Toyota birch frame Setsuna test car sports Japanese cedar panels
March 4, 2016 | 10:06 pm CST
japanese birch, toyota setsuna
Featuring traditional Japanese okuriari joinery used in beams and lintels, a concept Toyota car will make a first appearance at the Milan Design Week. The Setsuna electric powered model, built like a boat, is intended to become an heirloom and last for generations.  
For the unveiling, Toyota selected a setting - the Milan Design Week in April - where its new car will be surrounded by hundreds of other stylish furniture and cabinetry entries. The electric-powered two seater measures 119 inches long, 58 inches wide, 48 inches tall, with a 67-inch wheelbase. 


Exrteme joinery: wood building skips nails

A cypress building in Japan uses traditional joinery. Its designer hoped to rekindle interest in the techniques.

Toyota says its decision to use wood, "a material that is durable yet prone to change over time," reflects its efforts to give form to the way the carmaker sees the changing relationship between people and their cars.
"The Setsuna symbolizes how cars undergo a gradual transformation over the years, as if absorbing the aspirations, memories, and emotions of multiple generations of a family," says Toyota. It hopes that as a family accrues time and experiences together with this car, caring for it and passing it on to the next generation, that vehicle will acquire a new type of value that only the members of that family can appreciate.
The car's name―Setsuna, meaning "moment" in Japanese―was chosen to reflect that people experience precious, fleeting moments together with their cars. Toyota believes that, over time, these collective moments make their cars irreplaceable to their owners.
To embody this concept, Toyota picked a variety of distinctive types of wood for different parts of the car, including the exterior panels, frame, floor, and seats. The exterior panels of the car were developed jointly with Sumitomo Forestry Co., Ltd. (It's holdings in North America include Canyon Creek Cabinet Company, acquired in 2011.)
Wood provides uniquely appealing characteristics that are not offered in conventional cars: it can last for many generations if properly taken care of and it also changes in coloration and texture in response to its environment (particularly temperature and humidity) and conditions of use, taking on a unique character and depth.
"We evaluated various ways to express the concept and selected different lumber materials for specific applications, such as Japanese cedar for the exterior panels and Japanese birch for the frame," said Kenji Tsuji, the Toyota engineer overseeing development of the Setsuna, in describing his design process. "We also paid particular attention to the sizes and arrangements of individual parts."
For the assembly structure, Toyota adopted a traditional Japanese joinery technique, okuriari, which does not use any nails or screws.
"The completed body line of the Setsuna expresses a beautiful curve reminiscent of a boat," says Tsuji. "We would also like the viewer to imagine how the Setsuna will gradually develop a complex and unique character over the years. The car includes a 100-year meter that will keep time over generations, and seats that combine functional beauty with the gentle hue of the wood."

Have something to say? Share your thoughts with us in the comments below.