Lexair (Lexington, KY) has announced the Lexair/ Production Dynamics Full Bore® chuck, a mechanical-grip, air-release, front-mounted collet chuck designed to make the full spindle bore available to handle larger bar stock. The design eliminates the conventional draw tube and external actuator. Air is used only to open the chuck. Spring force holds the workpiece while it is being machined, and the part remains clamped even if air pressure is lost. Since clamping force is constant regardless of spindle speed, higher speeds can be reached during machining. Clamping force is adjustable by tightening or loosening the collet using the spanner holes.
The chuck features adjustable concentricity and dead-length positioning to allow hex, round, and square bar feeding with fast collet or pad changes. Pads are available in 1/16" increments for round, smooth stock and most sizes for round serrated, hex, and square stock. It is available in nine models with diameters ranging from 6.75" to 14".