The best kind of wood for sashimono is the Japanese big-leaf magnolia (hoonoki), which is supple and easy to process, and which readily takes the application of urushi. The wood piece is cut to the appropriate length and thickness matching the size of the bowl, tray, etc. to be produced.

Both ends of the piece are scraped down thinly using a rounded saw, giving them the same thickness when bent into a ring shape and matched up with each other.

The initial wooden piece is immersed in boiling water. When it has reached the desired softness, the wood is removed from the hot water and wrapped or curled around a special log called the koro, which the artisan rolls slowly to bend the wood into the desired shape. The ring-like form must be achieved before the wood dries out completely, at which point a wooden wedge is attached to keep the shape in place. The rounded piece becomes the side element of the final lacquerware piece.

After three days or so of drying, the curvature is set permanently. Once the piece is completely dry, the wooden wedge is removed and adhesive applied, with uneven areas “broken in.”

The piece of wood that will serve as the bottom of the eventual lacquerware item is cut so as to slip precisely inside the frame created by the sides, and is then affixed to the frame with an adhesive.

The edge pieces are beveled and molded to facilitate the subsequent smoother application of urushi in the next step of the production process. Additionally, the surface is polished down to a smooth finish.