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Continued: Although all early models had the No. 5 Morse taper headstock spindle running in plain parallel-bore, taper-outside phosphor bronze bearings, later models were offered with the option of Timken taper-roller races. The headstock gears were manufactured from carbon-chrome alloy steel with 0.55/0.65% carbon, 0.3% silicon, 0.5/0/8% manganese and 0.45/0.7% chromium. Driven by 2 V-belts from a 2-h.p. 3-phase motor the rather slow spindle speeds of 30, 47, 77, 126, 179, 284, 463 and 750 rpm were controlled by three levers, mounted on the front face of the headstock and moving through quadrant arcs. The lever on the right selected either the high or low speed ranges whilst the two on the left (interlocked to prevent two gears being engaged at once) controlled the 4 individual speeds in each range. The headstock contained a multi-plate reversing clutch that could be operated, through a third-shaft control rod, from either a lever connected to a bevel box just to the right of the screwcutting gearbox or a rod pivoting from the right-hand face of the apron. Whilst the headstock gears relied on an inexpensive and simple splash system for lubrication the clutch, which was under considerable stain, was provided with its own pumped supply. Equipped as standard with a conventional "Norton" pattern quick-change gearbox, the lathe could generate 27 pitches and feeds with a further 27 available by the simple expedient of swapping over two gears on the drive arm. A range of other changewheels (with a 20-degree pressure angle) was supplied to allow a wide range of metric pitches to be generated, these included: 30t, 45t, 55t, 60t, 65t, 70t, 75t, 120t and 127t. The 11/8-inch diameter 4 t.p.i Acme-thread leadscrew was fitted with a dog-clutch at its headstock end and was normally left disengaged. The power shaft drive was protected by a strong spring-assisted "over-ride clutch" held inside a sleeve where the shaft entered the gearbox. Of conventional design the apron used worm-and-wheel gearing, driven by a slotted, key-carrying power shaft that transmitted drive to a train of gears that could be directed to give either power sliding or power surfacing. Selection of the feed direction was by lifting or lowering a centrally-mounted quadrant lever and engagement by a concentrically-mounted a screw-in-and-out knob that engaged a cone clutch.. Sliding power feeds varied from 0.002" to 0.036" per revolution of the spindle with the surfacing rate set at 1/3 of the same range. The top of each rather narrow saddle wing was fitted with T slots that allowed the travelling steady to be given a wide and hence stable base. The compound slide rest was fitted with proper tapered gip strips and the cross and top slide travels were 81/2-inches and 63/4" respectively, both driven by a respectably-large 5/8"-diameter 8 t.p.i Acme-form feed screws; however, on the machines illustrated, the micrometer dials were far too small. 15/8-inches in diameter, the tailstock barrel was fitted with a No. 3 Morse taper; it's five inches of travel were marked by engraved lines and drive was by a 3/4-inch diameter left-hand Acme-form thread. Unfortunately the nut used to clamp the tailstock to the bed required the use of a loose, self-hiding spanner. As supplied from the factory the lathe was equipped with: the main driving motor, switchgear and belts, fixed and travelling steadies, a thread-dial indicator, 4-way toolpost, an electric suds pump and receiver tank, faceplate, catchplate, changewheels for metric screwcutting, a rear splash guard, one pair of headstock and tailstock centres and oil gun and instruction book. With an overall length of 83-inches long the standard model weighed 16 cwt (1792 lbs/812 Kg) whilst the long-bed version was 1161/2" long and weighed, at 20 cwt (2240 lbs/1016 kg) some 25% more..
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