Abstract: Contouring of a stack of one or more circuit boards is effected by first partially cutting the contour, leaving a portion of the contour long enough to ensure the rigidity of the circuit with respect to the board. The circuit is then clamped, while the remaining portion is cut without any discontinuity in the cutting. The machine comprises an operating head and a workpiece pressing pad which is operated for clamping the circuit during the cutting of the remaining portion of the contour. The pad is movable with respect to the head in a direction parallel to the uncut portion of the contour for displacement at least equal to the length of such portion. After the cut, as the head is raised, the pad is returned to rest position by the camming action of a roller against a sloping edge.