There are more than 3,000 factories in Ota-ku, Tokyo. More than 80% of these companies operate with less than ten employees. The range of products manufactured is extensive, but one feature these products share is the 0.001 mm ultra-precision. These products/parts are essential components for rockets and Shinkansens (bullet train).
With many supporters from around the world, Ota-ku remains the heart of Japanese manufacturing. We interviewed Nakai Seimitsu, an 80-year-old company that represents the craftsmanship and skill of Japanese manufacturing.
Founded in 1937, Nakai Seimitsu specializes in precision machining centered on bearing parts using NC automatic composite lathes. Eighty years since its establishment, Nakai Seimitsu always pursues ultra-precision machining. Machinery and equipment have changed over the years, starting from a potter’s wheel to a cam-type, then automatic lathe, and NC automatic composite lathe. Nakai Seimitsu has been purchasing NC automatic lathe manufactured by Citizen Machinery Co., Ltd. for the past 40 years from Marubeni Techno-Systems. Marubeni Techno-Systems is a distributor of Citizen Machinery. We interviewed Citizen Machinery and Nakai Seimitsu to better understand the role of Marubeni Techno-Systems in the field.