a good way to ensure that you re
holding the correct angle throughout the process. No matter what type of sharpening system you use,
the magic marker trick will save you a lot of time and frustration, especially in matching an unknown
angle on one of the guide or rod-style systems.
The magic marker trick also comes in handy when you are establishing a back bevel. If you coat the
edge before working at the 15 degree setting you can grind the back bevel until the marker is ground
almost to the edge, leaving 1/32 to 1/64 inch. That s about how wide the primary edge face will be.
Rather than grinding all the way to the edge until you get a burr, you can now switch to the 20 degree
setting, knowing that the last little bit of edge will become the primary edge face. You still have to raise
a burr at 20 degrees, but the marker trick can save you a little time.
The Paper Airplane Trick
Take a piece of paper with square edges. Fold the bottom left corner over until it meets the right edge.
Smooth it down. You ve just turned a 90 degree angle into a 45 degree angle. Fold the creased edge
over to the far right edge like you re making a paper airplane. You ve just folded it in half again, and
you have a 22.5 degree angle. Sound familiar? Twenty-two and a half degrees is pretty dang close to 20
degrees. As close as you can generally hold a specific angle by hand. This folded piece of paper can
serve as a guide for steeling your knife, setting an angle on a benchstone or just checking that you re
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keeping your angle steady as you sharpen. The paper edge guide is especially handy when you are
learning to steel your knives properly. It helps build the right angle into muscle memory so you can do it
without the guide when you have a little more experience. Fold the paper again and you have an 11.25
degree guide for steeling those super thin slicing knives that you ve sharpened to 10 degrees per side.
The Mousepad Trick
Do you have an old mouse pad? Is there an auto supply store nearby? You can make a superb
sharpening system for about $5.
Go to your nearest auto supply store and get some 600 grit sandpaper. Mylar-backed wet/dry
sandpaper works best. This is the stuff used to sand automotive paint between coats. Get the self-stick
kind. If they have higher grits, get a couple of sheets of those, too, 1200 grit is generally the next step
up. Go nuts. It s cheap.
Stick the sandpaper to the mouse pad and trim the edges. This is your new sharpening system. If you
have both 600 and 1200 grit, apply one to each side of the mousepad. Make sure you have a work
surface you don t mind scratching up. If you have a double-sided mousepad sharpener, you don t want
to work on your kitchen counter or dining room table. Your spouse will kill you.
This system requires a stropping motion when sharpening, using an edge-trailing stroke. That means
that unlike other sharpening methods you don t lead with the edge, you lead with the spine. Image an
old barbershop with the barber stropping his razor, stroking away from the edge. That s the idea.
To establish your angle, lay the knife flat on the pad, edge toward you. Lift the spine slightly while
pulling lightly toward you. Continue lifting until the edge bites into the sandpaper. That s your stropping
angle.
Press down lightly and stroke the knife away from you, spine first, moving from heel to tip. When you
reach the end STOP and lift the knife straight up off the sandpaper. Don t roll it off or lift the spine
further or you ll mess up the edge you re creating. Turn the knife over and stroke back the other way
with the edge away from you, pulling the spine toward you at the same angle as the previous stroke.
The really cool thing is that the mouse pad is soft enough that it conforms to the angle of the knife
edge. As long as you re pretty close you ll be fine. This will give you an amazing edge in a fairly short
amount of time. If you want to polish it up, use the higher grit sandpaper on the other side of the
mouse pad.
Because the mousepad is soft, it deforms lightly around the edge of the knife and gives you a slightly
convex bevel. As we ve discussed, a convex edge has many advantages but can be difficult to achieve
without a belt sander. This is one way to create or maintain a convex edge without serious power tools.
This is the same technique as stropping (below) but with a different abrasive.
Stropping
Stropping is a handy way to finish off a burr or put a final mirror polish on your edge. While you can
strop on anything from the back of a legal pad to an old belt, places like Lee Valley Tools and
HandAmerican sell hard backed strops. The strop is usually charged with an abrasive, like green
chromium oxide paste, so it actually does remove very fine particles of metal.
