Abstract: A welding torch is supported by a mount which can be oscillated about a vertical pivot that is carried by and movable with an up-down frame which is carried by and movable with a forward-rearward frame that is carried by and movable with a laterally-movable frame. As a result, that welding torch can be oscillated about a pivot which is movable vertically, forwardly and rearwardly and from side to side. A plurality of cams are mounted adjacent each other and act through linkages to provide any desired individual or combined oscillation, up-down, forward-rearward, or lateral movement of that welding torch.

Abstract: A welding machine can form continuous welds of three hundred and sixty degrees on workpieces which are rotated through angles of less than three hundred and sixty degrees by moving the welding torch of that welding machine in one direction circumferentially of those workpieces while those workpieces are being rotated in the opposite direction.

Abstract: A welding machine holds a plurality of metal objects in abutting engagement, moves those abutting metal objects relative to a welding torch, and provides an angular disposition of that welding torch relative to the junction between the abutting portions of those abutting metal objects which foster the formation of a smooth and uniform weld at that junction. The welding torch is mounted on a support which can move as the abutting metal objects are moved relative to the welding torch; and that support can be moved to cause that welding torch to closely "track" the junction between the abutting portions of those abutting metal objects, and also to provide whatever angular disposition of that welding torch relative to that junction which is needed to foster the formation of a smooth and uniform weld at that junction.