Ok guys, I've worked with what has become known as 3D Printing for years, like from the mid 80's. It was then known as Stereo Lithography and yes, the process has come a LOOOONGG way since then. Originally we could only make small parts that were more for "look-see" rather than actual working parts. I still made prototype air cleaner and related parts by vacuum forming right up till about 10 years ago when usable "3D printed" parts were becoming available and at cheaper pricing. I could still cut a weld most of these pieces when quick changes were needed. What really got interesting was we could now "print" a complete air induction manifold that usually only needed minor touch up to be fully functional. Before it entailed building a temporary injection mold costing many tens of thousands of dollars. Even then those "printed" manifolds would cost anywhere around 10 grand a piece. These were made from a Nylon based material and were very strong and withstood all the testing required to verify for production.
Yes it's a great tool, but it is NOT in my opinion a replacement for injection molded parts good enough for our cars. Problem is, these "printed" parts are built up in layers. The thinner the layer, the better the quality, but that brings a higher price tag as it take way longer to "print". As I said, this technique has come a long way in the last 10 years and will continue to evolve and someday it may make very satisfactory parts, but not yet.
Geoff.