Combat Knife
Selection: Science in Action
by Kevin McClung of
Mad Dog Knivestm
When faced with the bewildering array of
factory, custom, and "factory custom" knives available today, one might very
well wonder exactly how to penetrate the smoke and mirrors barrage of mysterious alloys,
remarkable claims and seemingly amazing performance possibilities. True, I make knives,
but I am not so arrogant as to believe that I am the only maker capable of building a good
knife. I teach knife fighting techniques and wilderness survival with a knife as the
primary tool. During my experiences, and by watching my students, customers, and other
knife professionals, I have developed a set of parameters to determine appropriate
combat/utility knife selection. Please note that all of these conclusions are backed up
with careful explanations. If a maker or manufacturer is unable or unwilling to answer
specific questions about performance parameters and back up their answers, the quality of
their product must be suspect.
1.) Regardless of its relative strength, a
blade should break rather than remain bent. Bent blades are virtually impossible to
straighten. Bent blades cannot be returned to their sheath. Bent blades are severely
impaired in function. Broken blades can still be utilized in a variety of ways, either by
re-hafting them or simply holding the sharpened edge in your hands as our knuckle dragging
ancestors did. The fragments can still be carried in the sheath and need not be bothered
with otherwise. Ask any samurai - would he rather his sword break or bend if it failed?
Invariably, the choice is a break. Bent knives are useless knives. Broken knives are still
nominally useful.
2.) The user must be electrically isolated
from the blade. Since electricity is so prevalent these days, the chances of needing to
cut a wire, cable, or com line that has power on it are extremely high. Having personally
blown my butt off by cutting into supposedly cold line (440V @ 50 amps) using a full tang
knife, I can tell you in no uncertain terms that this is an experience that you DO NOT
want to have. Knives with hidden full tangs offer excellent strength and electrical
safety, if they utilize electrically insulative grip material (G1O, nylon, etc. Kraton®
is not recommended as a dielectric insulator).
3.) The grip must be comfortable in any
position that the knife is held. A knife is very dynamic in use, and when used properly
must move around in the hand. All surfaces should by rounded so as to never bite or wear
the hand. Finger grooves and sub hilts are orthopedic liabilities and should be avoided,
lest one face damaged finger tendons and bruised knuckles. Other tools with use modes
similar to knives would be considered ridiculous with the addition of those features.
Imagine a scalpel with a sub hilt . . . a hammer with a slab sided, finger groove grip.
Not very likely to be a useful tool, you say?
4.) Saw teeth are more of a liability than an
asset on a knife. There are a number of lightweight pocket saws on the market. If you feel
that you must have a saw, there's your answer. Saw teeth hang up on sheaths, provide high
stress areas, particularly if they are not radiused at the bottom, and seldom, if ever,
work well. Witness the now defunct Phrobis C.U.K., and others of this genre. Perhaps the
silliest thing I have seen lately are the knives with "saw teeth" cut into a
hollow grind. The depth of their cut in stiff material is intrinsically limited to the
depth of the tooth, about 1/8 of an inch. Why bother? Yet somehow the addition of this
questionable feature adds to the cost of the knife. One must deduce that this is intended
to discourage one from purchasing an overpriced, badly designed product. With this in
mind, I hereby request all manufacturers of sawtooth equipped knives to double their
prices immediately. Holes or slots in the blade are also a major drawback. Major causes of
spring failure are holes, slots (nicks) and deep tooth marks. Since a knife is basically a
leaf spring with a sharp edge, intentionally installing holes or slots in a blade is just
begging for trouble. (See Machinery's Handbook, 22nd edition, Page 432, Table 21, Group 1,
Paragraph 3, "Causes of spring failure.")
5.) The grip, and other components of the
knife (adhesives, loctite, blade coatings), should survive immersion in boiling water and
common solvents like gasoline, D.E.E.T., etc. without retaining any solvents or degrading
in any way. Boiling is necessary for sterilization, immersion or splashing in solvents is
commonplace during refueling, scavenging, and application of D.E.E.T. Handle materials
that pass these criteria include G10, G11, Zytel®, and some of the harder (90A
durometer) Kraton® grips. Handle materials that fail these criteria include some of
the most common materials used on "combat knives": Paracord - soaks up gas like
a sponge; Micarta - soaks up gas; Hypalon® - degrades and falls apart on contact with
gas or D.E.E.T.
6.) The blade, guard, and grip must be bonded
together water tight. Ideally, in the case of metal guards, the guard will be silver
soldered to the blade, and the grip is permanently epoxied to the tang and guard with no
gaps. This keeps corrosives, bacteria, and other gook out of the knives and simplifies
maintenance and sterilization dramatically. Super glue and other cyanoacrylate adhesives
should not be used as they have a marked tendency to degrade upon contact with water
(especially hot water) and solvents.
7.) The blade should hold an edge well, and be
large enough to perform the tasks required of it. Edge holding ability and cutting
performance are a can of very wiggly worms, and subject to wide interpretation. One must
test a knife oneself to be thoroughly satisfied. In short, if you haven't actually seen
the knife in question perform to your satisfaction, don't believe that it will do what
you've seen in a picture.
8.) Contrary to the dogmatic beliefs of some,
forging and stock removal have no significant advantages over one another. All modern
steels undergo forging during their processing, so heating it and beating it does not
necessarily mean that the knife will cut better. Proper heat treatment and high quality
steel are the key to performance, not arcane guild craft and mysterious mud packs.
9.) Be aware of what kind of money and time
goes into the production of a prospective knife. There are a lot of cheap knives
masquerading as expensive ones. Knives with parts that look stamped out probably were. One
"Oregon" knife company, actually owned by a European company, was producing a
rubber handled bowie with the company's name, U.S.A., and Portland, Oregon, proudly etched
on the blade. Nowhere did it say that it was actually stamped and ground in Italy . . . by
the way, this knife featured a Hypalon® handle. Another rubber handled, bowie style
knife we know of retails for between $225-$250. Dealers pay $117 for this same knife, in
any quantity. Dealers buy this knife from sporting goods wholesale distributors who paid
$60-$70 for it. Kinda makes you wonder what it actually cost to ship from the manufacturer
. . .
10.) The sheath must be rigid and cut proof.
Kydex® or molded plastic/fiberglass sheaths will keep a blade from piercing the side
of the sheath during a fall. Unlined Cordura® and leather sheaths are quite simply
inadequate.
Readers should be aware that in writing this
article, I have endeavored to provide an educational service, as opposed to shamelessly
promoting my own goods. I, and others who take the ethical high ground, will not simply
place a call to Seki, Japan and have another 30,000 knives cranked out. I am firmly
convinced that American materials and craftsmanship are the equal of any in the world and
the customer will be well served by educating himself as to the economic implications of
buying knives of foreign origin. Whether your blade choice is a factory piece or custom
made, I urge you to buy American.
¡@
