The first key to thinking about 3-D printers is this: Do not think printer. Think magic box that creates any object you can imagine.
In the box, razor-thin layers of powdered material (acrylic, nylon, silver, whatever) pile one on top of the other, and then, voila — you’ve got a shoe, or a cup, or a ring, or an iPhone case.
It’s miraculous to see. Press a button, make anything you want. But just how important is 3-D printing? Unlike earlier big-deal technologies (like, say, the tractor) 3-D printing won’t really replace what came before.
“If you’re producing trash cans or stadium seats, you’ll more than likely produce them the old way,” says analyst Terry Wohlers.
And for consumers, the economist Tyler Cowen points out, it’s still way easier to order something from Amazon than print it yourself — and that’s how people will buy things for the foreseeable future. Still, 3-D printing is amazingly powerful for personalized applications.