taper for either the collet's male outer taper, or a sleeve that will hold it. A hollow drawbar passes back through the headstock to its back side, where a closer mechanism is mounted. The latter allows easy, rapid opening and closing of the collet. The drawbar's inner diameter determines the through-the-spindle bar diameter capacity of the lathe. Some collet-closer systems even allow opening and closing without stopping the spindle rotation. The closer on a manual lathe is either lever-style or handwheel-style. The closer on a CNC lathe is powered (electric, hydraulic, or pneumatic), and it may be controlled by various means: a foot pedal that the operator steps on when desired; a line in the program (for opening and closing under program control); or a button on the control panel. History The original forms of workholding on lathes were between-centers holding and ad hoc fastenings to the headstock spindle. The spike-style centers still used on wood lathes represent an ancient method. Ad hoc fastening methods in centuries past included anything from pinning with clenching or wedging; nailing; lashing with cords of leather or fiber; dogging down (again involving pinning/wedging/clenching); or other types. Faceplates have probably been around at least since the era of medieval clock-makers. Tooling similar to today's chucks seems likely to have evolved from faceplate work, as workers using faceplates for repetitive work began to envision types of clamps or dogs for the faceplate that could be opened and closed in more convenient ways than repeated total disassembly and reassembly. A chock was originally just a lump of wood. However, by 1703 it could be "… Chocks, belonging to the Screw-Mandrel". By 1807 the word had changed to the more familiar 'chuck: "On the end of the spindle … is screwed … a universal Chuck for holding any kind of work". In late 1818 or early 1819 the Society for the Encouragement of Arts, Manufactures and Commerce awarded its silver medal and 10 guineas (£10.50 – ) to Mr. Alexander Bell for a three jaw lathe chuck: It is not clear how they were moved "equably" whether by a scroll or some other means. Later in 1819 the same body awarded a further silver medal to Mr. T. Hack for a four jaw chuck. In the United States Simon Fairman (1792–1857) developed a recognisable modern scroll chuck as used on lathes. The patent refers to the technicalities of