Direct Drive is another variation of friction welding, where one workpiece is held in a motor-driven spindle and rotated at a pre-determined speed whilst being pushed against the second workpiece which is restrained from rotating. After a fixed time period or after a known amount of shortening of the workpieces has taken place, the heat required for welding is generated by friction. Rotation is then stopped, the axial force between the workpieces is increased and the weld is completed.