"Xanthid" (Reef) Tactical/Working
Marine Grade Dive Knife
- Size: Length overall: 12.0" (30.5 cm), Blade Length: 6.5" (16.5 cm), Thickness: .200" (5.1 mm)
- Weight: Knife: 6.1 oz. (173 grams), Sheath: 8.7 oz. (247 grams)
- Blade: Böhler N360 ISOEXTRA® nitrogen stainless tool steel, hardened and tempered to Rockwell C57, mirror polished and passivated
- Sheath: Hybrid tension or hybrid-tension cam-lock in kydex, anodized 5052H32 aluminum, blackened and passivated 304 stainless steel, anodized 6AL4V titanium
- DCAM (Dive Calf Accessory Mount): Neoprene foam, nylon elastic, bonded polyester, ABS plastic
- Weight: 8.6 oz. (244 grams)
- DBAM (Dive Belt Accessory Mount): Neoprene foam, nylon elastic, bonded polyester, ABS plastic
- Weight: 6.0 oz. (170 grams)
- Knife: "Xanthid" is the family of crustaceans
composing the most toxic and deadly crabs in the sea. It also
has a more common name for the pattern, "Reef." In some rare cases,
because I make so many knives and patterns, some knives end up with
two names! Made
with input from counterterrorism and dive professionals, the Xanthid is designed as a dedicated
tactical and working dive knife, made completely for wear in the salty
marine environments encountered in the ocean. It is an ultimate
dive knife, built for long lasting durability, light weight, and
serious use.
- The steel for this knife had to be very special,
suited for the task and exposure like no other. The steel is a
unique one, an ultramodern, premium, super-clean, refined steel,
designed for high hardness and wear resistance and incredible
corrosion resistance. Most martensitic stainless steels can corrode
in long term exposure to marine environments, so dive knives are
often made with metals that have high corrosion resistance like
titanium and austenitic stainless steels. Both of these metals are
soft at their highest possible hardness, dozens of times softer than
a knife blade should be. This is fine for scraping around a coral
bed or cutting some monofilament, but titanium and austenitic
stainless steels are not hard and tough enough for heavy
working or combat duty. They
simply will not hold an edge, and are pliable and weak. Böhler,
a German foundry, has developed N360 with a totally different and
refined processing method. This method results in an incredibly
corrosion resistant tool steel, a true tool steel, that is hard and
tough and durable with extremely high corrosion resistance not found
in other stainless steels, even in high chromium 440C. Simply put,
this steel has the highest corrosion resistance currently available
for a functional, durable, and reliable knife blade. More about this
premium modern alloy
at this link
on my Blades page.
- The blade design reflects the geometry of
some of my best tactical and working knives, with some unique
features.
The blade of the Xanthid is double-edged and hollow ground; the main
cutting edge is hollow ground with a 3" diameter wheel and the top
edge with serrations is hollow ground with a 3" diameter wheel. The
main cutting edge has a substantial recurve area, for a double concave
geometry that is sharper than any other edge grind, literally sharper
than a straight razor, which is, after all, straight! This entire knife
has an extremely difficult grind profile, and the purpose is to
create two complimentary edges, both yielding extremely thin and
razor keen edges with a high longevity while preserving a good
cross-sectional thickness of center spine to support thrusting and
the point. The point of this knife is critically strong,
with the top grind based on a
very ancient design called "armor piercing." This is not for
piercing today's armor, but for piercing chain mail of old:
interlocking metal rings woven into a tough mesh. This
is a point with an interrupted top grind and a full lower hollow
grind, resulting in a thick upper section of the point that
resists breakage, while the main cutting edge is razor keen to
the tip. This makes for a very strong penetrating point, resisting any
tough or hard materials encountered, whether fish, foe,
or working task. The strong point grinds are well-matched and supported
by the full thickness spine running down the center of the blade.
The main cutting edge is very thin and sharp as a straight razor; the top edge is designed
with my Hammerhead serrations, which are extremely tough and
aggressive, with reduced snagging with wide transitions between
concavities and segmented edges. The blade is hardened and tempered
to RC57 for maximum toughness (resistance to breakage) at high
hardness (wear resistance). The grinds on the blade are accurate,
sweeping, and with nicely radiused grind terminations for great
transfer of energy without stressing the blade-to-handle ricasso
area while a very long supportive spine runs the length of the
blade. The extremely high polish of the N360 tool steel further
enhances the cleanliness, corrosion resistance and serviceability of
the knife.
