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Continued: Cast in the company's own foundry the bed was mounted on separate headstock and tailstock plinths and braced by a multiple of cross ribs with V-shaped tops to aid the dispersal of swarf. It also featured a strong central arch section and traditional flat and V-ways provided to guide the carriage. A removable gap section was fitted as standard (even on the optional long-bed model) and, when lifted out, allowed a disc 22 inches in diameter and 7 inches thick to be machined on the faceplate. Unlike many such gap pieces, the one on the Edgwick was machined with a positive location, so aiding its speedy and accurate replacement. Sealed with a full-sized, bolt-on cap the rectangular-form headstock contained shafts running in ball races and gears made from heat-treated, nickel-chrome steel. The spindle, bored through a generous 1.75 inches (44 mm) with a 4 Morse taper, was machined from a 42-tons tensile forging and carried in large, pre-loaded tapered roller bearings. Unfortunately the spindle nose was not an industry standard type but formed with a bolt-on flange - three 17/32" holes on a 4.75-inch pitch-circle diameter - so making chuck replacement a slow and tedious business. 12 spindle speeds were available, controlled by the juxtaposition of a single lever and a star-shaped selector handle - their positioning moving sliding gears. The drive passed through an easily adjustable combined multi-disc clutch and brake unit of Herbert manufacture that was mounted on the first motion (input) shaft of the headstock - operation of the clutch to disengage the drive automatically bringing the brake into action. A substantial lever, hinged on a bracket bolted to the front of the bed in line with the end of the headstock spindle, controlled the clutch/brake unit. No safety interlock or gate was fitted and to engage the drive the lever was simply pulled outwards whilst to disengage it (and apply the brake) it was pushed inwards. Lubrication of the headstock was positive, by a self-contained plunger-type pump that forced oil through a gauze and magnetic filter unit mounted on top of the headstock. Fitted with a sight glass the assembly also allowed the operator to see, at a glance, that the system was functioning correctly. Drive to the headstock was by four "A" section V-belts from a motor mounted on two pairs of slide rails set at 90-degrees to each other on the back face of the headstock-end plinth. With both the width and height spacing of the mounting rails being adjustable this arrangement allowed, within reason, a motor of almost any make or configuration to be fitted. The maker recommended two motors: a 3 h.p. 960 r.p.m. or a 5 h.p. 1440 r.p.m. - the former giving spindle speeds of 17, 26, 38, 59, 112, 172, 190, 225, 290, 430 and 670 r.p.m and the latter 25, 39, 57, 88, 170, 255, 280, 380, 430, 580, 650 and 1000 r.p.m. Grouped together on a sloping panel on the left-hand side of the headstock's front face, the electrical controls consisted of just 5 easily reached push-buttons. Continued below:
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