Hardinge offers a selection of 5C spindle tooling, including collets, step chucks, emergency collets, fixtures, face plates and expanding collet systems, as an alternative to common gripping methods. Its Sure-Grip system can be used for OD grinding. The expanding collet performs parallel gripping with immediate centering of the workpiece, the company says. The product can accommodate work from 1/8" to 4" in diameter. It is also possible to access the full grinding length of the workpiece. According to the company, the hardened and ground expanding collet head can be reground in place to the desired size to the most appropriate concentricity scenario to achieve zero TIR. It can later be reground or recycled to accept a smaller ID workpiece for a different job setup. Expanding collet heads of varying sizes fit on the same collet body, and they can be changed from the front without removing the collet body. Among the potential benefits cited by the company are decreased setup time because of instant centering without individual clamping; a small, light unit that can be mounted relatively easily; and achieving high levels of accuracy. Collets are available in 1/64" increments, as well as in a range of metric sizes. The range of each collet is +0.015” to -0.001” (+0.38mm to -0.025mm) from its specified size. The company’s expanding arbors can be used between centers instead of tapered arbors to grip more contact area.
Also available from the company are pin step chucks, “extra-depth” step chucks, customized spindle fixtures, blank fixture plates, universal faceplates and a range of workholding products for ID, OD, universal, tool room, cutter and drill and jig grinding machines.