Like the mousepad trick above, stropping is an edge trailing stroke. Lay your knife flat on the strop with
the spine facing away from you. Slowly pull the knife toward you while lifting the spine. When the edge
just begins to bite into the leather you have found your angle. Keep that angle as you stroke the spine
away from you, pulling the edge along behind. When you get to the end of the stroke STOP. Lift the
blade straight up off the strop. Do not lift the edge higher or roll the knife over while it is still on the
strop. You can wreck your edge that way.
Now lay the knife flat again, spine toward you, and gently push the edge toward the end of the strop
while lifting the spine. When the edge begins to bite you ve found your angle for the return stroke. This
second step isn t really necessary if you ve kept your angles consistent during sharpening, but it never
hurts to make sure you are holding the right angle. The return stroke is the same motion as the first
stroke, simply in reverse. The edge is facing away from you and you pull the spine toward you.
Stropping will create an extremely sharp, highly polished edge optimized for push cutting. To some
extent, stropping can make up for less than perfect sharpening technique, especially since it s a little
more forgiving.
Handling Serrated Knives
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Serrated knives and bread knives are a special case. Serrated knives will stay sharp longer than plain
edged knives, mainly because the insides of the serrations generally don t contact hard surfaces. That s
what the teeth are for. The teeth not only have a cutting function, but are also sacrificial lambs, offered
up to steakhouse swordsman and children everywhere who feel that if they re not grinding into the
ceramic of the plate, they re not cutting.
There are four ways to sharpen serrated knives:
1) Pretend the serrations don t exist and sharpen on a stone, sharpening system or electric sharpener
as you would a plain edged knife. This will eventually remove the serrations.
2) Sharpen the flat, non-serrated back of the blade. This will sharpen the knife, but also will eventually
remove the serrations, though not as quickly as the first method.
3) Sharpen the serrations individually with a tapered diamond or ceramic file.
4) Sharpen on a crock stick setup, going very slowly so the ceramic rod glides in and out of the
serrations.
This last method actually works fairly well, especially with the Spyderco Sharpmaker. It s triangular rods
fit into serrations much easier than the standard round crock sticks. If you want to keep your serrated
knives as sharp as they can be, the Sharpmaker system is the way to go, though the Lansky rod-guided
system also has an accessory hone for sharpening serrated edges.
Chisel Ground Edges
Sharpening chisel-ground or single-bevel knives is not tricky. You simply match the bevel angle and
sharpen as usual  but only on the beveled side. When you raise a burr, grind it off by laying the flat
side of the knife perfectly flat against your stone and swipe the burr off. It only takes a couple of
passes. You can do the same thing with a strop. The back side of the knife must be perfectly flat or
you ll round your edge. All you want to do is grind off the burr.
The back side of a sashimi knife is sometimes lightly hollow ground to make this step easier. You can
actually lay the knife flat and sharpen with your usual stroke, edge first across the stone.
How to Tell if Your Knife is Sharp
How do you know when you have achieved the ultimate high performance edge? Depends on what you
want to do with it. Remember that we defined sharp not only as two edge faces intersecting at a line of
minimum width, but also as a function of blade shape, angle and the material to be cut. We want a keen
edge that can hold up in repeated usage while producing the results we re looking for in the kitchen.
You can tell when you ve set your knife s edge bevels correctly by placing the knife at a 30-45 degree
angle on your thumbnail and pulling across the edge. A properly set edge will bite in and not slip off
your nail. Of course, you could hurt yourself doing this, too. Or, at the very least, wreck your nail polish.
Any slick, slightly rounded surface will do. Take, for example, a plastic pen, stand it at a 30-45 degree
angle on a countertop and lay the knife edge straight up and down on the plastic. Pull the edge from
heel to tip. If it bites in, you ve set your edge correctly. If it slides off, you have some more work to do.
The sharper the blade, the smaller you can make the angle before it slips.
Another test is to take a Q-tip and push the fuzzy head over the edge. Any nicks or burrs will pull the
cotton fibers loose from the head. The Q-tip will also reveal any rough spots in the edge. A
well-sharpened edge will feel smooth. This test is more effective for polished edges.
