Abstract: A system and method of creating molten metal droplets is disclosed. The system may be used for 3D printing. The system relies on a change in momentum of the droplet relative to the tip of the metal microwire to cause the droplet to separate from the tip of the metal microwire. The change in momentum can be created by using an oscillating printhead. In other embodiments, a mass strikes the printhead to cause the droplet to separate from the metal microwire. The metal microwire may be heated using a heat source, such as a laser, an induction coil or a plasma arc.