Next Year's 3-D Printers Promise Big Things — Really Big Things: 2012 has been a big year for 3-D printing, but the industry has quietly been growing for decades. And the innovations are impressive ? for every new plywood-clad 3-D printer kit that makes the rounds on the internet, engineers are developing ways to print titanium parts for jet engines that will change the aerospace industry. This week at Euromold, a manufacturing trade show, the companies behind these devices are demonstrating new products and highlighting the novel technologies that will change the way we build things.