Boy gets prosthetic hand made by 3-D printer - Subtitled.

Two years ago, Paul McCarthy began searching for an inexpensive yet functional prosthetic hand for his son Leon, who was born without fingers on one of his hands. McCarthy came across a video online with detailed instruction on how to use a 3-D printer to make a prosthetic hand for his son. Michelle Miller reports.

Walt Disney once said that animation can explain whatever the mind of man can conceive.

He was talking about cartoons but advances in technology have taken

that basic concept to a whole new dimension.

Michelle Miller shows us how the idea of a modern day inventor became a 3D reality.

Grabbing a backpack is hardly the feat of a superhero

unless you're 12-year-old Leon McCarthy

and you're hand looks like it's straight out of a science fiction movie!

Michelle: You've actually become sort of a ...

Leon: Cyborg!

Michelle: There's a cool factor

Leon: Yeah, it's special instead of different.

Leon has been special since birth.

When he was still in the womb, restricted blood flow prevented his hand from developing.

I saw his hand sticking up and there were no fingers on it.

And it was hard for my wife, it was hard for me.

Two years ago, his father, Paul, began the search for an inexpensive, functional prosthetic

What he found was this internet video posted by Ivan Owen, an inventor in Washington State.

I've always had this vision of people being able to build their own prosthetic device at home.

Owen, and a collaborator in South Africa, designed a hand that could be

made by a 3-dimensional printer.

It's essentially like a hot glue gun. It's plastic that feeds into it,

the printer head gets really hot, it liquifies that plastic and then, layer by layer

it creates an object.

The design relies on wrist movement. Downward motion creates cable tension that

closes the fingers while a move upward opens them.

The assembly instructions were posted for free on the internet so someone like

Paul McCarthy in Marblehead, Massachusetts could print it.

He took the idea to his son.

Leon: I thought he was a little crazy.

He was like "We can print all these fingers and then like, clip them all in"

and it was a little too much.

Michelle: The first time you saw it, and when you tried it out

Leon: It was pretty awesome, yeah.

Michelle: What made it awesome?

Leon: I could pick up, say like, a water bottle, like say, I could pick up my pencil.

Michelle: What is it like to see him with this?

Making your kids happy is like the most rewarding thing you can have as a Dad, right?

The price tag was also appealing.

Mini 3D printers sell for about $2000, materials are far less expensive.

This thing cost us like 5-bucks, 10-bucks, you know, whatever, it was nothing.

What would a prosthesis cost you?

$20,000 ... $30,000.

The cost allows father and son to experiment with newer designs.

Leon: When I outgrow a hand we can easily make a new one.

It's a do-it-yourself solution that was unthinkable before technology made ideas printable!

That's cool ... ... Yeah.

Michelle Miller, CBS News, Marblehead, Massachusetts.