Crossed Heart Forge

Charcoal forged classical tanto & fusion style takedown knives crafted by hand from reclaimed steel and natural materials using traditional techniques.

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Behind the Scenes: How Tanto Are Made

Making Charcoal from Scrap Wood

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
The best forge fuel for high carbon steel tanto is softwood charcoal. The raw material is scrap wood from local sources such as furniture makers, carvers, and foresters.

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
The charcoal kiln is loaded, the door is put in place, the fire is tended for several hours until the steamy smoke changes colour, and then it is completely sealed until it cools down.

Island Blacksmith: Charcoal forged knives reclaimed from harrow teeth.
After completely cooling the kiln is opened and the charcoal can be chopped and sorted into grades of bladesmithing charcoal and heat treating charcoal. (Watch charcoal chopping.)

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Finding the Raw Materials

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
The blade steel is mainly curated from old homestead piles, this one formerly belonging to a blacksmith and farmer. Old farm equipment and carriage spring steel make great blades.

Island Blacksmith: Charcoal forged knives reclaimed from harrow teeth.
Potential blade steels are tested using several methods to determine their suitability and the best approach for heat treatment. The older, lower alloy steels are preferred by our inspectors.

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Carbon steel takes and holds a great edge and responds well to traditional water and clay yaki-ire hardening. These carriage springs may be well over a century old. (Watch the disassembly.)

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Forging the Blade from Reclaimed Steel

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
The elemental simplicity of a brick charcoal forge supplied with air from a hand powered wooden fuigo box bellows forms the starting place for the shaping of a blade.

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Most of the shaping can be done with well-placed blows from a hand hammer. Accurate forging makes the quickest and most efficient use of an entire piece of reclaimed steel.

Island Blacksmith: Charcoal forged knives reclaimed from harrow teeth.
A well forged piece is very close to its final size and saves time and waste when hand filing to final shape. A sen scraper and files are used to refine and true the form. (Watch some forging.)

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Hardening & Tempering the Blade

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
The traditional yaki-ire hardening method using natural clay, charcoal, and rainwater can be risky but produces a hard cutting edge and a tough spine within a single piece of carbon steel.

Island Blacksmith: Charcoal forged knives reclaimed from harrow teeth.
After the clay layer has dried, the blade is slowly heated to the colour of the august moon and then plunged into water. The exposed edge cools more quickly and forms a very hard steel structure.

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
The body and spine of the blade cool more slowly and form a very tough steel structure. The rough stone finish on this blade reveals the temper line between the two areas. (Watch yaki-ire.)

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Making the Fittings

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Reclaimed copper from electrical bus bars is very pure and forges well. Other materials include wrought iron salvaged from the sea, reclaimed brass door plate, and scrap copper water pipe.

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Because the entire knife is held together with a single bamboo peg in the style of classical tanto, each metal and wood component must fit accurately on the tang of the blade.

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
The copper components are allowed to develop a fire patina or given a traditional rokusho style patina and then finished with buffed ibota wax or tung nut oil. (Watch making a habaki.)

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Making the Handle & Scabbard

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
The inside of handle and scabbard must fit the tang and blade precisely before the halves can be joined together with sokui (rice paste glue). (Learn about sokui.)

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Once the halves are rejoined, shaping and finishing the exterior of the Hounoki core is done with Japanese hand saws, planes, chisels, rasps, and kiridashi knives.

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Each component is carefully carved, shaped, and fit together to provide strength and make best use of the natural properties of each material. (Watch a tanto mounting being carved.)

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Lacquering with Natural Tree Urushi

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
The first layers of urushi lacquer are applied thinly and wiped off to seal the wood until fully cured. Each layer is cured for several days and then polished before the next is applied.

Island Blacksmith: Charcoal forged knives reclaimed from harrow teeth.
For an ishimeji stone finish, crushed dried tea leaves are sprinkled into the wet urushi. After curing for several days, the tea leaves are sealed and strengthened with more lacquer.

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Once the lacquer has fully cured, the fixed components are attached using kusune (pine resin glue) or a mixture of urushi and sokui, called nori-urushi. (Watch a tanto being lacquered.)

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Final Assembly

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
A full tanto mounting may contain ten or more parts made from twenty or more components. Most of the parts are fit together only by friction and locked in place by the bamboo peg.

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
The major components of handle and scabbard are assembled. A combination of wood, rawhide, and tightly wrapped leather or cord strengthens the handle assembly.

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Once all of the fittings have been built, the blade is given its final polish using fine natural Japanese waterstones and finger stones. (Watch a tanto being assembled.)

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“My approach as a craftsman is to work within the creative constraints of the classical tanto form and nihonto handle mounting technology, building on a foundation of Japanese swordsmithing aesthetic and technique.”

see the finished work tour the workshop

Case Studies

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Process archives and videos

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Mountain Kotanto

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Mountain Tanto

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Outdoor Knife

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Touzai Tanto

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Kuromon Aikuchi Tanto

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Tsukimi Tanto

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Uzumaki Kotanto

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Tanto Blade (forging)

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Yaki-ire (hardening)

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Togi (polishing)

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Habaki (blade collar)

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Tsuka (handle)

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Saya (scabbard)

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Koshirae (full mounts)

Island Blacksmith: Charcoal forged tanto, reclaimed steel.
Shirasaya (storage scabbard)


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