Razor Edge Systems makes an Edge Tester for this very purpose. It is widely used in the meat cutting
industry to check edges to see if they need sharpening (or if the meat cutter is just goofing off).
Another check is the  Samurai Hair Test. Lay the knife nearly flat against the hair on the back of your
head and pull gently down. Very gently. An aggressive, keen edge will readily grab the hair. A dull edge
will simply slide off. Don t shave the back of your head. Just pull gently down to see if the edge catches
and tugs. I don t want any irate calls from your barber or hairstylist.
The classic test of sharpening is shaving the hair of your arms. This has several problems, not the least
of which is that the hair might not grow back or could come in coarser and darker than the surrounding
hair. And if you have a lot of knives to test you ll end up looking like you have mange.
The real problem with shaving, though, is that shaving is push cutting. A highly polished edge will
readily push cut, but, as we ve discovered, you don t always want a highly polished edge. A slightly
coarse edge that tugs the hair but doesn t shave will actually slice better than the polished edge. Thus,
shaving isn t the best test for many knives.
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There are other opinions on shaving as a test. Cliff Stamp said,  Coarse edges can easily shave, Joe
Talmadge was one of the first guys to comment on this. A lot of people think they can't and thus
sharpen them pretty sloppily. The more coarse an edge you form, the sloppier you can get and still have
decent cutting ability. However you can get better cutting ability but keeping the edge crisp and aligned.
This edge will then have a much higher level of push cutting ability, overall durability and edge
retention, as well as a slightly higher level of slicing aggression. I have seen edges formed from a 100
grit AO belt that would still shave. This is more coarse than a x-coarse DMT hone.
Slicing newsprint is a pretty good test. Both highly polished edges and toothier edges (as long as they re
not overly coarse) will readily slice a piece of newspaper held lightly between your fingers.
The best test, though, is actually using the knife for its intended purpose. If you have a slicing knife, try
a soft tomato or plum. A keen, toothy edge can bite into the tomato with little or no pressure, just a
light draw across the skin. If you have polished your santoku to a mirror-like edge, try dicing a few
carrots or potatoes. The reduced effort will be immediately noticeable. And greatly appreciated if you
have 50 pounds of beets to get through before service.
A thin, slightly coarse slicing knife will cut a soft tomato with a light pull and nearly no pressure on the blade.
Posted by: eGCI Team on Aug 13 2003, 07:06 AM
Section Six: Maintenance
Why Edges Wear
The ability of a knife to hold an edge is affected by several factors. Many are properties of the steel,
others are job-specific.
Wear resistance  the ability to resist abrasion  comes primarily from the amount, type and
distribution of carbides in the steel.
Strength is resistance to low-impulse deformation. In other words, bending. Strength is directly
related to the hardness of the steel.
Toughness is resistance to high-impulse deformation  impacts, chipping and cracking.
As a general rule, strength and toughness are inversely related. A hard, unbendable steel can be
brittle. It will not withstand chopping through bone as well as a tough, slightly softer steel. A tough
steel might roll its edge if it encounters significant lateral stress or is forced through very hard
materials  stresses that a strong steel would easily resist. The most extreme examples of both
would be the extremely hard, yet shatter-prone ceramic knives from Kyocera compared to very
tough, soft stainless Chinese cleavers.
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Edge holding is a function of wear resistance, strength, toughness and the tasks the knife is used
for. Toughness is required to resist chipping when you are cutting through materials where you
might encounter bone or other hard bits and pieces. Strength is required to resist rolling and
impaction if, for example, someone in your kitchen (despite repeated warnings) uses a glass cutting
board. Wear resistance becomes important for edge holding when you re cutting through abrasive
materials.
So the way your knife holds an edge depends on the steel and what you use the knife for.
The most common culprits that put wear resistance, strength and toughness to the test are:
Wear. Duh. As a knife blade encounters abrasive materials, the edge wears away. Unless you cut
only soft foods, your edge will always wear somewhat, though the most wear in the kitchen will
come from sharpening your knives. Significant wear could take years.
