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Continued: Large enough to accept No. 5-Morse taper, the 1.5625" bore headstock spindle was sleeved down to 3-Morse (with the usual short taper sleeve) and the nose equipped with an American standard LO size taper-key nose - although early machines had a screw-thread nose. The spindle ran in taper-roller bearings and was driven by a single-speed, 2 h.p. 3-phase motor through 9 speeds spanning 52 to 954 rpm. As an option, on late models, a high-speed range from 84 to 1550 rpm could be specified or, with a two-speed 2 and 3 hp motor, 42 to 1550 rpm. A lever on top of the headstock operated a clutch when moved sideways and a spindle brake when pressed down; later versions were given an improved mechanism recognisable by a large quadrant-shaped housing surrounding the clutch-lever pivot point. Very late models also enjoyed an improvement to the spindle-speed selection levers where, instead of being vulnerable to accidentally engagement by a stray hand, had to be pressed inwards against spring pressure before they could be moved. On these lathes the clutch was removed and its operating lever used instead to operate an electrical switch and a brake--the effectiveness of which was proportional to the (firm) force exerted on its operating lever The system was combined with push button control - one each for forward and reverse and another for "inching" and all mounted on the front face of the changewheel cover. These late machines can easily be recognised by a sector-shaped speed-chart cover over the spindle speed levers. 13/8" in diameter, the 5 t.p.i leadscrew drove an oil-immersed screwcutting gearbox that gave 40 English and, with the deployment of a 125/127T pair, 8 metric threads (though one of these, being a non-standard 0.625 mm pitch, was there just to make up the numbers). Unusually for an affordable English-specification lathe of the period, the metric screwcutting was available "on demand" - this being achieved by bringing into mesh (by simply moving a single lever) the 125t gear that revolved on the same spindle as the 127 (the two gears, though having different numbers of teeth, were made the same diameter so they meshed with the 50t gear without having to adjust the setting of the changewheel bracket). Two extra gears, 49t and 54t, were available, if required, to further the metric threading range. On some versions, the sliding feed was fitted with an automatic knock-off control arranged by the simple expedient of mounting a sliding stop on the front edge of the trip tray that caught against the power-feed engagement lever that protruded from the base of the apron. One small problem concerned the engagement of the (single-sided) leadscrew clasp nut; the profile of the cam slot for closing it was so "abrupt" that it could be difficult to release under a heavy threading load. In addition the changewheel banjo was (incomprehensibly) pivoted at the wrong (driver) end, making it unnecessarily laborious to fit the substitute driver gears for metric pitches. Later-model slant-beds (before the sector-shaped spindle-speed covers) can be recognised by a revised screwcutting gearbox with its line of indent holes below rather than above the selector lever. Cross and top slides were heavily built and equipped with thrust-bearing-equipped and particularly robust 3/4" x 5 t.p.i. feedscrews, a specification that promised slow wear and a long life. On some examples of the lathe an unusual cross and top-slide-gib arrangement was used where, instead of a loose gib strip and adjustment "pusher" screws, a pair of long gib "blocks" was fitted, each held into the roof of the slide by downward fitting screws with their heads counter-bored into the latter's top face. Unfortunately, unlike the similar arrangement used on a Myford Super 7, no sideways adjustment screws were fitted - indeed, no correction to the fit was possible, each section of gib block being simply scraped to a fit on its dovetail side and on the three thrust 'pads' that contacted the roof of the slide. As wear took place, and play developed, it would have been necessary to remove the bocks and effect repairs. One owner managed this by fitting ground shim stock under the gib blocks and then machining the mating faces to remove uneven wear and bring their underside of the loose to the same level as the dovetail on the other side. Side-mounted grub-screw were also fitted (along Super 7 lines) to enable fine adjustment and compensation for future wear. Heavily built, the set-over tailstock had a No. 3 Morse taper barrel 11/2" in diameter and with a travel of 5 inches. Later lathes had a more robust unit with a V-shaped slideway formed between sole-plate and upper casting. As appropriate for a machine intended for educational use a safety interlock was provided on the changewheel cover and, if the right-hand cupboard door was locked, the machine was electrically isolated. One useful feature not appreciated by owners who failed to read the manual on page 12), was that as the splash-back cover was hinged down it formed a nifty swarf hopper. A wide range of accessories was offered, including some rather unusual ones. Besides the expected range of accessories that included large faceplates, fixed and travelling steadies, collets, 4-way and quick-set toolholders, dead-length fixed and micrometer stops, a toolpost grinder, a vertical milling slide (etc), and one or two out-of-the-ordinary ones were also listed including a taper-turning and profiling attachment that could be used on the top slide, an unusually arranged hydraulic copying attachment and, strangest of all for a machine produced into the 1960s, a con-rod boring jig. The 24-inches-between-centres lathe was 67" long, while the 36-inch capacity version was, naturally enough, 12 inches longer; the width was 36", the height 52" and the weight 1400 lbs and 1530 lbs respectively. Shown on another page is a different version of the "Slant-Bed" - identical in almost all observable details but with the bed ways set level in the conventional way. This machine was branded (using the term "straight bed") as both a Willson and, later, Elliott - in the latter case as the "Mark 1N" with a 7-inch centre height and, in what must have been the first type produced, as the 6.5-inch "Mark 1U". From 1959 a now seldom-found 12-inch centre height Big slant bed listed as the Mk.11 manufactured, this having a 3-inch bore spindle with an L2 nose and 18 speeds from 12 to 580 r.p.m..
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