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) style of a century ago.
Earthen Walls
The interior walls are arakabe (荒壁), a traditional infill technique used extensively in Japan, and some of the lower sections are reclaimed wood. Arakabetsuchi (荒壁土) is a rough mixture of natural clay, sand, and straw applied over lath (komai/kabekomai 壁小舞).
In this case the soil was used as-found and large rocks were picked out during mixing and application. In the Kansai region (eg. Kyoto and Osaka) the mixture is sifted through a 50mm screen for consistency. For a less-utilitarian structure the arakabe would be coated with a sandy middle layer and a finer top layer of finely screened material.









Cedar Blackout Panels
In order to facilitate light control during operations such as yaki-ire, two hanging panels made from reclaimed boards can be hung in various locations in the forge. They are sized to completely block the north windows but can be used to partially block the larger windows and even the smoke louvers if necessary at certain times of day.

Split Cedar Shutters
Light control on the south windows is facilitated by exterior shutters that swing upwards (shitomibame 蔀羽目) to create shade even when opened. The material is thin boards of split cedar and they can be propped open at various angles or hung from hooks above like shitomido (蔀戸).






Timber Workbench
A sturdy mounting spot for the leg vise and a surface for tools. The raw materials are salvaged posts and hand sawn first slabs. A shelf below will provide much needed storage space off the floor.


The next steps will be to organize the tools and steel and start forging!
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.
Thanks to all who were involved in one way or another in helping facilitate this project, providing space, time, materials, assistance, advice, and encouragement.