Shinshu forged blades

The geography of Shinshu uchihamono is precise: Nagano City, Chikuma City, Shinano Town, and Iizuna Town form the main production area. Furuma in Shinano Town is also connected with the craft, and the cooperative is based in Tominou, Shinano Town. When the Shinshu sickle is placed along the Hokkokukaido in northern Nagano, the scene becomes concrete: old road, village, smithing workshop, thin single-bevel grass-cutting sickle, and a hand pulling a wooden handle through grass.

Shinshu uchihamono covers several working blades. Sickles belong to grass cutting, kitchen knives to food preparation, and nata hatchets to heavier tasks; within the same local craft family, iron, carbon steel, and wooden handles are shaped for different jobs. The work associated with Mitsuyoshi Hatayama includes sickles, nata hatchets, vegetable knives, deba knives, and bonsai tools made to order, showing how a maker adjusts the blade to the use in front of it.

The Shinshu sickle depends on shibazuke and tsuri. Shibazuke gives an angle between the blade and the komi, the part fitted into the wooden handle; tsuri works with the posture of the sickle and the feel of the cut. Because cut grass gathers toward the hand, the blade angle is part of the tool’s movement in the field. In the early 19th century, sickle makers are said to have developed shibazuke and tsuri, while another maker improved a double-bevel sickle into a thin single-bevel blade; those forms are treated as models for the present Shinshu sickle.

The sickle process begins with base iron and steel. After preparing both materials, the maker forge-welds steel onto the base iron; one described example joins two millimeters of steel to nine millimeters of base iron. Blade steel is heated in a furnace, stretched and widened by hammering, the komi is bent, the body is opened out, and the cutting edge is trimmed to size. Iron supports the body, carbon steel forms the edge, and the two roles settle into one thin tool.

After shaping, the sickle passes through rough polishing, stamping, smoothing, and intermediate grinding; during smoothing, tsuri and shibazuke are added. For quenching, the blade is coated with clay, held at about 780 degrees Celsius, and rapidly cooled in water. Sharpening, grinding, and finishing are done by hand, and the wooden handle becomes the point where hand force meets the blade. The 17-step workflow gives order to edge, angle, thickness, and handle position.

Mitsuyoshi Hatayama’s explanation shows how intended use enters the choice of steel. Lower-carbon steel suits thick sickles and planes, while higher-carbon steel suits thin sickles and kitchen knives; changing sickles according to the kind of grass also changes workability. After completion, the maker uses the blade himself to check its cutting quality. The craft continues through concrete decisions: what the blade will cut, how thick it should be, which steel fits, and how the edge should be sharpened.

The Shinshu Uchihamono Industrial Cooperative connects craftspeople and wholesalers. Its organizational history begins with the Furuma Village Sickle Industrial Cooperative in 1951 and reaches the current cooperative name in 1981; it is based in Tominou, Shinano Town, and has 10 members. A smithing experience tour began in 1983, and school social-study experiences began in 1988, giving the sound of hammering and the shape of blades a place in local learning.