The invention discloses an arc welding apparatus that imparts a rotational movement to the tip of the consumable electrode to cause molten metal to be thrown by centrifugal force against the sidewall of the slot between metal work pieces being welded. The welding apparatus being configurable to control speed, direction, and/or placement of the electrical arc in relation to the slot. The welding apparatus being configurable to pair with other similar devices and to be cooperatively operated in close proximity and\or on a single weld puddle to accomplish larger and/or complex welds in rapid, repeatable succession.