October 4, 2017
How Barber Osgerby Designed the Tip Ton Chair for Vitra
In the new book “Barber Osgerby Projects,” the design firm delves into several of its iconic works, from the Tip Ton Chair to the 2012 London Summer Olympics torch.
The following excerpt is based on a conversation with Rolf Fehlbaum, chairman emeritus of Vitra, and Eckart Maise, Vitra’s chief design officer.
[Barber Osgerby’s] ambition was to create a chair that would respond to the need for movement and allow for dynamic sitting. The criteria also specified that the Tip Ton would be made out of plastic, a sturdy, inexpensive material that could invigorate the school environment with color, while still being recyclable. The chair would also have minimal components, so as to not be affected by vibrations when moved around. Osgerby recalls that, at this point, they did not know, or even care, what the chair would look like: “It was a three-dimensional diagram, a maquette.”
Fehlbaum emphasizes that seating position is a challenge for chair design in general: the sitter needs to be able to lean forward for interaction with the table, or back, for relaxation. Most chairs only support one position. The introduction of the cantilever in the early twentieth century had offered chair designs the possibility of incorporating some movement, but not two distinct seating positions. A great example of this design feature can be seen in Marcel Breuer’s celebrated B64 Chair (1928): instead of having the typical four-leg support, the chair’s tubular-steel front legs are each bent back into an L and joined together at the rear, allowing the seat to flex gently.
Finding a form for the Tip Ton chair that would fulfill Barber and Osgerby’s self-established criteria therefore began with an investigation into the cantilever. Through drawings and full-scale models, the designers explored various types of seats, legs and their interaction with one another. They even made playful mock-ups that combined different parts of well-known chairs produced by vitra.com. In these early experiments, the designers focused on adding movement to the seat of the chair, but the most pivotal development in the design occurred when they moved their attention to the floor. They decided to use skids—horizontal bars that rest on the ground and connect the front and back legs. Of particular significance was the addition of a slightly angled tilt at the front of those skids. A tilt would allow for rocking and movement, but equally support two distinct seating positions: the sitter could either lean back or move easily into a forward leaning, spine-straightening posture. Consequently, the tilt became a defining feature of the chair’s visual identity.
The original idea went through a succession of meetings, tests, and studies, followed by huge numbers of technical drawings, simulations, resin moulds and prototypes. Barber remembers that, at a certain point, they moved the center of balance forward to achieve complete stability. However, the perfect angle for the skids’ tilt (nine degrees) was found through trial and error, a process that involved many mock-ups. When the final form of the chair was decided, “it had character, a personality and a uniqueness.… Every little part of the shape of every little muscle you can see in the chair has a reason,” as Maise later told a journalist. “I think it all makes it memorable.”
This text was excerpted from the new book Barber Osgerby Projects (Phaidon, 2017) by Jana Scholze.
From Metropolis, you may also enjoy “Jasper Morrison on Emeco, Getting Older, and Giving in to Compromise.”