Workholding

When it comes to workholding, one size definitely does not fit all. For example, workholding setups for round parts have similarities to setups used for all other prismatic (nonround) parts, but the latter has unique challenges.

The August 2012 Workholding column defines the many chucks used for turning.

Part manufacturers are examining every aspect of the production process, from cutting tool parameters to workholding methods, to find ways to reduce costs and improve quality. Conversations with metalworking professionals have revealed a heightened awareness of the role that nonmachining changeover time plays in manufacturing costs. Shops know that speeding changeovers can save them money every time they switch a setup or move a part.

Since the dawn of CNC milling, machinists have been trying to squeeze more parts onto the table and position them quicker. That’s because to a machinist, it’s all about reducing setup time and cranking out more parts per hour.

There are numerous advantages to rigidly holding a workpiece: feed rates can be increased and cutting times reduced, cutters last longer and impart finer surface finishes, and more-accurate parts are produced. At trade shows where vendors offer demonstrations, you rarely see flimsy, difficult-to-hold parts being machined. In the real world, however, such parts are common. Holding parts for secondary operations, such as drilling holes on an edge, can also be challenging.