Indenting and rolling. As pressure is put on the edge of the blade (and remember, the edge s job is
to concentrate tremendous amounts of pressure), the edge can indent, impact or roll over to one
side or the other. The harder the steel, the less likely it will be to indent or roll. This is actually fairly
common in the kitchen, which is why you need to steel frequently (more on this below).
Chipping. The edge can chip or crack under impact, especially when encountering hard materials like
bone. Micro-chipping can be an important factor in edge degradation, although kitchen knives are
fairly tough.
Corrosion. The wet, acidic environment of the kitchen can give knives a real beating. Micro-rusting
and the attack of acidic foods can lead to edge loss at the very apex of the edge in short order.
Technique. As chef Thomas Haslinger points out,  Having sharpened my own knives and other chefs
knives, I can say that an often overlooked factor in cutting edge performance is how each individual
holds and uses his knives. A person that  feels the cut will always have a knife that outperforms an
individual who just cuts and slams the edge into the cutting board
Steeling your Knife
Steeling regularly is the most critical maintenance you can perform on your knife. Whenever you use
your knife, especially soft kitchen knives, the edge can turn out a bit. Turn the knife with the edge
pointing to the ceiling under strong light. You shouldn t be able to see it. The edge itself should be
invisible. If, however, you see glints of light, those are spots where the edge has rolled. The edge is
still reasonably sharp, it s just not pointing straight down anymore. The steel realigns the edge of
the knife, forcing the rolled spots back into line, making it useable again.
We will get into the various types of steels in just a moment, but be aware that the grooved steels
that come with knife sets do in fact remove metal. A grooved steel acts as a file when used with a
heavy hand, knocking microscopic chips out of your edge. At the very least, it is much coarser than
the fine abrasive you used to achieve your edge. Steeling heavily with a grooved steel is taking
several steps backward. A grooved steel should be used with caution and a very light touch.
The standard image we all have of steeling a knife involves a chef with his knife in one hand and
steel in the other, blade flashing and ringing. If you re particularly adept at this type of
swordsmanship, have at it. It impresses the tourists.
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A more effective method is to stand the steel straight up and down with the handle up and the tip
resting on a folded towel to keep it from slipping. Why? Geometry.
Place the knife edge against the steel with the blade perpendicular to the steel  90 degrees, right?
Rotate your wrist so that you reduce the angle by half  45 degrees. Reduce that by half  22.5
degrees, and you are exactly where you need to be to steel your knife (if you have a 20 degree
edge). You generally want to steel at a very slightly steeper angle than the edge bevel itself.
The most effective way to steel your knife. Note that I should be standing squarely in front of the steel. I had to lean a
little to get the knife to show up well in the shot.
You can also use the Paper Airplane Trick to make a guide to prop against your steel so you know
you are hitting the proper angle.
When you re steeling, lock your wrist and stroke the knife from heel to tip by unhinging at the
shoulder  it s your pivot point  and slowly dropping your forearm. The key is to maintain a
consistent angle all the way through the stroke. By locking your wrist and elbow, you will keep your
angle stable from top to bottom. Go slowly and follow all the way through the tip. You don t have to
press very hard to realign the edge. Steeling requires barely more pressure than the weight of the
knife itself.
Alternate from side to side, keeping the same alignment and angle on both sides. It really only takes
four or five strokes per side to get your knife ready for more work.
When should you steel? Every time you use your knife. Oddly enough, steeling before you use the
knife is much more effective than steeling afterward. A steeled edge can be very sharp, but it is not
as durable as a freshly honed edge. If you don t use a steeled edge right away it can actually relax
back into its blunted state. The same is true of a blunted edge. If you really degrade the edge of
your knife in a heavy cutting session, let it sit overnight before sharpening. It will be in much better
shape than it was the day before.
You should also steel before sharpening so any rolled or impacted edges are pushed back into
alignment. That way you don t cut off the rolled edge and lose more metal than you really need to.
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You also can steel after sharpening to add a final bit of polish (especially on a medium to medium
fine edge) and tooth alignment. A steel actually  smears the edge, teasing out a little more
thinness. You ll have a keener edge, but it will be weaker than the freshly sharpened edge.
