Sakai cutlery Photo:Osaka Prefecture

Sakai cutlery Sakai uchihamono

High quality products and traditional techniques
made by first-class artisans

Description

What is Sakai cutlery ?

Sakai traditional blades are hammer-forged knives produced in the cities of Osaka and Sakai, Osaka prefecture. To achieve both strength and cutting quality, this craft is made by combining soft iron and steel.
This craft is forged to have a sharp keen-edged blade. In recent years, the production of kitchen knives stamped out from a steel plate with a sharpened edge section has increased. In contrast, Sakai traditional blades are made by hammering two different types of metal, soft iron and steel, and finishing to a final blade shape. Knives forged in this traditional way have excellent solidity and a long lasting sharpness.
The production of the knives can be broadly divided into three distinct production processes: blacksmithing, sharpening, and attaching the handle. To maintain the highest quality, the work is distributed between these three stages. There is a broad range of knife shapes and sizes according to intended purpose. It is said that more than 90% of knives used by chefs in Japan are Sakai traditional blades.

History

In and around the city of Sakai, there is a large number of ancient tumuli or burial mounds including the Daisen Kofun, a large key-hole shaped mausoleum of Emperor Nintoku, believed to have been constructed in the Kofun (Tumulus) period (300-538). Considerable amounts of spades, hoes, and tools were manufactured to enable such massive engineering works of burial mounds. The blacksmiths who produced the tools established a settlement in Sakai and continued cultivating their craft to make tools and swords.
In 1543, the Portuguese brought guns and tobacco to Japan. Sakai, with its trained metal workers, became a major center for the manufacture of firearms, especially toward the end of the Sengoku period (1467-1568), a time of social upheaval and near-constant military conflict. With the start of the comparatively stable Edo period (1603-1868), the demand for firearms decreased, but smoking became popular, creating a demand for tobacco leaf cutting knives. The tobacco knives made by the craftsmen of Sakai were of high quality and considered better than imported knives. The quality of these knives led the Tokugawa shogunate (feudal military government) to stamp them with the Sakai Kiwame mark and create a government monopoly. The excellent reputation of the Sakai traditional blades soon spread throughout Japan.
Later with the mechanization of tobacco production, the demand for tobacco knives dropped, but craftsmen shifted to the production of cooking knives and gained lots of support from professional chefs.

General Production Process

  1. 1. Steel welding Steel coated with boric acid, borax, and iron oxide powder is stacked upon red heated soft iron and softened in a furnace at about 900ºC (about 1652℉). The two metals are hammered to bond and create a steel and iron plate for the base of a blade.
  2. 2. Shaping The flattened iron is reheated to about 600 to 700ºC (about 1112 to 1292℉) and hammered out repeatedly to thin the metal. The iron and steel are fused and the rough shape of the knife is created. Any excess metal is cut off and the tang (attachment) for the handle is also cut to its required shape.
  3. 3. Cooling down The shaped knife is set down on a bed of straw and left to naturally cool down. The slow cooling of the knife leading the straw to become ash helps remove internal distortions.
  4. 4. Rough hammering To flatten out hammer marks and tiny holes left from shaping, the room temperature blade is hammered. Rough hammering beats out impurities, tempers the blade, fixes any distortion, and creates a uniform thickness.
  5. 5. Cutting The knife is placed on a cutting template and all excess metal is cut off.
  6. 6. Grinding After fixing distortions, an engraving is made on the reverse side. Excess metal and rough edges caused by cutting are smoothed off, and the entire surface is refined with a grinder. The knife is also hammered to revise any distortion.
  7. 7. Mud coating The knife is coated with mud to prevent uneven heating and ensure quick and even cooling during tempering. First, any oil or remaining dirt is removed from the knife, then mud is applied, and the blade is left to dry near a furnace.
  8. 8. Tempering Rapid cooling changes the molecular constituency of metal by making it harder. The process is very basic as the knife is heated to 750 to 800ºC (about 1382 to 1472℉) and immediately plunged into cold water. The knife is heated again to 180 to 200ºC (about 356 to 392℉) and allowed to cool naturally which increases the blade's viscosity and strength and helps prevent chipping. To judge the right temperature and know when to stop heating, water is splashed onto the blade and the way the droplets run is watched by the craftsmen, who rely on training and experience.
  9. 9. Polishing Polishing turns good steel from a simple metal sheet into a knife. This process occurs in the following order of rough polishing, fine polishing, reverse side polishing, hazing, and then final polishing.
    Although named \"rough\", the rough polishing is an important process as it determines the angle of the blade edge. During this step, any visible distortion is diligently checked. Next, for fine polishing, the blade edge continues to be worked and any scratches and distortions resulting from rough polishing are polished, along with the adjustment of the blade thickness. In this stage as well, any distortion is checked. For reverse side polishing, the reverse of the blade is also lightly polished. By increasingly finer polishing, scratches are removed and any distortion is checked. During hazing, kneaded whetstone powder is rubbed on the knife blade, giving the iron a flat subdued color and shining the steel. This clear border between the iron and steel helps show off the beauty of the knife. The final polishing consists of a very fine whetstone used to carefully polish and finish the blade. With a razor edge of the highest quality, the blade is ready to be fitted with a handle.

Where to Buy & More Information

Sakai Traditional Crafts Museum

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