A ball mounting method for mounting a plurality of balls held by a head
onto a workpiece. The head is clamped such that a clamping surface
mounted to the head is engaged with a rigid lower positioning stop, and
then moved above a ball supply section. The balls are held on the head,
and the head is moved above the workpiece. The clamping force is then
released so that the clamping surface does not engage the lower stop, and
the head is counterbalanced between the lower positioning stop and an
upper positioning stop. While the head is unclamped and counterbalanced,
the balls are mounted on the workpiece. The head is then clamped and
moved above the ball supply section again.