A deep throat chuck jaw system adapted to be used with a lathe with or without a headstock hole is provided. The system includes a set of jaw extension members having an inboard end supported from a face of a master chuck jaw coupled to a lathe chuck. The jaw extension members also include an outboard end. The set of jaw extension members are operable to grip an outer surface of a part having an outer diameter greater than the headstock hole with a clamping assembly clamped around the outboard end.