3D printing has come a very long way in the past decade, particularly in the consumer market. But all consumer 3D printers produce plastic parts and metal 3D printing is out of the reach of hobbyists. Today's metal 3D printers utilize the SLS (Selective Laser Sintering) process, in which a laser melts and fuses metallic powder. But SLS 3D printers are very expensive — often hundreds of thousands of dollars. If we're lucky, more affordable options will hit the market in the future. In the mean time, YouTuber Integza, AKA Joel, is experimenting with metal 3D printing with a welder.
MIG (Metal Inert Gas) welding works by feeding metal wire from a gun onto the work piece. When the wire makes contact, it completes an electrical circuit that instantly produces enough heat to melt both the wire and the work piece. At the same time, the gun's nozzle ejects a gas mixture to shield the molten metal. The result is a clean, strong weld. Because the gun feeds wire into the weld, it adds material. Joel figured that he could take advantage of that fact to build up material over time in the same way as a typical 3D printer. This isn't a new idea, but past results from other tinkerers have been lackluster and expensive. Joel wanted to see if he could get good results without spending a lot of money.
The two primary parts of this build are an Elegoo Neptune 2 FDM (Fused Deposition Modeling) 3D printer and a cheap Nutool RSN120FWS MIG welder. Joel started by removing the Neptune's original extruder and hot end, as well as the aluminum print bed. He replaced the bed with a sheet of steel and attached the welder's gone to the extruder carriage with a 3D-printed mount. The latter melted immediately in Joel's first test, because it was being cooled by the fan. Joel then replaced the mount with a redesigned version that keeps the gun at an angle relative to the steel workpiece and ensured that the fan was running. The results after those modifications were better, but still far from usable. Ultimately, Joel's experiments ended in failure. Even so, they are worth watching and learning from. Maybe you can learn from Joel's lessons and finally bring metal 3D printing to the hobbyist market.