Marbles, Metal, and Physics Magic

Different colored marbles
All photos courtesy of Tom Harold

Tom Harold, BA’94, was both delighted and positively transfixed.

“It was George Rhoads’s rolling ball sculpture in the [Indianapolis] Children’s Museum,” he recalls. The kinetic piece, Science in Recess, featured motorized tracks, swooping billiard balls, and clanging gongs—and it inspired Harold to ditch his day job to pursue an outright obsession. How were these sculptures made? How did they work? And, most importantly: How could he make his own?

Tom Harold poses next to rolling-ball sculpture
“With some of the tracks I have a general idea of where I want them to go, but after a while the sculpture kind of dictates where it’s going anyway,” says Tom Harold.

“When I started, I had to find authorities on the subject,” Harold says. “There were no how-to books or videos. I had to cast far afield to find these things.” Leaning on his journalism chops, he interviewed kinetic sculptors and took classes in metal arts and welding. He even worked as a shop welder.

Today, Harold is a full-time metal artist, selling his original rolling-ball sculptures worldwide for up to $10,000 for large installations or a few hundred dollars each for desktop-sized pieces. With their loops, jumps, teeter-totters, and the occasional motor to lift and drop marbles along hand-bent, arc-welded bits of stainless steel track, Harold’s creations can take several months to complete.

While he was originally influenced by George Rhoads—the “godfather of rolling-ball sculpture,” Harold maintains—he points to another George, who helped him get the ball rolling, so to speak. “George Rickey (DFA’74) is a very significant kinetic artist who attended and taught at IU many years ago,” he adds.

Like the kinetic giants he admires, Harold dreams big. His larger works reside in the Philadelphia Children’s Hospital and the Indianapolis Public Library. “At the Central Library, they’ve told me, ‘We have kids who come in every Sunday [just] to see it,’” Harold says. “‘It really fascinates people. It really gets their minds going.’ That’s just what [originally] happened to me!”

Tomfoolery rolling-ball sculpture
Tomfoolery, a rolling-ball sculpture, was created especially for the Indianapolis Public Library Central Branch. “I’d been wanting to do a sculpture involving dedicated toned instruments for some time and already had a xylophone, waiting for the occasion,” Harold says.

Someday, Harold hopes to go bigger still. “With a really large space, you can do things that you can’t in small spaces, just [due to] physics being what they are,” he explains.

This article was originally published in the Summer/Fall 2021 issue of the IU Alumni Magazine, a magazine for members of the IU Alumni Association. To view the current and past issues of the IUAM, visit

Written By
Susan M. Brackney
Susan M. Brackney, BA’94, has been a professional writer since 1995. A member of the American Society of Journalists and Authors, she has written four nonfiction books, including Plan Bee: Everything You Ever Wanted to Know About the Hardest-Working Creatures on the Planet.