Abstract: Cutting width modifying means for a machine for cutting a web of material and having groups of cutting elements of the bottom blade kind for longitudinal cutting of the web wherein the cutting elements are provided as sleeves mounted on a shaft, releasably secured against rotation thereon by keys and axially adjustable by means of externally screw threaded rings mounted in screw threaded portions of the bores of the sleeves and non-rotatably secured on the shaft, retaining means being provided selectively to retain one or more of the sleeves against rotation so that it or they is or are axially adjusted on the shaft upon rotation of the shaft by a servo motor.