Building two examples of quick and simple sideblast charcoal forges with found and reclaimed materials to demonstrate that lack of equipment and materials should not be a major obstacle.
Ways to improve and expand on these concepts include: mixing copious amounts of chopped straw or charcoal powder (6:2) into the clay to make it refractory, using high temperature kiln bricks, making the walls higher and longer, using the clay to narrow the tuyere to about 1sun/3cm right where it enters at the bottom side of the forge, putting a barrier up to protect the fuigo (and allowing a shorter pipe), allowing the clay to dry before lighting the forge, etc.
Learn more about fuigo, a full traditional swordsmith forge build, or a smaller tanto forge design.
A look at the inside operation of a prototype fuigo (鞴) box bellows…four wooden flap valves (called ben / は弁), two for intake and two for the manifold, control the direction and location of the airflow on each stroke of the piston to provide double action to the single output into the fire.
more about fuigo | making valves | fuigo archives
Sunnobi tanto are larger than ordinary tanto (nagasa above 1 shaku) and may have sori similar to ko-wakizashi. Read more about the process of yaki-ire.
1. Using approximately a 1:1:1 mixture of natural clay, polishing stone powder and ground charcoal to mask the back of a hand forged blade about 1-1.5mm thick to slow down the cooling rate.
2. Brushing on a thin slip layer with extra charcoal added along the exposed edge to speed up the cooling rate and protect from carbon loss.
3. Carefully heating in a charcoal forge supplied by air from a fuigo box bellows until the edge reaches critical temperature.
4. Plunging edge-first into cold rainwater to cool the blade quickly and harden the edge while leaving the rest tough and resilient.
5. Testing for successful hardening with a file and then removing the clay with a mild steel scraper.
6. Slightly reheating the blade over the flames to temper the edge.
7. Test polishing on a coarse Japanese waterstone to check the hamon.
Making a habaki from reclaimed copper. Material is scrap copper from an electrical bus bar, forged and bent to shape, silver brazed with hard silver solder in the charcoal forge with fuigo, finish work done with files and rasps. Watch the shorter overview edit here.
Futokorogatana (懐刀) is translated as “clothing fold sword” and describes a type of tanto mounting meant to be carried in the kimono sleeve or fold. Also known as kaiken, this humble style of hidden mounting is usually unadorned with a smooth profile and lacquer finish. More photos and information.
The fuchi and koiguchi are from a reclaimed buffalo horn souvenir, the kurikata is from a reclaimed horn button, the wrapping is rawhide samegawa, the mekugi is copper and silver. All of the parts are first shaped and fit, then the samegawa is wet formed to the handle contours, dried, and then attached with sokui (rice paste glue). After the scabbard and handle are lacquered, the horn parts will be polished and attached with sokui as well. The mekugi cap is soldered on with hard silver solder in the charcoal forge. carving the inside | carving the outside | final work
In this video the tsuka is carved first, starting with the fuchi end and then the kashira area, carving the profile outlines and then removing the material in between before carving the final shape and sculpting the details. The saya is next, first dimensioning the blank is to approximate size and then profiling the koiguchi and then the kojiri, removing the material and carving as close as possible to the final shape using kanna and kiridashi. Finally any remaining high points in the curves are smoothed with a fine rasp. carving the inside | making the fittings | final work
In this video the tsuka is carved first, starting with the omote side and then the ura, carving each half from the mune to the ha. The saya is next, starting with the omote and then the ura, each half beginning with the fitting of the blade (from the mune towards the ha) and then the fitting of the habaki area (koiguchi). Finally the halves are glued together with rice paste glue, wrapped with leather cord, and wedged tightly to dry overnight. The first half is almost real time, the repeat steps edited out during the second half. The wood is hounoki, carve carefully and check often! carving the outside | making the fittings | final work
A Japanese swordsmith style anvil made from junkyard scrap. The two side pieces are cast steel or iron John Deere 8255C rear counterweights from a shovel dozer. They weigh about 200-240lbs each and measure about 2 1/8″ x 14 3/4″ x 25″. There is a ‘T’ shaped face and stem that extends to the ground between the plates made from welded spring or tool steel and weighs about 70lbs.
The face is about 1 3/8″ x 6″ x 15 1/4″ and has a pritchel hole in it and a sharp edge for cutting on one corner. The combined weight of the plates bolted onto the face and stem should be between 475 and 520lbs. The finished anvil should sit 7-7.5 sun from the ground or from the seat height. See the whole forge building process here.