Except for stools without backboards, chairs often have three basic parts: legs, a seat, and a backboard. The more ambiguous the relationship between these three is, the further away the chair is going to be from the fixed concept of a chair. The first thing that came to my mind this time was a cross-sectional shape that looks like an "r" with the legs and back plate continuing. Then, by gathering three of these shapes and supporting the seat surface only with the recessed part of the “r” shape, the three shapes of the legs, the seat surface, and the back plate are vaguely connected, and the load flow looks unclear. I wondered if I could design a chair that is seemingly unstable and not immediately understandable. In addition, by gathering three of the same shape, the part that used to be the backboard can also be used as an armrest, and it creates a shape that gently embraces the person.

When welding aluminum, if the thickness is less than 3mm, distortion problems occur, so even if it is thin, 4mm is often used for my chair design. The shape of this time was open under the front seat, and there was structural anxiety. When I made the drawing for the first time, I set the thickness of the side plate at 5mm for the time being, and was thinking of increasing the thickness while making prototypes. However, after repeated examination of various manufacturing methods, it was found that the initial thickness of 5 mm could be used without any structural problems. Surprisingly, it turned out to be one of the strongest structurally of the aluminum chairs I have designed so far, and I was surprised that it could bear a weight of 100kg without any problems.

Since aluminum is a material that has both softness and hardness (high toughness), it seems that there are still other possibilities for shapes that make the most of its characteristics, and shapes that approach the limits of its characteristics. I will continue to pursue it in the future.


■ Chair
material: aluminum
manufacture: Kikukawa Kogyo Co., Ltd.
design year: 2022.04-2023.02
*This project is supported by Kuwasawa Design School Research grant 2022.