- The handle of the Xanthid needed to be light, highly
corrosion resistant, as comfortable as possible, and secure as
possible under the salty and corrosive environments of the
ocean. The handle is skeletonized, so there is no place
for corrosive salt to hide, be trapped, or attack the steel. It is
designed with an oversize rear finger ring for grip security
and a deep quillon that keeps the hand off the blade. The handle
also has a
long, tapered milling that allows the handle to aid in rudimentary
tasks (like breaking the tightness of a marine shackle or nut). The
rear finger ring aids in forward or reverse grip and allows
quick attachment of lanyard for security. All surfaces are rounded,
contoured, polished and smoothed for as much comfort as possible on
this type of skeletonized handle. The knife feels light yet
extremely aggressive in the hand. This is a tough, serious tactical
and working dive knife made just for the seas, open ocean and
all waters.
- Sheath: The sheath is an evolution of one of my hybrid
tension-locking models, originally made for my skeletonized knives,
but specially adapted to this underwater application.
This is a proprietary design, the best possible sheath of its type
available in the world today. Actually, it is the ONLY type of this
sheath available in the world today! The sheath is built of double
thickness (.125" thick) kydex (methyl acrylate and polyvinyl
chloride) over a welt-frame of anodized 5052H32 corrosion resistant high
strength aluminum alloy.
- Anodized Aluminum Throughout: in order to increase the corrosion
resistance of this alloy, I've fully anodized the aluminum welts.
This means that during the construction, these hand-machined parts
are completed and then anodized for the ultimate corrosion
resistance and durability. The parts have the nearly ceramic-hard
surface treatment on the outside, the inside, and even through the
bolt holes securing the kydex and the machine screw parts! They are
as salt water resistant as they can possibly be, necessary for this
critical application. More about my sheath and component
aluminum anodization at this link.
- Grayed and Passivated: To increase the corrosion resistance of the austenitic
stainless steel hardware and fixtures, the stainless is darkened (grayed)
and passivated. The darkening reduces the flare and reflectivity
of the part and the passivation treatment assures that the most
passive (corrosion resistant) stainless surface possible is
employed on these fasteners. The mottled gray appearance is due
to the darkening and passivating steps, and the stainless is
extremely corrosion resistant.
- Two Retention Methods: The sheath
has two optional retention methods and in either
circumstance, the knife stays locked in the sheath, and
the assembly can trustfully be mounted upside down or
used in highly active underwater movement with relative
security.
- The first retention method is my hybrid
tension-locking mechanism. This device is custom made to fit
each knife, and allows a lock pressure of about 25 pounds to
hold the knife in the sheath, with an optional thumb or finger
release. There are two options to unsheathe: one is placing your hand on the knife handle in forward
(traditional) grip and use the finger or thumb to operate the release
and unlock the knife for a controlled extraction of the
knife. The second is for emergencies, grabbing the knife handle and pulling hard, with at
least 25 pounds of tension, the knife is unsheathed. Please note
that in this particular model of knife, the pull to release
action may cause the hammerhead serrations to contact the
ball-lock, scarring it, therefore, it's for an emergency only!
- The second retention method is my new
hybrid tension-lock cam release. This is a small cam that
when rotated by thumb pressure, releases the tension from
the spring, allowing the knife to be unsheathed without any
contact between the mechanism and the blade. This is
critical for underwater wear, as the eyes may not be able to
see the knife clearly and the hand can feel this mechanism
in position. It audibly snaps open and closed for a good
indicator of release, clearing the hammerhead serrations
during sheathing and unsheathing. The cam-lock mechanism is
all welded 304 stainless steel, darkened and passivated, of
course!
- The titanium used in both
arrangements in anodized 6AL4V, for a darkened blue-gray
appearance, a hardened surface, and extremely high corrosion resistance.
- The sheath (like most of my
sheaths) has die-formed aluminum belt loops that are able to be
moved to multiple locations as well as either side of the sheath
frame. On this particular knife, the belt loops have 8 different
locations with multiple combinations for versatile wear. All of the
components in this proprietary system have maximum corrosion resistance, and the entire assembly is even
reversible by the owner. It's simple, it's lightweight, it's
fast, and it's clean, it's extremely corrosion resistant and it's all
darkened and non-glare.
