Keeping it Simple with Paracord – Crossed Heart Forge

This special project commemorates a milestone for a long term friend and supporter of the forge and represents another variation of the fusion style outdoor knife genre. The concept is the combination of a western bowie shape made with Japanese techniques, the simplicity and durability of a solid integral cord wrapped handle, and a nata style scabbard with a leather belt frog.

When I started working with paracord for use in survival situations in the early nineties the only source for it in the area was at the surplus store, cut off of old parachutes. Its size, strength, and availability makes it a useful and lightweight addition to an adventure kit. Having a handle or scabbard wrapped and tied with removable cord provides an emergency supply if needed. There is an example of an older project using similar techniques below.

Island Blacksmith: Hand crafted 309 camp bowie made from reclaimed steel using traditional techniques

The blade began as half of a reclaimed heirloom lawnmower blade and was hand forged in a charcoal fire using a mukozuchi sledge, beveled with a tezuchi hand hammer, shaped with files, differentially hardened using traditional water quench yaki-ire, and sharpened by hand with natural Japanese water stones.

The blade is 8.25″ long, overall length is just under 13″, and the overall length of the koshirae is 14″. The 1 x 1/4 inch solid steel handle is wrapped with about 12 feet of paracord. The slightly tapered nata style scabbard holds the blade snugly in either direction, for right/left carry as well as cross-draw and edge-up configurations. The scabbard is wrapped with an additional 18 feet of paracord which can be used as a leg tie or strap down, or removed for use in survival situations.

Specifications

長さ/刃長 Nagasa: 209mm
元幅 Motohaba: 41mm
重ね/元重 Motokasane: 5.5mm
反り Sori: 1mm
中心/茎 Nakago: 117mm
柄長 Tsuka: 117mm
拵全長 Koshirae: 355mm

形 Katachi: hira-zukuri, kaku-mune
刃文 Hamon: suguha
帽子/鋩子 Boshi: ko-maru
中心/茎 Nakago: integral, no mekugi-ana
銘 Mei: mumei
拵 Koshirae: reversible nata style

Material: Reclaimed lawnmower blade steel, Nootka cypress, oak-tanned leather, copper rivets, parachute cord
Date: 2020

This piece is in a private collection in the wilds of Vancouver Island.

Process Highlights

scroll down or jump to the sections below:

Materials
Wakashinobe
Hizukuri
Tsuchioki
Yaki-Ire
Saya

Raw Materials

The raw material for this blade spent several decades as a heavy duty tractor lawn mower blade. A little less than half was used for this knife (top).

The mower blade is stamped “Oregon, 95 039, Made in USA, Grass Side ND”.

Wakashinobe – Forging Out the Bar

Photos in this section taken by Jordan Wende. Striking assistance by Tim of Reforged Ironworks.

The large mukozuchi sledge is used to move the large amounts of material required to upset such a thick bar.

Heavy blows at a higher heat move deeper material and decrease mushrooming.

The bar is forged flat regularly to straighten and correct any warping or mushrooming.

Water can be used on the anvil periodically to clean the forge scale from the surface of the steel.

The bar has become noticeably thicker and longer during the heavy forging stage.

Sunobe & Hizukuri – Forging the Preform & Bevels

The sunobe and hizukuri stages were performed at the museum forge.

A 13lb mukozuchi set up as a simple lever hammer by attaching it to the workbench, allowing it to be used one-handed on the low Japanese anvil. The rest of the rough forging and isolating material for the handle was done with this configuration.

A tezuchi hand hammer finishes the beveling work and handle shaping, here compared to the proportions of the original steel. The thickness has increased from 4mm to a 5.5mm spine, the length from 230cm to 326mm, the width decreased from 57mm to 41mm, and the cutting edge is about 1.5mm thick.

After some filing along the edge and final profile adjustments the blade is normalized to relieve any remaining internal stresses in preparation for hardening.

Tsuchioki – Applying the Clay

A mixture of clay, charoal, and stone powder is blended to the proper consistency.

The thicker layer is about 1mm thick and will delay the cooling of the body of the blade by about half a second, enough to prevent martensite formation.

The edge is coated with a very thin watery slip layer, brushed on. This charcoal-rich layer helps prevent carbon loss and its increased surface area actually speeds up the cooling for this area.

Yaki-ire – Hardening the Blade

Immediately after yaki-ire, some of the clay has come off at the end of the quench due to blade curvature, and the edge tests successfuly as too hard to cut with a file.

The clay is cleaned off and some of the edge hardness is removed by tempering at a light straw colour.

The blade cleaned and thinned on waterstones, but not quite sharpened, in preparation for wrapping the handle and crafting the scabbard.

Saya – Crafting a Nata Style Scabbard

Two strips of wood glued to a thin piece of wood are planed down until they exactly match the thickness and taper of the spine until about two-thirds or halfway to the tip. A center insert provides stability but leaves open drain holes for adverse weather conditions.

The spine and the edge just contact the wood to prevent rattling or shifting of the blade.

The scabbard is designed so that the blade fits either way in the rectangular opening, allowing for a variety of carries.

The other piece of exterior wood is glued on and clamped to ensure the snugly planed fit is preserved.

The exterior is planed and shaped with a slight taper, lanyard holes drilled, and a kurikata is made but not attached yet.

A scabbard frog is cut and crafted from leather, fit relatively snugly to the top of the saya with a cutout for the kurikata. Another option is to have support from below only but the scabbard would need to be cord wrapped to keep it in place on the draw.

Rivets hold the belt loop to the scabbard loop.

The Nootka Cypress scabbard is oiled with natural tung oil, except where the kurikata will be attached.

The finished scabbard. The frog could also be made with snaps rather than rivets which would make it removable from the kurikata.

Approximately 18 feet of paracord wrapped around the scabbard provides strength and protection to the unit, forms a leg-tie lanyard, and can be removed for emergency use without changing the function of the knife or scabbard.

Island Blacksmith: Hand crafted 309 camp bowie made from reclaimed steel using traditional techniques

Maple Survival Bowie

Another special project, commemorating a survival and life journey milestone for a young friend of the forge. This western style bowie was made with Japanese techniques and has the takedown construction of a Japanese sword, facilitated by a hidden mekugi peg under the paracord shell wrap. The overall look and feel of the knife is reminiscent of the Australian commando knives made c. 1944 for survival and utility use in various environments in the Pacific rim. A maple nata style scabbard with additional emergency-use cord completes the carry.

Island Blacksmith: Hand forged knives reclaimed from files and farm equipment.

The blade began as an old file and was hand forged in a charcoal fire at a demonstration event in 2013, shaped with files, differentially hardened using traditional water quench yaki-ire, and sharpened by hand with natural Japanese water stones.

The hand carved maple handle began as a piece of discarded furniture built in September 1968. The tang and handle are constructed in a similar manner as a Japanese tanto and a single bamboo pin holds the assembly together. The handle is wrapped with flat paracord (core removed) and the lanyard hole is lined with a small copper pipe peened into a tube rivet.

The blade is 5.25″ long and the overall length is just under 10″. The maple nata style scabbard holds the blade in either direction. The scabbard is wrapped with an additional length of paracord which can be used to secure the handle, secure the scabbard to a belt, or removed for use in survival situations.