Whenever the question of metal 3D printers comes up, someone always chimes in that a MIG welder connected to a normal 3D printer would work great. A bit of research would tell this person that’s already been done, but some confirmation and replication is nice. A few students at TU Delft University strapped a welder to a normal, off-the-shelf 3D printer and made a few simple shapes.
This project builds on the work of [Joshua Pearce] et al. at Michigan Tech where an MIG welder and delta bot was used to lay down rather complex shapes on a metal plate substrate. The team at TU Delft used a cartesian bot – a Prusa i3 – for their replication because of the sheer mass of moving a metal build plate, firebricks, and welder around.
In the first few prints on their machine, the team was able to lay down enough metal to build a vertical wall. It’s not much, and to turn this into a finished part would require some machining, but these are only the beginning steps of what could become a legitimate way of creating metal parts. Video below.
For years now, people have been trying to develop an affordable, RepRap-derived 3D printer that will create objects in metal. There has been a lot of work with crazy devices like high-powered lasers, and electron beams, but so far no one has yet developed a machine that can print metal objects easily, cheaply and safely. For The Hackaday Prize, 
The project featured in this post is an entry in 
If you think about it, the RepRaps and other commercial 3D printers we have today are nothing like the printers that will be found in the workshops of the future. They’re more expensive than they need to be, and despite the RepRap project being around for a few years now, no one has cracked the nut of closed loop control yet. [mad hephaestus], [Alex], and [Will] over on the Hackaday Projects site are working on the future of 3D printing 
