Abstract: A workholding chuck that allows for a sizable gripping range by utilizing a rotary clamping method with dual stage motion. The dual stage rotary gripping chuck allows small diameter parts to be clamped, as well as parts that are larger than the main chuck body diameter. The dual stage motion allows resistance to be first achieved by lightly clamping on a workpiece, which is then converted to a high force-to-movement ratio. The workholding chuck employs two helical connections that allow for a large gripping diameter variation with a short amount of axial travel.