Types of Steels
Knife steels come in a variety of sizes, shapes and flavors. There are round steels, oval steels,
grooved steels, smooth steels, diamond steels and ceramic  steels. If you purchased a set of
knives, it probably came with a round, grooved steel. Be very careful with this beast. Kitchen knives
are reasonably tough and resist chipping fairly well, but a grooved steel can really put that to the
test. The grooves in the steel create tiny points of contact with the edge. A smaller contact area
makes for greater pressure on the edge. Used lightly, a grooved steel can realign the edge of your
knife, though it does it fairly aggressively. Used with too heavy a hand, however, a grooved steel
will act as a file and take microscopic chips out of your edge. Your edge will feel sharp because it is
now, in effect, serrated, but it won t last very long.
Coarse diamond steels fall into the same category, though they ll generally leave a finer edge than
grooved steels. They should still be used with caution and a very light hand.
L to R: Grooved steel, smooth steel and 700 grit ceramic rod.
Smooth steels are several steps above either grooved or diamond steels. A smooth steel will gently
push the metal of the edge back into alignment. It will take longer than with a grooved or diamond
steel, but you don t run the risk of damaging your edge. A smooth steel is very easy to use and
fairly forgiving of sloppy angles.
A step above even smooth steels are fine grit ceramic and very fine diamond steels. According to
Cliff Stamp,  A smooth steel just pushes the edge back into alignment, leaving the weakened metal
there, which will actually relax back into being deformed in its own time without any use. The
ceramic will remove some of the weakened steel while also aligning the edge. The edge will be more
stable and stay sharp for much longer. There is more metal removed with the ceramic and diamond
rods, but you are looking at between 100 to 1000 sharpenings to remove one millimeter of metal
from the edge of the knife depending on the edge angle and the grit of the ceramic or diamond hone
 this is years of constant use. In general, the lifetime of most knives tends to be dominated by the
occasional accidental damage that forces heavy honing.
Section Seven: Overview of Sharpening Systems
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Like everything else in the kitchen, sharpening is just a matter of understanding a little science and
practicing a lot. And sometimes it means buying more stuff, but that s half the fun, isn t it?
Benchstones and Waterstones
If you d like to try freehand sharpening, get the biggest stones you can. A good rule of thumb is to
use a stone that is at least as long as the longest knife you intend to sharpen. The minimum size to
avoid major frustration is 6 x 2 . As we discussed in the Grit section, you ll need at least one coarse
to medium stone and one fine stone. If you d like to try Japanese waterstones, Lee Valley Tools has
a good selection of inexpensive stones. Some even come in kits to get you started quickly.
Freehand sharpening is a technique best learned face-to-face. If you have learned to freehand, you
have mastered one of the most difficult, yet most rewarding, sharpening methods available. There is
real satisfaction in attaining the skill to sharpen a knife to hair-flinging sharpness using nothing more
than a stone and your own knowledge.
Guide Systems
There are a variety of guide systems available. These systems clamp on to the back of the knife and
keep your angle steady throughout the sharpening stroke. The guide is used with a benchstone or
waterstone and uses the same motion you d use for freehand sharpening. The advantage to the
guide systems is that you not only keep your angle steady, but you also build the proper stroke into
muscle memory. Using a guide for a while will improve your freehand sharpening. Because the guide
takes up space, you lose a couple of useable inches of space on your stone. This is not really a
problem if you have a sharpening stone 8 or longer.
Another disadvantage to guides is that you re never sure exactly what angle you are grinding into
your edge. Most of the time, knowing the exact angle isn t a big deal, but if you are trying to achieve
exact, repeatable bevels, you ll have to use the Magic Marker Trick and perhaps the calculations
provided by Leonard Lee.
The most popular guides come from Razor Edge Systems. These are fairly easy to use but require a
lot of dexterity to clamp properly. Razor Edge also produces an instructional video on the use of its
guides and sharpening stones.
According to Steve Bottorff, the best guide available is the now-discontinued Buck Honemaster. If
you can find one at a garage sale or on eBay, go for it.
