Ohzen is a manufacturer of machining processes for cast iron, stainless steel and specialty metals. The metal parts that it manufactures are widely used in ultra-high precision devices such as Japanese-made three-dimensional measurement equipment and the electron microscopes used in brain surgery.
It is also involved in the machining of difficult-to-cut materials and specialty metals like titanium and magnesium. The clutch levers and steps that it cuts from titanium for use in American-made motorcycles were originally made just for the company’s own use, but their remarkable quality has earned them the rabid devotion of fans. This skill in high-precision metal cutting has made itself known in a wide variety of fields, ranging from precision machine components to custom parts that earn raves from motorcycle enthusiasts.

Machined Parts for Ultra-High Precision Equipment: The skill of expert craftsmen shines through

Ohzen’s factory is in Nagaoka, Niigata prefecture. Niigata is one of the snowiest places in the world, receiving several yards of snow every winter. Snowy Niigata has earned a reputation throughout Japan as a center of manufacturing, especially metalworking. Ohzen was founded in 1973. Since then, it has continuously been involved in the manufacture of machine parts through metal cutting. A core of its business is parts for precision positioning tables. Precision positioning tables are used in fiber optic and other testing of precision equipment; they are made up of a precision table that is mounted on a linear guide rail so that it slides smoothly in a straight line. High precision (on the level of hundredths of a millimeter) is vital when cutting parts for these products. They are usually made of stainless steel, cast iron or aluminum, and while titanium and magnesium are hard to process, they are also used due to their light weight. These parts are created by first cutting the material to a precision of a hundredth of a millimeter, and then finishing them by polishing to a precision of a thousandth of a millimeter (1 micron). This process of high-precision cutting and polishing demands the experience and intuition of an expert craftsman. Even at Ohzen, there are some processes that only a few select employees are allowed to be involved in. They are able to cut linear guide rails in a single process, whether their length is just a few inches or as long as 2 yards. These rails are often made of stainless steel, which is difficult to work because thermal expansion causes it to bend. However, the skill that the company has built up over a history of more than 40 years enables their craftsmen to manufacture warp-free rails with high precision by repeatedly cutting them one side at a time. Takenori Ohmiya, the director of its production department, is confident in the in the company’s technical abilities, saying that “We brag that the parts we make for things like Japanese-made three-dimensional measurement equipment and electron microscopes have ultra-high precision at the level of thousandths of a millimeter, and you need that kind of processing skill to make them. The fact that these parts are made by experienced craftsmen might be why they are chosen for that kind of precision equipment.”

 

Looking Towards the Future of Titanium and Magnesium

Ohzen is also actively engaged in the processing of difficult-to-cut materials like titanium and magnesium. Titanium is a material that is known for being strong and lightweight, but also for being hard and difficult to cut. Ohzen also processes long precision tables made of titanium, and its ability to cut and grind them with the same high precision as products made of other metals is one of its great strengths. This kind of skillful processing has gotten Ohzen attention from motorcycle fans as well as the equipment manufacturers who have made up its customer base in the past. It used its skill in cutting titanium to make clutch levers and steps for American-made motorcycles as an internal project. It was a challenge intended to increase the skills of its younger craftsmen, with the goal of emphasizing how replacing ordinary stainless steel clutch levers and steps with titanium parts made the body lighter and changed its feel. It was just meant to be an independent project and there was no plan to sell the parts. But they came out with such unexpectedly good quality that they caught the eye of motorcycle fans and the company’s American partners, and it began making unique custom parts to order. It has also taken advantage of technical guidance from outside experts to develop its ability to process magnesium, which is dangerous to work with due to the flammability of its swarf. It is now able to carry out high- precision magnesium work like cutting and mesh processing. Ohmiya says that the company is putting its efforts into “further perfecting our skills, because we expect that the demand for titanium and magnesium will grow in products like aircraft and the appliance housings where light weight is vital.”

Ohzen is able to handle large and heavy pieces like bases for manufacturing equipment, as it can process components as large as 1500 mm X 2000 mm. Most machining companies specialize in either large or small products, but Ohzen’s ability to manufacture parts of all sizes, from the smallest to the largest, is

a great advantage for the manufacturers who order from them. Furthermore, Ohzen’s parent company is a major tool manufacturer that produces products like carbide drills. Getting feedback regarding the use conditions for tools from the real-world use of its products is a key part of its top-notch technical abilities and fast customer service. Additionally, our partnership with a university fracture engineering laboratory makes it possible to back up the technical expertise of its experienced craftsmen with measurements, endurance testing and other kinds of objective data, further improving the quality of its work. It has also created the “Nagaoka cluster,” which brings together local vendors in fields like cutting, assembly and heat treatment to create an organization that provides the mutual advice needed to handle special projects and short delivery schedules. Ohzen has English-speaking employees on-site at all times, so it can communicate with overseas manufacturers by email or phone. As Ohmiya says, “We are starting to actively seek out orders from overseas. We are also looking forward to working with fabless companies and companies in other industries. We’re eager to help you find solutions for any type of metals or special or precision processing, and we look forward to talking with you.”

Ohzen Co. Ltd.

Business Description: Ultra-High Precision Machining
Headquarters Address:1040 Tokamachi Nagaoka-City, Niigata
Representative director Isoo Omiya
Founded: 1973
Number of employees: 22
Website: www.ohzen.jp