Mason Wilde has always had a passion for figuring out how things work.
When he was 4 years old, he took apart his mother's dining room table and gliding ottoman.
Last year, he built a computer, pretty much from scratch.
But it's what the 16-year-old Louisburg High School junior made about two months ago that has him most excited these days. Not because it was so challenging, but because it's already changing the life of a family friend's 9-year-old son who was born without fingers on one hand, The Kansas City Star reported.
Using a 3-D printer at the Johnson County Library, Wilde made a prosthetic hand that opens and closes and can even hold a pencil.
Just ask young Matthew how he feels about Wilde.
"He's awesome," the boy said, thrusting his mechanical hand high above his head.
The third-grader was born with only a thumb and a few partial digits on his right hand. He can lift stuff with it, balance a book on it, even tie his own shoes. But Matthew said, "I was bored with that. I wanted to do more."
Matthew's condition, referred to as a limb difference, occurs for unknown reasons in about 5 out of every 10,000 births, affecting hands, arms, legs and toes. The condition has attracted unwanted attention to other children, Matthew's mother, Jennifer, knows, which is why she asked that their last name and hometown not be used in this story.
Matthew is adopted. Jennifer was familiar with limb differences when she chose him. Her dad, who died before the adoption, had the same condition on his left hand.
"I remember my dad telling me once that his mother had always wanted him to have fingers," Jennifer said. "And he was self-conscious about his hand well into adulthood. Matthew isn't self-conscious, and I never want him to be."
Jennifer and her three adopted boys moved to Miami County, Kan., two years ago. Children at Matthew's elementary school were curious about the new kid's hand without fingers.
"Every day, kids were asking him, 'What happened to your hand, what happened to your hand,' and I noticed it was wrecking his spirit," Jennifer said. "Social stigma was starting to creep in on him."
Still, Matthew showed no interest in getting a commercial prosthetic hand, his mother said.
What's more, such a hand can cost as much as $18,000. Even with insurance, Jennifer said, "we wouldn't be able to afford that. I'm a single mother."
But when Matthew's mom showed him an online picture of a "Robohand" created on a 3-D printer, he got excited. She knew the Johnson County Library had a 3-D printer that was free for anyone with a library card to use.
"It is so cool," Matthew said, which was just what his mom was hoping for. Maybe the kids at school whose questions seemed to say something was wrong with Matthew would instead ask about his cool robot hand.
The Robohand is driven by the motion of the wrist. Move the wrist up and the hand opens, down and the fingers close.
With it Matthew can write with a pen, but not so legibly just yet. But he is working on it.
"I call it my toy tool," Matthew said. "It — is — the future."
Ivan Owen has heard that sort of sentiment before. Owen co-designed the original 3-D printer Robohand with Richard Van As, a South African woodworker.
"Quite often people born without fingers have learned to manage without, but what I hear quite often from them is that the Robohand is a very exciting new tool for them to use," Owen said in a telephone interview from Bellingham, Wash. "They see it as a cool empowerment."
The idea for the hand started when Van As lost a finger and parts of three others in a workshop accident. He was researching ways to make himself a mechanical finger when he ran across Owen, a theatrical artist who makes large mechanical limbs for puppets.
The two men struck up an online communication to create a finger for Van As. Then a mother in South Africa ran across online postings about their progress and asked them to build a mechanical hand for her son. The two agreed, and the Robohand prototype, made of metal, was born in November 2012.
The first 3-D printer version was made in January 2013, and Van As and Owen put free instructions online.
Jennifer thought maybe she could make the hand for Matthew, but the design was "way too complicated." She thought of Wilde, whom she knew to be a math and computer whiz kid.
It just so happened that Wilde needed a project to occupy some recently realized free time. Playing football, he had experienced his third sports-related concussion. His parents decided, and he agreed, there would be no more of that.
Mason Wilde modified the plans to make a device that would fit the boy's small hand.
"I was already interested in 3-D printers," Wilde said. "I know a little something about them. I wasn't going to pass up the opportunity to use a 3-D printer or to build a prosthetic."
The Johnson County Library keeps its 3-D printer in an area called the Makerspace that opened nearly a year ago.
People have printed Lego-like pieces, small replacement parts for electronics, toys and some 3-D models in the Makerspace, librarian Meredith Nelson said.
"The Robohand is by far the most interesting," she said.
It took about eight hours for the printer to apply polylactide — a thermoplastic derived from corn starch — to form the pieces for the Robohand.
At Jennifer's kitchen table, she, Matthew and Wilde separated each Robohand part from the plastic sheet it was printed into.
With a drill, a pair of pliers and about $60 worth of materials, including a dye kit, screws, nylon string and hard plastic for the gauntlet, Wilde put the hand together. Matthew stood by his side.
"He wanted it to be done as soon as possible," Wilde said.
When Matthew slid his hand into the gauntlet for the first time, he transformed into "the incredible super kid," running around the house giggling and slapping high fives with his brothers and Wilde.
"I was happy, happy, happy," Matthew said, and then jiggled the fingers on his Robohand and wiggled a little hip-action dance, as he put it, "Whopping Gangnam style."
Not only has the hand brought happiness and empowerment to Matthew, he and Wilde have become pretty tight buddies.
Matthew said he wants to always have a Robohand to wear, "but I don't think I will always have the awesome power of Mason on my side, so maybe not."
Not to worry, Wilde said, theirs is a "friendship, mentorship relationship," and he plans to stick around tweaking, tightening and improving Matthew's Robohand so he can continue wearing one as long as he wants.
On top of that, Wilde wants to save for his own 3-D printer so he can make prosthetics for other children.
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