Abstract: A probe for touch sensing to determine the position of a workpiece in a robot welding system using a robot driven welding gun for advancing a welding wire in a given direction toward a workpiece. The gun is movable by a robot controlled arm in a selected weld path and the probe comprises a rigid, elongated feeler with a touch tip which feeler is carried by a mechanism fixed with respect to the gun and movable by the mechanism between a retracted position and a known extended position wherein the feeler extends from the mechanism a fixed distance having an outermost contact point for the touch tip where the point has a known spatial relation to the gun. A detector detects when the contact point touches the workpiece to locate the workpiece. Several touches are used to determine the orientation of the workpiece for automatic welding.