the edge

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sed 's/^@//' >serrated.vs.plain <<'@EOF'
Author: Joe Talmadge questions@bladehq.com
Last Modified: April 1998

I. Introduction
II. Plain vs. Serrated: The Conventional View
III. Plain vs. Serrated Re-thought
IV. What Should I Carry?
V. Thoughts On The Partially-Serrated Blade

There's been a jump in recent years in the popularity of serrated
edges, and there's often confusion as to when a serrated edge is
advantageous, versus when a plain edge is advantageous. The question
comes up often in rec.knives.

For our discussion, we'll need to talk about what we're doing with the
knife. Think about what you can do with a knife: you can shave,
slice, slash, saw, hack, chop, etc. For our purposes, we'll divide
all knife uses into two very broad categories:

Push cuts: The main cutting is done by pushing the edge through the
thing-to-be-cut. For example, when you shave, you push the edge of
the knife through your beard. When peeling an apple, you push the
edge under the skin of the apple. When chopping wood, you try to push
the edge into and through the wood.

Slicing cuts: The cutting action is substantially done by dragging
the edge across the thing-to-be-cut. When you slice meat or a tomato,
you drag the edge across the tomato as you cut through it. Slicing
and sawing are examples of slicing cuts.

In general, the plain edge is better than the serrated when the
application involves push cuts. Also, the plain edge is superior
when extreme control, accuracy, and clean cuts are necessary,
regardless of whether or not the job is push cuts or slices.

In general, the serrated edge will work better than the plain edge for
slicing cuts, especially through hard or tough surfaces, where the
serrations tend to grab and cut the surface easily. Some of the
cutting power of the serrated edge is due to its format alone; thus,
even a dull serrated edge knife will often perform competently at
slicing jobs.

The plain edge will work better for applications like shaving,
skinning an apple, skinning a deer. All those applications involve
either mostly push cuts, or the need for extreme control. Serrations
work really well on things like tough rope or wood, where the
serrations bite through quickly.

Generally, the more push cuts are used, the more necessary it is for
the plain edge to have a "razor polished" edge. A knife edge becomes
more polished when you move to higher and higher grit stones.
Generally, 1200-grit is considered polished; a 6000+ grit Japanese
water stone would polish the edge further.

One interesting case is cutting a tomato. In theory, you can just
push a blade through a tomato, so a razor polished plain edge would
work fine. However, the tomato is soft, and unless your plain edge
knife is very sharp, the tomato will simply squish when you start
pushing. You can (and many people do) use a slicing motion with your
plain blade, but if it's even a little dull it won't cut well and it
may not even break the skin. Use a sawing motion with a serrated
knife (even a dull one), and your tomato will slice fine.

You will read about test after test where the above view is
confirmed. That is, the plain edge excels in push cuts, and the
serrated excels in slicing cuts. This confirms the conventional view
@... to an extent.

Since actual tests confirm the truth of the conventional view, what
more is there to be said? The problem is that the tests are often not
as thorough as they need to be. That is, when testing plain
vs. serrated performance, most tests are comparing a plain polished
edge to a serrated edge. Given that, it is no surprise that the
serrated blade easily outperforms the plain blade when cutting (for
example) rope.

A polished edge is not the only choice with a plain blade. One can
get the plain edge to perform much differently when sharpened with
coarser stone. People who cut rope often use a plain edge sharpened
on a file, to get an incredibly coarse, "micro-serrated" edge that
performs wonderfully at slicing jobs. So the knife testers are
testing with polished plain edges, whereas people experienced with
cutting rope use coarsely-ground plain edges.

Whether or not serrated blades will out-slice coarse-ground plain
blades seems to depend on the medium being cut. Harder materials (or
materials under tension) do well for serrated blades. With softer
materials, the serrations will sometimes catch and unwind the material
rather than cut -- in this case, coarse-ground plain blades may easily
out-slice serrated blades.

So the claim that serrated edges work better than plain edges for
slicing needs to be re-examined. It appears that as materials get
harder or put under more tension, the serrated edge may slice a bit
better than a coarse-ground plain edge. As the material gets softer
and looser, the coarse-ground plain edge may slice a bit better. And
as we go towards push cuts, the polished plain edge comes into its
own. The user may want to experiment on those materials that he often
cuts, before choosing the edge format.

In addition, keep in mind that the coarse plain edge is much easier to
sharpen than the serrated edge. Just grab your file or extra coarse
stone, take a few swipes, and you're ready to go. With the serrated
blade, you'll need to find a sharpening rig with the special serrated
blade sharpener. Balancing this is the fact that serrated blades need
to be sharpened less often.

Should you carry a serrated blade or plain blade for everyday utility
carry? Unless you *know* that the majority of work you'll be doing
heavily favors slicing or pushing (e.g., "I spend all my time
whittling"), it may not matter much. My experience has been that
general utility work is usually general enough that either format
works just fine, though these days I tend to lean towards plain
blades. Also keep in mind that by changing your sharpening strategy
on the plain edge, you can significantly change its characteristics.
If you do a lot of push cutting, you want to go with a razor polished
plain edge. If you do a lot of slicing, you'll need to decide between
a coarse-ground plain edge and a serrated edge. I don't mind
sharpening, so I lean towards plain blades, strategically sharpened to
the right grit (polished or coarse) for the jobs I happen do be doing.

Occasionally, people mention that the serrated edge looks intimidating
to the masses. This could be good if you're using this knife
primarily for self defense and want an intimidation factor. Or it
could be bad, if you're carrying for utility work and don't want to
scare people (especially the nice officer who pulled you over for
speeding and asks to look at the knife in your sheath). Rumor has it
that airport guards are particularly strict about serrated edges.
Other than at airports, I don't think the menacing appearance of the
serrated edge is important enough either way to affect what I carry.

Another option is the combination plain/serrated edge. This format
appears to have overtaken the all-serrated format. Typically, the
50%-60% of the blade nearest the tip is plain, while the back 40%-50%
is serrated. There are mixed feelings on this format. Many people
swear by this format, and feel that it is a good compromise, giving
the user the choice of precise push cuts from the plain edge, and the
advantage of the serrated edge for tougher materials. However, keep
in mind that on a 3.25" blade, there's maybe 1.25" of serrations. The
detractors of this format feel that 1.25" is too short a length for
the serrations to be really be useful, and the length of the plain
edge is being sacrificed for no good gain.

My own philosophy on partially-serrated blades at the moment is that
since I have both edge formats in one knife, I try to let each one
shine in their respective areas. So I'm razor polishing the plain
edge part, often on a 1200 grit diamond stone or even 6000 grit
Japanese water stone, and then stropping it. The plain edge is scary
sharp for push cuts, and I use the serrations when I need to cut
through hard or fibrous material.

Partially-serrated blades are often serrated at the "wrong" place.
For example, for camp use, I might want the belly serrated for cutting
my steak, and the part near the handle razor-polished for whittling
and control-type usage. However, 99.9% of partially-serrated blades
are ground exactly the opposite: the ripping inaccurate serrations are
at the control part of the blade, and the plain part is out at the
slicing part.

In theory, one can use a plain blade to get similar performance to a
partially-serrated blade. Just razor polish the plain blade, and then
rough up one part of the edge on a file, to get a knife that will
excel at push cuts at one point of the blade, and excel at slicing
cuts at another.