A chuck jaw having a sensor jaw body and a sensor. A first supporting face and a second supporting face for a chuck insert are formed on the sensor jaw body, which supporting faces are not oriented parallel to each other and are connected via a notch. The sensor is provided in duplicate as strain gauges which are arranged laterally on the sensor jaw body. A chuck insert and a chuck are also provided.

The present disclosure provides a jaw assembly for mounting to a lathe spindle. The jaw assembly comprises a first jaw set with at least one axially extending jaw portion which comprises a channel extending in the same axial direction as the jaw portion, and a second jaw set locatable within and releasably attached to the first jaw set via at least one fastener locatable in the channel.

A chuck jaw includes a foot portion configured to be mounted on a chuck body, a jaw body configured to hold a workpiece, and a metal layer provided on the jaw body such that the jaw body is configured to hold the workpiece via the metal layer. The metal layer includes a first metal material that has a thermal conductivity lower than a thermal conductivity of a second metal material which the jaw body includes.