Island Forge: Part 1 – Foundation

This series of photo essays will document the preparation, construction, and set up of a simple swordsmith style kajiba (鍛冶場, forge building) from the ground up. The main inspiration for aesthetic, form, and technique is the humble Japanese inaka naya (納屋) building style of a century ago.

Foundation

The location for the kajiba slopes down about a foot so a dry stack stone retaining wall was built to level the pad after removing the organic layer of soil. The pit for the smith and the forge was laid out and blocked in and then stones and broken bricks were used to fill around it, along with 3 tons of pit run and then 2 tons of road base. Large flat post foundation stones were set into the road base and leveled.

Large antique sandstone blocks will form the front step (the largest is at least 600 lbs), post foundation stones are set about a foot inside the edges of the level pad.

Floor

As the pad was filled, the Japanese anvil was installed along with an in-floor water bucket and a sunken container for tojiru (clay slurry). A half ton of 1/4″ blue crush with fines was reclaimed from the former workshop floor along with a half ton of reclaimed joint sand help to level the floor. The floor was then brought up to finished height with a combination of natural flagstones and reclaimed fire bricks and red clay bricks.

The blacksmith sits in a central location (bricks at lower left) for all of the necessary work stages at the forge. Clockwise from lower left: clay slurry, in front of the fuigo (not shown), forge base, floor area for straw ash, heavy steel base for wooden straightening stump, anvil, sunken water bucket.

In order to lower the anvil relative to assistants and apprentices acting as sakite (strikers) with large mukozuchi, the smith works from a sitting position at or near floor level. Less than half of the 255lb block anvil (5″x10″x18″) is visible above the floor. The bottom of the pit is the original ground level. The water bucket is flush with the floor to allow the quenching tank to sit over top of it when in use.

The smith is positioned so that everything is within reach and the fuigo, forge, and anvil are located on radiating lines from a central location. Read more about the location and placement of these items in a traditional swordsmithing forge here. A unique addition to this design puts a Western London pattern anvil at the correct height for standing in the pit along with the Japanese swordsmith anvil at the correct height for sitting on or near floor level.

Overview of the workshop floor and pad layout. Various bits of reclaimed clay bricks and natural stones are pieced together to form the floor. Brick laying will have to wait until the ground thaws again.

The next steps will be to prepare and assemble the timber frame.

Timeline

Gathering materials began in Fall 2018, site preparation in December 2018, the lumber was milled in the first week of January 2019, the frame assembled February 5th, and roofed February 7th. Yakisugi siding and tsuchikabe walls installed during March, and interior wall finishing in April. The goal is to have it operational by Summer 2019 minus a few finishing details.

Many of the materials are reclaimed, some gathered from the former backlot and set of Bethlehem Walk in Parksville, Canada. Thanks to all who were involved in one way or another in helping facilitate this project, providing space, time, materials, assistance, advice, and encouragement.