Repost from Wired Magazine.

 Big Top at CCA

Big Top at CCA

Alongside collections of everyday objects like light-switch covers and felt bags, Rachel Gant’s SF Design Week offerings earlier this month were decidedly in-season. She was showing a series of bags that convert into picnic blankets, and in the store’s window, she put a giant spinning top on display. It was still light out when the evening event started, and I surely wasn’t the only one eying the combo for a final bit of fun before dusk.

The 20-pound top is Gant’s California College of the Arts thesis project, and its impressive size is by design. Gant wanted the top to take two to operate, one person to hold on to the top itself and another to yank the 15-foot string.

“I wanted it to be an interactive game—something simple and related to materials and space,” she says. It not only needed to be fun, but she wanted it to be something with science baked in. “It’s a play on physics principles,” says Gant. “It’s kind of like what you’d find at the Exploratorium, but for your home.”

Gant started working on the first iteration in March, lathing the top piece of wood herself. But as she experimented, she found that she needed more precision. Part of the problem was just how big she wanted to make the thing. The workmanship matters because an imperfect cut will throw off the spin, and she was new to lathing something so large.

She also decided she needed to kiln-dry the ash wood. The first prototype had warped a bit, which messed with the top’s weight distribution.

So for the next iteration, she made sure the wood was kiln-dried, which made its structure more reliable. Then she took the wood to a local San Francisco craftsman who was able to more easily produce the bigger pieces.

“Typically when you make things, you go through a lot of prototypes,” says Gant. “But with this, you need to make the whole thing before you know if it’s going to work.” But all the design tweaks paid off. Gant’s record-breaking spin—a whopping three minutes and 10 seconds—was achieved on the first try.