Rod and Clamp Systems
These are very popular systems and there are several available. The best are made by Lansky, DMT
and Gatco. The knife is held in a clamp. The stone is attached to a rod. By putting the rod through
one of the pre-set holes in the clamp, you can control the sharpening angle. Double beveling is very
easy with these systems.
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Lansky sharpening set.
Steve Bottorff has tried just about every sharpening system available. Here s his take on the Lansky,
Gatco and DMT systems.
 The Lansky has an aluminum guide that goes from 13 to 25 degrees in 4 steps; each angle is 3 to 5
degrees lower than indicated. The GATCO guide is aluminum and reinforced plastic and goes from 17
to 34 degrees in 6 steps, each step is about 6 degrees greater than indicated. I prefer the GATCO to
the Lansky because of the GATCO's larger stones and selection of angles. The DMT Aligner guide is
all plastic, and goes from 12 to 35 degrees in 7 steps, which are not marked. With DMT hones,
which I do not have, the Aligner would be the pick of the litter for this size of system.
The downside to the Lansky and Gatco systems is the need to reclamp the knife every couple of
inches so you don t change the bevel angle as you progress from heel to tip. It is also fairly easy to
round the tips of your knives on these systems.
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The Lansky in action.
The king of the rod and clamp systems is the EdgePro Apex. Ben Dale, the owner of EdgePro, has
created an excellent, easy to use system that can handle any kind of knife you care to throw at it.
He is also a great person to deal with and is more than willing to spend time on the phone with you
answering any question you might have.
EdgePro Apex sharpening setup.
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The Apex is rugged and uses relatively large 1 x 6 inch aluminum oxide waterstones. The angle
guide is continuously adjustable for any angle, with marks at 10, 15, 18, 21 and 25 degrees. The
blade table can harbor runoff grit and metal shavings, scratching the blade unless you tape it with
painters tape. I don t bother. My knives are tools. I don t mind if they re a little ugly.
The only downside to the EdgePro Apex is its cost. This is a fully professional sharpening system, but
at $125 before stone upgrades it is a little outside the realm of what the average home sharpener is
willing to spend. I have one, and you ll have to pry it out of my cold dead hands to take it away.
EdgePro in action. Note that the blade is not clamped, making it easier to maintain a consistent angle from heel to tip.
EdgePro offers a video that demonstrates the proper use of the system. The quality is little better
than a home movie, but the information really helps.
V-Systems and Crock Sticks
V-type sharpeners have two ceramic sticks set into a plastic base at a preset angle. The knife is held
perpendicular to the ground and stroked down the side of the sharpening stone. Because you are
holding the knife in a natural position, these systems are fairly easy to use.
Rather than review all of the crock stick setups out there, let me save you some time. Spend the
$40 and get the Spyderco Sharpmaker 204. If you get one on eBay, make sure you re getting the
204 rather than the older 203. The 203 doesn t have the 15 degree back bevel slots.
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Spyderco Sharpmaker 204. And my cat, Chester.
These can be found in many sporting goods stores, knife stores and on the Internet at
Knifecenter.com, Knifeoutlet.com and many others. I d buy it from Michael Dye at
http://www.newgraham.com/sharpene.htm. He s a great guy and has excellent prices and customer
service.
The Spyderco is a nifty system because the angles are preset for performance edges. You don t have
to guess, just hold the knife straight up and down and stroke it down the stones. There are two
angles, 30 and 40, corresponding to 15 degrees per side and 20 degrees per side. It s pretty much
foolproof. This is about the easiest system to use. And, unlike just about anything else out there,
you can sharpen serrated knives. It comes with an excellent manual and a video to help get you
started.
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Sharpmaker in action. Just stroke straight up and down.
The downside to the Sharpmaker is that if you swipe the knife off the stones while using the corners
you can round the tip. This is easily remedied by taking your time and sharpening in two stages, one
for 90 percent of the edge and a second stage concentrating on the tip only.
Even though I have the EdgePro I still use my Sharpmaker regularly. It is faster to set up for quick
touchups.
