Abstract: A rotatable workpiece holding collet having flexible fingers defining an interior workpiece gripping surface intersecting the collet fingers' free end, the portion of the gripping surface adjacent the collet free end being obliquely disposed to the collet axis of rotation to function as a guide surface permitting workpieces to be inserted into the collet during rotation.

Abstract: The invention pertains to a system for the co-extrusion of multiple layers of thermoplastic material. The invention employs a modular system concept which enables a manufacturer to quickly exchange components to accept melt flow from a number of extrusion injectors to provide a number of extrudate layers for shaping by a standard sheet extruder die.

Abstract: A multiple faced cutter insert usable with lathes and turning machines, shapers, planers or milling cutters having a plurality of cutting edges associated with chip forming recesses. The adjacent cutting edges and lateral faces intersect at corners free of a radius and the chip forming recess associated with each cutting edge adjacent a corner produces chip flow at the corner substantially perpendicular to the associated cutting edge and recess. Preferably, the insert is of a regular pentagonal or hexagonal configuration to provide extensive support of each insert cutter corner to minimize corner breakage.