Vol.7  Takeyuki Kaedeoka

April 18, 2009 2:35 AM update

"Spring is machinery parts storing elastic energy with using elastic restoring force of elastic body including metal. Mass production in China and Japan is a mainstay, but there are still some venders existing that make it by hand in a small-scale production. Kaedeoka Spring Industrial Co., Ltd with a history of 50 years in Sumida-ku, Tokyo is one of them. The former master who used to be a fertilizer and manure wholesaler started the factory making springs in the postwar period. Now the second-generation, Takeyuki Kaedeoka has inherited the skill.
" When I began to understand things, my house was already as a spring factory where some craftsmen were working, so I wondered if I would do such work when I grew up, with my child's mind. When I entered a high school, my father farced me to go to the industrial high school(LOL). But I am a flesh and blood from my father, so I've always loved manufacturing. I was going to think that it was better for me to study more, and then studied in a machine engineering school after the high school. That's why I had been about 20 years old when I firmly started to work in the factory." Mr. Kaedeoka radiantly talks with holding the spring of his own making in his hand.

The 90% of whole spring production has to depend on machine. Springs are mostly wound to some degree for shape forming and are fine adjusted by the craftsmen. Even though it is accurate on the drawing, the finished spring has to have some margin of error. The craftsman's work is to adjust such error. 'Load accuracy value' is to indicate how long spring stretch up to when it is applied with definite strength. A proficient skill is required to adjust this value adequately. The craftsmen use the old-style machine called 'foot press machine' to open some space between the springs and adjust the load accuracy value, then, heat-treat to fix the spring form. Because the spring is of metal, it cannot be heat treated many times. Therefore, the load accuracy value should be completely adjusted by just 1 or 2 times of heat-treating.

"The highest quality springs should be made by hand. Such order is actually rate, but in case that we need to adjust the load accuracy value with an uncertainty of 1%, it should be certainly by hand. As for rockets, they need the springs of the high accuracy, right? I assume that a certain spring manufacture must make one by one with minutest care. Yah, sure, I also believe that the one of the reason why the small factory is chosen is to make the highest quality products."

What such 'Kaedeoka Spring factory' has been working for over 10 years is the household goods used existing skill for their spring production. The trigger is that the designer looked at the spring which Mr. Kaedeoka was using instead of a key ring suggested its merchandising. The unique design and the handcrafted high quality piece by piece attracted interest in the market, and the items designed and produced by 'Kaedeoka Spring Industry' are now being sold in the design store of 'MoMA', the Museum of Modern Art, New York.

" MoMA's staffs say that producing the goods abroad can save cost but they are inferior in quality. Actually, there are several goods that only the licenses of the designs are owned by us but the productions are done in China. But when we receive such offers, we state our conditions that we inspect the goods before introducing them to the market, because we cannot use our name for the goods that are low-quality. The springs made abroad has now been steadily coming into Japan. Such springs are made by the machines from Japan, so the quality level of springs has been also improved in Korea and China. However, the Japanese skill has still been better."

"Since I started to make the springs of household goods, I began to forget how old I was." Mr. Kaedeoka says with a smile. He reached his 65th birthday last year, but he still has a long way to retire as long as he keeps such mind.

Kaedeoka Spring Industrial Co.,Ltd
Address: 5-9-5 Tachibana Sumida-ku, Tokyo, Japan
Tel: +81-3-3618-6812

In case of making each product by hand, it is difficult that the spring side is perpendicular to the spring bottom. Therefore, the delicate works including measuring the angle and trimming some parts are necessary.
'SPRING CLOCK' is an item from the collaboration between the designer, Mr. Mizue Fujimatsu and Kaedeoka Spring Industry.

'CARD HOLDER' made of the steel coiled tightly is available at 'MoMA',too. It would be suitable for organizing things including name cards and letters.
'Foot press machine' for adjusting the load accuracy value: the craftsmen step the pedal, and insert the end of machine between the springs to adjust space of the springs.
There are a row of different pincers on the shelf for different uses. That's amazing that the quantity is nearly 100 types.