A Perfect Fit: The Fractal Vice Chair

Imagine: a wooden chair that comfortably conforms to every contour of your unique buttocks, without pinching it.

We introduce to you the world’s first “fractal” chair — based on a potential application of an expired 1913 patent, invented by Paulin Karl Kunze, for a “fractal vise,” designed for clamping bodies of any shape (try 3D printing your own fractal vise). Canadian maker Eric Tozzi went viral two years ago for restoring the rare antique device on his popular Hand Tool Rescue YouTube channel, attracting over 21.3 million views. It laid the foundation for this 150-pound chair that, to Tozzi’s knowledge, has never previously been made.

“I thought that if you based it somewhat off the drawing, it could be done now using modern techniques,” he tells Make:, explaining he partnered with Fick Tool & Design to create a 3D design mockup, and then outsourced to a fiber laser technology company to cut the metal parts.

The chair has been over two years in the making, with most of the time spent on conceptual planning, and then about one month of “fiddling,” as Tozzi says, with the parts in the evenings after working as a plant scientist at the University of Saskatchewan.

Despite the impressive creations he’s been showcasing on YouTube since 2017, Tozzi clarifies, “I am in no way an expert in chair design, nor an expert machinist or woodworker on any professional level—just incredibly enthusiastic about these types of projects bringing patents back to life.”

That enthusiasm carried him through the biggest challenge: very careful machining of 30 bars supporting the apparatus to ensure functionality. “If they’re off by even a few thousandths of an inch, the actual mechanisms of each fraction will jam and not move at all,” he says. “So, it needs to be incredibly high precision machining, which takes a really long time.”