Lexair (www.lexairinc.com) Production Dynamics full-bore chucks are available in nine models with diameters from 6.75 in. to 14 in. The company says the chucks make full spindle bores available to handle large barstock. The air-release, front-mounted collet chucks grip mechanically and eliminate conventional draw tubes and external actuators.
The chucks are designed to be opened by air, and spring force holds workpieces during machining. The company says parts remain clamped even if air pressure is lost. Lexair says that clamping force is constant regardless of spindle speed, making high machining speeds possible. Clamping force is adjusted by tightening or loosening the collets using spanner holes.
The chucks have adjustable concentricity and dead-Iength positioning to allow hex, round and square-bar feeding with fast collet or pad changes. Pads are available in 0.0625-in. increments for round, smooth stock and for most sizes of round serrated, hex and square stock.