A method and apparatus of forming a root bead in a gap between spaced ends
of at least one workpiece. The gap includes an open root. A metal cored
electrode having a metal sheath and core materials is used to for the
root bead in the open root. The core materials include little or no flux
agents. The metal cored electrode is advanced at a given wire feed rate
toward the open root to weld the ends together by at least partially
filling the open root in a first weld pass. A welding current having a
controlled waveform is used. The waveform includes a succession of
welding cycles each having a short circuit portion and a metal the metal
cored electrode and to cause the metal cored electrode to melt and
transfer to the ends in the open root to form a root bead. The formed
root bead has little or no slag on the upper surface of the root bead. A
shielding gas is used to at least partially protect the molten metal in
the open root from the atmosphere.