A 13-Year-Old Spent 300 Hours of His Summer 3D-Printing a Mobility Chair for a Little Girl He Had Never Met

For many 13-year-olds, summer is a time for video games, vacations, sports, hanging out with friends, or simply enjoying a break from school.

For Zac Waters, a teenager from Lehi, Utah, the summer of 2026 became something very different.

He spent roughly 300 hours designing, printing, testing, and assembling a customized mobility chair for a 21-month-old girl he had never even met.

What makes the story remarkable is not simply the amount of time he invested. It is the reason he did it.

Zac loved 3D printing. He had discovered the technology through online videos and had become fascinated by the ability to turn digital designs into real objects. But instead of using his hobby only to make interesting gadgets or personal projects, he began looking for a way to use what he knew to help another person.

That search led him to MakeGood, a nonprofit organization that develops open-source, 3D-printable assistive devices for people with disabilities.

Through the organization, Zac was connected with a young child who needed a mobility device.

And then the teenager got to work.

For approximately 300 hours, his summer became a cycle of designing, printing, testing, adjusting, assembling and trying again.

The finished chair was not simply something pulled from a printer and handed over.

It was customized for a real child.

It included features designed to make the device more useful as the girl grew and to better accommodate her needs. Reports about the project describe adjustable supports, footrests, straps, a removable tray, storage space and pink details.

The project transformed what might have been an ordinary hobby into something with a very different purpose: helping a young child move, explore and participate more independently in the world around her.

It Started With a Hobby

Zac's story begins with something familiar to many young people today: curiosity about technology.

He became interested in 3D printing after watching videos about the technology online. At first, 3D printing was simply something he enjoyed learning about and experimenting with.

But hobbies can sometimes become more meaningful when people discover what their skills can do for someone else.

That appears to be what happened with Zac.

Rather than asking only, "What can I make?" he began asking a more important question:

"What can I make that could actually help someone?"

That question led him to MakeGood.

The nonprofit describes itself as a 501(c)(3) organization that designs and fabricates assistive devices for people with disabilities. Its models are made available so that makers with 3D printers can produce useful devices locally. The organization says its catalog includes wheelchair accessories, walker handles, footplates, tray tables and other assistive products.

For Zac, this created an unusual opportunity.

He already had the interest.

He was developing the technical skills.

Now he had a real person to build something for.

The result was a project that would occupy much of his summer.

300 Hours of Work Behind One Mobility Device

Three hundred hours can sound like just a number until you imagine what it actually represents.

It is more than 12 full days if someone worked around the clock.

For a teenager working around normal daily life, it means weeks and weeks of effort.

And the work was not limited to pressing a button on a 3D printer.

A project like this involves multiple stages.

There is design.

There is measurement.

There is material selection.

There is printing.

There is assembly.

There is testing.

There are adjustments.

And then there is the reality that something designed for a growing child cannot simply be treated like a generic object.

The device needs to fit its intended user.

It needs to provide appropriate support.

It needs to be practical for the child and family.

And because it is intended to support mobility, safety and usability matter.

That is one reason the story is more significant than a simple "teen builds something cool" headline.

Zac was applying a technology often associated with toys, prototypes and hobby projects to a problem that affects someone's everyday life.

The approximately 300 hours represented patience as much as technical ability.

Every printed part was another small step toward a finished device.

Every adjustment meant another opportunity to make it work better.

And every test brought him closer to the moment when the project would leave his workspace and become part of someone else's life.