Pull-Through Systems
There are a number of gadgets with hones (usually tungsten carbide bits or wheels) that meet to
form a V. You draw the knife through the slot and Presto! instant edge. Ha. Most of these things are
garbage, not even fit to sharpen your lawnmower blades. Repeated use of one of these  sharpeners
will chip the edge of your kitchen knives. No relief is ground into the blade, so it will gradually
become harder and harder to sharpen.
To show that there are exceptions to every rule, the Henckels Twinsharp with its ceramic wheels
doesn t do too much damage and can be used for quick touchups though judging which set of
wheels within the slot you are using can be a little tricky.
The Chef s Choice Model 450 uses diamond stones at the same angles (22.5 and 25 degrees) as the
final two stages of their electric sharpeners. If you own a Chef s Choice 110 electric sharpener, this
pull-through gadget is handy for touchups between sharpenings.
According to Steve Bottorff, there is even one gem among all of the gadget dross.
 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
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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 Sharpeners
Please promise me that you will never use the knife sharpener on the back of your electric can
opener. Please?
Electric sharpeners grind very aggressively and can remove a lot of metal in a hurry. You can turn
your chef s knife into a filet knife with just a little inattention. Using a bad electric knife sharpener is
just about the worst thing you can do to your knives. Poor electric sharpeners have given the entire
genre a bad name. The better machines are multi-stage and use a slower grinding method.
Just as with the pull-through sharpeners, there is a gem among the electrics. Both Steve Bottorff
and Cooks Illustrated rated the Chef s Choice model 110 as the best electric sharpener available. It
puts a very nice edge on knives, sets a back bevel for performance and doesn t remove metal at an
alarming rate. It does have a tendency to scratch the blade, however.
The $85 Chef s Choice Model 110 uses 3 sets of diamond hones. Each sharpens at a different angle.
The first stage is very aggressive and puts an approximately 15 degree back bevel on the knife. 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.
If you must have an electric sharpener, this is the one to get. Heck, for $85 I might pick one up
myself.
The Chef s Choice 110 has a big brother, the EdgeSelect 120 model, an upgraded version of the 110.
The EdgeSelect 120 features a polymer strop as its final stage, producing a razor sharp edge.
Professional Knife Sharpening
If you ve read this far, you are a sharpening professional
If you want to send your knives out to be sharpened, that s fine, but remember, finding a good
sharpener is like finding someone to cut your hair. It s somewhat hit or miss. Just because they have
a sign on the door and a grinder in the back doesn t mean that you ll get exactly what you were
expecting.
Now that you have a little more knowledge at your disposal, you can at least make an informed
judgment about what you want from your professional sharpener. Can he sharpen to specific angles?
Does he charge extra for a back bevel? Is he willing to grind a 15/20 double bevel that you can
touch up yourself? What grit does he finish the edge with? You are now an educated consumer.
Fat Guy has a place he recommends. I don t have any experience with them, but I ll take his word
for it.
Section Eight: Conclusions and Resources
There you have it. The veil has been parted and you ve seen that the man behind the curtain really
doesn t have anything special going for him. This is stuff that anyone can do with a little knowledge
and a little practice. Sharpening your own knives can be extremely rewarding. You can establish a
Zen-like communion with your knives.
Just remember the basics  burr, angle, abrasive, consistency and strategy. Do not ever let anyone
tell you that sharpening is too hard or too complicated to do yourself. Most recipes could be seen
exactly the same way. They re complicated. They require knowledge and technique. They re a little
scary. So what? You d be insulted if someone told you that a particular dish was beyond your
abilities. At the very least you d be righteously indignant. You should feel the same way the next
time someone suggests that you send your knives to a  professional.
And just like cooking, you become better and better by doing. Your first attempt might not be
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perfect. But it will be your achievement. No one else s. And it just gets better after that.
Resources and Links
Obviously, even as verbose as this tutorial is, I ve missed a few things. Hopefully we can cover any
glaring absences in the Q&A session. But if you read this tutorial, print it out and have it on hand the
next time you decide to sharpen your knives, I have no doubt that you can create an excellent edge,
better than anything you ve been able to achieve before. Because of me? No. Because of all of the
people I ve stolen from :P.
