This page has a photo of a sprocket from the machine: http://motherboard.vice.com/blog/you-can-now-3d-print-with-metal-at-home http://motherboard.vice.com/blog/

This page has a photo of a sprocket from the machine: http://motherboard.vice.com/blog/you-can-now-3d-print-with-metal-at-home http://motherboard.vice.com/blog/you-can-now-3d-print-with-m... This is a nice first step and all, but there are a number of challenges here. The irregular sparking and popping noises imply that the metal laid down will also be irregular. This uses a regular MIG welder as the print head, and MIG welding only allows you to lay so fine of a bead. Large welds tend to be brittle due to internal stresses, voids, and the like. The more successful commercial metal 3D printers build parts a thin layer at a time. A fine metal powder is sintered on each layer using a laser. This technique is called Direct Metal Laser Sintering (DMLS).