In particular, you need an actual MIG welder that has a provision to connect external gas. The instructions show a Hobart Handler 140 ... low amperage and duty cycle of the welder mean you need ...
[Integza]’s rocketry projects are one such example, so he decided to explore turning a MIG welder into a 3D printer for his own nefarious purposes. (Video, embedded below.) The build is as ...