Abstract: A machine for cutting lengths of strip or tube from a moving length of strip or tube includes a carriage reciprocable in the direction of movement of the strip and mounting a cutter mechanism operable to sever the strip. The carriage is driven by a motor through a crank mechanism having a rotary input member. The motor speed is controlled so that during a substantial portion of one revolution of the input member the motor speed is constant and during the remaining portion of the one revolution the motor speed is controlled so that the linear speed of the carriage corresponds to that of the strip to be cut. During the latter period the motor speed is controlled in accordance with a plurality of secant values contained in a map.