Can 3D Printers be used to print PCBs?

Oh for a 3D printer, and the time to experiment with it !

I'd have the parts clipped into a 3D printed plastic frame

That might be the way to go, have each component sunken into the plastic layer, with just its legs standing proud, bare parallel wires connecting them, and an insulating layer before the next lot of wires crossing the first ? ........