It took the Colorado School of Mines, Almost every EOS Laser-Sintering 3D printer around the country and I would assume a large truckload of money... But Adam Savage (Myth Busters) built a 3D printed titanium Iron Man suit that can withstand a 45 caliber gunshot on his new show Savage Builds.

It's crazy how far 3D printing has come over the past few years.

https://www.youtube.com/watch?v=_Be_v7uNs4c