Some of those people who answered questions, provided assistance and generally kept me from
making a fool of myself:
Joe Talmadge, author of the http://www.bladeforums.com/features/faqs.shtml. Much of what I know
or have learned about sharpening is influenced by or just plain stolen from Joe s work. So if there
are any truly egregious errors, it s his fault. Joe was very generous with his time answering some of
the questions I had in writing this tutorial.
Ben Dale, owner of http://www.business.gorge.net/edgepro/.
http://www.physics.mun.ca/~sstamp/knives/reviews.html, graduate student in physics in the field
of collision induced absorption at the Memorial University of Newfoundland. He is a dedicated knife
nut and knife tester. Some of his findings are controversial in the knife world, but Cliff knows his
stuff.
http://www.haslinger-knives.com/, Canadian chef and knife maker. He makes gorgeous chef s
knives.
Sal Glesser, president of http://www.spyderco.com.
Murray Carter, ABS Mastersmith. Upon completing his apprenticeship under the tutelage of a 16th
generation Yoshimoto bladesmith, Murray was asked to take the position of number seventeen in the
Sakemoto family tradition of Yoshimoto Bladesmithing. He is the only Caucasian to ever have had
the honor and privilege of this position. He makes some of the best Japanese kitchen knives
available.
The members of http://www.bladeforums.com. Seventeen thousand of the most knowledgeable and
contentious knife nuts on the planet. If it s pointy, they ll argue about it. Just about any question
you might ever have about knives or sharpening can be answered by searching Bladeforums.
Additional Reading
The Razor Edge Book of Sharpening, John Juranitch. A little outdated and somewhat of a commercial
for Razor Edge products, this is nonetheless a good primer on sharpening.
Sharpening Made Easy, Steve Bottorff. This slim book is a good starting point if you re just getting
into sharpening. Give it as a gift (along with this tutorial) to the sharpening-challenged.
The Complete Guide to Sharpening, Leonard Lee. Deals mainly with sharpening woodworking tools,
but has a great discussion on the principles and mechanics of sharpening. Also has very good
information on using power grinders and sanders to sharpen, if you re the handy type.
Sharpening with Waterstones, Ian Kirby. Mostly for woodworkers, but more information on
waterstones than many other sources.
The Professional Chef s Knife Kit, Culinary Institute of America. Weak on sharpening, but a great
resource for kitchen knife information and basic knife cuts.
Where to Buy It
Here s where you can pick up all the cool stuff mentioned in the tutorial.
http://www.leevalley.com. Abrasives, waterstones, strops, honing compounds and some of the
coolest woodworking and gardening tools in the known universe.
http://business.gorge.net/edgepro/. EdgePro Apex and Professional sharpening systems,
replacement stones and fine grit ceramic rods.
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http://www.newgraham.com. Spyderco Sharpmaker 204.
http://www.razoredgesystems.com. Guides, stones, Razor Edge Book of Sharpening, sharpening
video, Edge Tester and Mousetrap Steel (an amazing tool for restaurant-volume knife maintenance).
http://www.japanese-knife.com. High end Japanese knives. If you want to spend a couple of grand
on a gyotou or yanagi-ba, this is your place. Also has waterstones.
http://www.handamerican.com. Smooth steels, strops, honing compounds, etc.
http://www.knifecenter.com. Discounted kitchen cutlery, Lansky and Gatco sharpening systems,
DMT diamond stones.
http://www.1sks.com. Kitchen knives and sharpening equipment. Helps support Bladeforums.
http://www.kellamknives.com and http://Http://www.bladeart.com. Two of the very few places you
can get Murray Carter s knives in the Western hemisphere.
Instructor: Chad Ward
Chad Ward is a freelance writer and marketing strategist based in Wichita, KS. His articles have
been featured in magazines ranging from Flatpicking Guitar to Manufacturing Engineering. He is also
a knife collector and dedicated home cook.
Copyright 2003 Chad Ward. All rights reserved.
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