The amount of heat is localized to a very small area when melting the powdered metal into a form, build layers are very thin, so really not all that much electrical energy is being used. A small laser sintering machine capable of making metal parts shouldn't take all that much amperage, I'll guess around 50amp peak. Kind of like a medium size TIG welder.
I've been working on getting a decent quality print on this flexible urethane lens cap with the old CZJ logo on it, here's one of the works in progress. I'm also working on one with a portrait of John Brashear emblazoned on the face.