The core of this project is a charcoal-forged 1965 Series 2a Land Rover leaf spring steel blade, water quenched with clay and sharpened with waterstones, an outdoor knife that has the foundation of the Japanese sword but is finished in the simple and humble style of farming and foresting tools of centuries ago.
Satoyama are the managed forest areas that border the cultivated fields and the mountain wilds in Japan. Historically they provided soil nutrients, firewood, edible plants, mushrooms, fish, and game, and supported many local industries and crafts such as farming, timber construction, and charcoal making. The interaction of forest, arable land, wetlands, and streams are an important component of the satoyama landscape.
The subtle and rustic appearance of hammer marks on the blade and hand-carved wooden handle finished with natural urushi lacquer made from tree sap—reminiscent of hand-hewn beams in a kominka farm house that are darkened by years of smoke drifting up from the irori hearth. A hand crafted tool for adventure that would be very much at home in the field, forest, or mountain landscape.
Forged from a reclaimed 1965 Series 2a Land Rover leaf spring, the wider blade profile of the mountain style kotanto is based on a kamakura sword and has more pronounced belly with slight drop point. The temper of this high carbon steel blade has been left relatively hard in order to hold a keen edge for tasks such as wood carving and hand work. This particular combination of steel and heat treatment is well suited to users who require a good edge and are willing to take care of it.
The tang is constructed in a similar manner to a Japanese sword requiring only a single bamboo peg to hold the knife assembly together. In addition to the sense of beautiful simplicity, this design allows the knife to be taken apart for cleaning, polishing, detailed cutting tasks, or major resharpening work.
The generously-sized but comfortably narrow handle and accompanying scabbard are carved from local magnolia and finished in traditional fukiurushi lacquer in a very slightly textured finish which assists with grip. A forged brass seppa and natural cord wrapped ferrule accents the handle and the removable peg is carved from susudake, a piece of bamboo that served for a century or more as part of the ceiling or roof in a kominka, darkened and hardened by decades of smoke wafting up from the irori hearth.
The blade is 4.5″ long, the overall length is 9″, and just over 10″ when sheathed. The spine at the munemachi is about 5.5mm thick.
Katachi (geometry): hira-zukuri, kaku-mune (squared spine)
Hamon (edge pattern): rising suguha
Boshi (tip pattern): maru
Nakago (tang): futsu, kiri-jiri, one mekugi-ana
Mei (signature): mumei (unsigned)
Koshirae (mounting): satoyama aikuchi style, issaku
Materials: reclaimed Series 2a Land Rover leaf spring steel, brass doorplate, Magnolia, natural cotton cord, natural urushi lacquer, susudake Bamboo
Process
This knife was forged and underwent yaki-ire at the museum forge. It began as a section of leaf spring from a 1965 Series 2a Land Rover, which seems to be listed as 60sicr8 steel and has not changed formulation since 1948 when the very first series 1 Rover was built.
Ready for a day at the museum forge, the old 1966 Rover still earning its keep hauling tools overland at almost 60 years running (and on its original springs).
A load of several hundred pounds of tools ready for a day at the forge.
Opening the forge and preparing to unload the tools and steel.
This knife began as a section of leaf spring from a 1965 Series 2a Land Rover, nearing the end of its useful service life on a vehicle that was undergoing restoration.
A cold chisel was used to separate the leaves of the spring.
The leaves are cleaned of the deepest pitting, cut and sorted by size and condition before forging to shape on the anvil.
The charcoal swordsmith style forge with hand-powered wooden box bellows is used to heat the steel as it is forged.
View across the forge and out to the forest between heats on a cool and cloudy spring morning.
After a few hours the steel has been forged almost entirely to its final shape using a hand hammer.
A small amount of hand filing forms the notches and cleans up the spine and tang, completing the profile.
A sen-dai (staple vise) holds the steel flat while the edge is adjusted with a file to an even 1mm thickness and then smoothed with a coarse stone.
After some final straightening and cold adjusting the steel is ready for hardening with a traditional swordsmithing technique.
A mixture of natural clay, charcoal powder, and polishing stone powder is prepared with water.
Adding the thin clay layer to delay the cooling of the body of the blade during yaki-ire (hardening).
After the clay dries, the steel is heated carefully in the forge to the lowest possible red-hot critical temperature and plunged into water to cool quickly.
It has survived the stressful process of yaki-ire. Due to the differential cooling rates the strip along the edge is now very hard while the rest of the blade remains tough and ductile, the best of both realms.
A seppa (blade washer) cut from an annealed reclaimed brass door push plate using hammer, chisel, and shears.
The opening for the blade is cut out with a chisel and filed carefully to fit the tang.
After final fitting and coining the edge in edo style the seppa is ready for service.
A batch of Rover steel blades receiving various fittings in preparation for mounting.
Wood working in the coastal forest, Arbutus leaves continue to fall all year long!
Hauling woodworking tools in summer mode, no need for a roof for a couple of months.
The best kind of air conditioning is outdoors!
A block of locally sourced Magnolia will become both the handle and scabbard.
Carefully hand sawing the block in half after marking a half-line all the way around.
Planing the inside of the block halves with an antique kanna.
Planning the best location and angle of the division between handle and scabbard.
Removing a small wedge to allow the grain to sit in the best orientation for both handle and scabbard.
Choosing the final blade location within the wood blocks based on the final shape concept.
A rough visual pencil guide is drawn on omote (public) side and then a precise one is cut next to the steel using a kiridashi knife.
After careful carving the omote side of the handle fits snugly and already holds the tang in place on its own, even when turned over.
The interior of the omote side of the scabbard nearing completion, maintaining alignment with the handle.
Making final adjustments to the handle and scabbard fit on both halves.
The interior carved and ready for fixing back together using hide glue, it will cure for a week before further work.
After curing, excess wood is removed with kanna (handplanes), from four sides to eight sides to sixteen and so on, and the handle and scabbard is roughly carved with a kiridashi knife to form based on classical tanto lines.
The final design decisions are to cut to length and shape the pommel and the tip of the scabbard.
A thin kiridashi knife is used to create subtle sculpting to all areas of the handle in the style of a classical tanto.
The placement for the mekugi-ana is chosen and drilled through the tang using an antique hand-cranked post drill.
The mekugi (retaining peg) is carved from susudake, bamboo that has spent the greater part of a century as part of the ceiling or roof inside a kominka farmhouse, darkened and strengthened by the smoke from the hearth.
Completed mountings ready for lacquering and finishing, carving facets will be left in place for a rustic look.
Lunch break view towards the forge, toolboxes and tools must be onboard for whatever may be required on a given day.
Late fall sunlight still bright at midday but shadows are lengthening as the museum season comes to an end.
The first application of natural fukiurushi seals the wood in preparation for following layers, it is cured slowly in a slightly warm humid muro/furo box, each layer takes 1-4 days to cure. Natural urushi lacquer is made from the sap of a certain tree, evaporated, fermented, and filtered.
After the first few thinly applied and textured layers have cured the cotton reinforcement cord is tied tightly in place and then saturated with urushi.
Final stages of lacquering after several layers have been built up to the appropriate texture and colour. Next the handle and scabbard will sit at room temperature and humidity for a couple of weeks to finish curing while moisture stabilizes.
After a couple of weeks to allow the wood moisture levels to stabilize after lacquering, final adjustements to the fit are made. The blade is finally sharpened and the knife is ready for assembly.
