Abstract: A method and apparatus for welding a tube to a tube plate such as in a vehicular radiator core are provided wherein a tube end formed by a tube end sidewall protrudes through an aperture in the plate to provide a joint for welding the sidewall to the plate in the region of the aperture. A welding arc is moved in a selected direction along a path of travel to form a weldment along the joint where the arc encounters the joint, while simultaneously reciprocating the arc back and forth in a crossways direction relative to the selected direction with an amplitude of reciprocation sufficient to encounter at least a portion of the joint lying to at least one side of the path to further form a weldment along the joint portion as the arc moves in the selected direction.

Abstract: A two-speed tuning machine for mounting on a hand-held, stringed, musical instrument has a first, relatively fast, gearing for rotating a post upon which a string is reeled during initial tensioning to a rough approximation of the desired final pitch, and a second, relatively slow, gearing, with its own separate input shaft, for rotating the same post during the final, precision tensioning to final pitch. A planetary-gear train having a relatively low gear-reduction ratio is used during the initial tensioning by applying manual rotation to an input shaft attached to the sun gear of the planetary-gear train, the planet gears being gang-coupled to rotate the post. The ring gear of the planetary-gear train is restrained during the initial tensioning by means of a worm engaging a worm ring on the periphery of the ring gear.