Miyamoto Manufacturing Co., Ltd.
Takashi Miyamoto, President

Magnesium is the lightest among the metals which have been put into practical use in the industrial field. Its specific gravity is 1/4 of iron, and its weight is about 2/3 of aluminum. Taking advantage of this property, there is a global trend toward replacing the parts that conventionally used only iron or aluminum, with magnesium alloys to reduce their weight.

Miyamoto Manufacturing in Koga city, Ibaraki prefecture, is a company which was among the first to notice the potentiality of magnesium, and has continued taking a progressive approach. In 1965, Kinnosuke Miyamoto, who was a father of Takashi Miyamoto, the company’s president and a lathe craftsman, established his own company in Kawaguchi city, Saitama prefecture. Since then, the company has been pursuing the mastery of metal parts machining techniques for more than 40 years.

However, like other parts manufacturers, it was hard to get out of the subcontracting structure under the major manufacturers, and the demands from the clients to lower the price continued every year.

"If I keep cutting the price, it will become almost free. I want to do the type of work in which I can decide the price."

It was 15 years ago when Miyamoto, the company’s president who has been feeling a sense of crisis over the dwindling business situation, came across magnesium. He happened to pick up the material because he had a colleague who was working on polishing magnesium alloys, and Miyamoto was surprised by how light it was.

A magnesium boring bar sleeve which was commercialized in Japan for the first time

Products that use magnesium. All are surprisingly light for metal.

Natural resource is also plentiful

That was how the research and development focused around magnesium was started in the company.

Besides its lightness, magnesium has characteristics such as good vibration/shock absorption and easy to recycle. Supposing that energy of 100% is required to produce a new material, aluminum requires 95% of the energy to recycle, but magnesium requires only 8% of the energy. Because of this, magnesium is said to be an environment-friendly material.

Also it is plentiful in nature, and it can be extracted from a mineral ore called dolomite, or from sea water.

On the other hand, it is hard to handle and this slowed the spread of its use. It is not bendable at normal temperature, thus it needs to be heated to bend. Moreover, the swarf generated during machining is quite flammable, and hydrogen explosion will occur if water is poured while burning. It is a challenge for manufacturers who handle magnesium to control these factors effectively and to process accurately at the same time.

Developed machined parts with a new idea

Miyamoto, the company’s president was thinking about "wishing to make the company’s original magnesium product," and he exhibited a golf putter that used magnesium alloy as its material at the "Small and Medium Enterprise General Exhibition" held in 2003. The putter itself was too light and was not recognized as being practical, but he said he got a new idea here.

"At that time, the material cost was 6,000 yen per kilogram, so it cost 4,800 yen just for the material to make one putter. Thus I was thinking how to improve the cost, rather than the practical use, and I found out that we can get the material with good quality from Taiwan for 1/3 of the price in Japan."

He immediately negotiated with a Taiwanese company, and after reaching an agreement established a subsidiary, Tokyo Magnesium Co., Ltd. in 2004 and started to import raw materials.

At the same time, the company kept improving its magnesium processing technology, and in 2008, achieved the first commercialization of the magnesium boring bar sleeve in Japan. The boring bar sleeve is a cylindrical part that supports the boring bar (blade), which is the cutting tool of the NC lathe. Iron was used until now, but by replacing it with magnesium, the vibration during machining is absorbed and this proved successful in reducing the metal fatigue.

"The conventional way of thinking was to suppress the vibration by using hard materials, but the idea of this new product is to absorb the vibration by using a soft material."

Although it has not been long since its launch, the users commented that "blades last twice as long compared with the conventional products," and it has been received well. The adoption of magnesium boring bar sleeve is steadily spreading.

Magnesium boring bar sleeve installed in an NC lathe machine

A scene inside the factory. Various prototypes using magnesium are repeatedly being fabricated.

Aiming for "Magnesium Ibaraki"

Miyamoto, the company’s president is drawing up a concept to develop the business in cooperation with other related companies within Ibaraki prefecture, rather than carrying out the technological development of magnesium by his company alone. "I thought that if a number of companies form a coalition and share the roles, it can meet various demands that are difficult for one small and medium size company to cope with."

Miyamoto, the company’s president, became the chairman of the "Industry Association of Magnesium in IBARAKI" organized by 41 related companies. He explained, "I would like to establish the brand image so that Ibaraki prefecture becomes associated with magnesium, just as Kawaguchi city in Saitama prefecture, the founding place of the company was renowned as the city of casting."

In Europe, magnesium is already used in 30% of automobile parts. It is the goal of the Industry Association member companies that the Association’s network becomes the recipient when such trend spreads to all kinds of parts.

Along with efforts to enhance the overall value of the company coalition, Miyamoto Manufacturing is aiming at further advancement of technology to produce magnesium boring bar sleeves and its dissemination.

"Although our sales destinations are still limited, I think that there is a significant opportunity as it is said that 230,000 NC lathe machines exist in Japan."

The dream of Miyamoto, the company’s president, is to have one magnesium boring bar sleeve used in every NC lathe machine in Japan.

Miyamoto Manufacturing Co., Ltd. :
Processing/sales of magnesium products

Address: 2393 Mizuumi, Koga-city, Ibaraki prefecture, Japan 306-0215
Phone：+81-280-92-8517
FAX：+81-280-92-8520
Capital: 10 million yen
Employees: 20 persons
http://www.miyamotoss.co.jp