- The mounts: Since the
bolt pattern of the sheath matches my 2.5" bolt pattern for my
accessories, most of my accessories can be used on this
sheath, including any new ones I develop.
- Horizontal Belt Loop Plates for horizontal belt or webbing wear,
welded for ultimate strength and light weight,
reversible, and in black anodized aluminum.
- Flat mounting straps for rigid clamping to
webbing, belts, or gear in vertical or horizontal
orientation in black anodized aluminum.
- Low profile belt loops
(footman's loops): for tactical webbing belts with
maximum .190" thickness and 1.5" width in black
anodized aluminum
- High profile belt loops
(footman's loops): for tactical webbing
belts with maximum ..250" thickness and 1.5" width
in black anodized aluminum
- Lanyards: Adjustable
550 cord and SCUBA rated, not shown in photos
- All necessary stainless steel hardware, fittings, fasteners and tools for mounting, moving, and adjusting
- Knife/Sheath wear options: A knife is worn, not
carried, so this is critical for a counterterrorism dive knife. In
addition to typical wear positions (on a belt, on PALS webbing, body
armor, or gear and equipment bags, packs, and frames), this knife
has some very specialized wear gear.
See the photos below for the wide variety of mount options
supplied with this ensemble.
- DCAM (Dive Calf Accessory Mount): My client
requested a calf-mounted assembly, one that could be worn
comfortably against the bare skin underwater, stay put while
active, yet keep the razor sharp edge and deadly point of the Xanthid
immediately accessible. I devised a sheath mount rig I
call the DCAM (Dive Calf Accessory Mount). It is constructed
entirely of waterproof dive rated materials, and is secure as it
can possibly be, wrapping around the calf with three strap
mounts of wide, strong webbing. The base is soft, thick 6.7 mm
neoprene foam with textured body-contact rubber on the inside,
and tightly woven nylon on the outside. This is very heavy
wetsuit material, and the mounts for the straps and webbing are
backed with soft Velcro® loop stitch pads to back up the
stitches. The webbing is secured with bonded polyester
waterproof thread, size V-138 for extreme durability. The
outside of the wrap is sealed and bonded with nylon wetsuit
material, stitched with flexible nylon. The sheath tail pocket and
anti-flop shock cord are double thickness elastic nylon; the
tail pocket is three inches deep, and the anti-flop shock strap
is .75" wide. The sheath body clamps rigidly under the center web, and is trapped
between the webbing and the wrap, so is extremely secure. The
buckles are all 1.5" cam lock ABS plastic and are infinitely
adjustable yet can be quickly released in an emergency. This is
a very comfortable rig, and will be a favorite wear accessory in
the future. A video is provided to demonstrate rigging, wear,
donning and doffing of this critical accessory. Photos
below are of "Synan," but the rig is the same.
- DBAM (Dive Belt Accessory Mount): My client
also requested an accessory that allows the knife to be worn in
the middle of the back, with horizontal orientation. This
required the design of the DBAM, Dive Belt Accessory Mount,
which I made of 2" wide polypropylene webbing with ABS buckle,
the same material as the Sternum Harness for my counterterrorism
knife sheaths. The belt is narrowed and fused to accommodate the
width of the span between the flat clamp straps when worn
horizontally, so the sheath clamps rigidly to the belt. The
custom pad is made of the same 6.7 mm wetsuit foam neoprene as
the DCAM, edge stitched and sealed, and held in place with two 3" wide
double thickness elastic nylon straps. The pad stays in place,
protecting the body from the sheath, and it's a comfortable,
secure rig in or out of the water. A video is provided to
demonstrate rigging, wear, donning and doffing of this critical
accessory. Photos below are of "Synan," but the rig is
the same.
- Containers, Instructions, Archival: included are tin plated
steel containers for the fasteners and hardware, and the
instructions for the rig including a checklist and links to unlisted
videos that detail the use, wear, and changing of the components for
a variety of wear options. Included is an engraved co-extruded
acrylic archival plate and a heavy stitched embroidered drawstring
bag.
- Disposition: Counterterrorism, dive tactical,
working
This is a well-designed high durability tactical and working dive knife, made
of the best modern materials available, a truly dedicated weapon and
tool, with the toughest,
sharpest penetrating and working point possible, and one of the finest
dive knives made in the world today, made with the input of some of
the the world's most elite counterterrorism and dive professionals.
Thanks, S.!
