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      email: tony@lathes.co.uk
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      Hogarth & Accura Lathes

      Hogarth V.L.15 production lathe


      Neither "Hogarth" or "Accura" were the name of a machine-tool manufacturer but a brand used during the 1930s by an English import company - almost certainly Soag Machine Tools of London SE2. The lathes were then offered directly to end users, badged "Accura" or, for distribution through larger and more successful independent dealers such as Percy Martin of Leicester, as "Hogarth". It is entirely possible that other names were used as well - reflecting a situation almost as confusing as that during the later years of the 20th century when machines from the Far East arrived packed with a selection of spurious brand-name labels for the importer or wholesale dealer to affix. 
      Of the known types, six variations on a single model of the "Hogarth" were offered: the almost identical VR-18, VRZ-21 and VRA-23 versions of 7, 8.25 and 9-inch centre height respectively and a range of lathes badged VR-21, VRZ-23 and VRA-25 that, whilst looking very similar, were of generally more massive proportions and heavier build. Soag appear to have advertised only one version of the "Accura", the Model DH-17, a machine identical to the "Hogarth" VRZ-21 in all but its 17 to 750 rpm speed range. Of amazingly clean, angular lines for their era all these lathes would, if mounted on full cabinet stands, still not have looked out of place in the late 1960s. A rather different "Hogarth", a production version, the V.L.15, with a limited number of speeds and feeds, was also listed.
      For both size groups quite why such differing model designations were used is a mystery for, apart from the height of the headstock and tailstock castings (and presumably the necessary alterations to saddle, cross and top slides to adjust the tool height) each machine (in the two groups) was identical to the others and shared the same bed, headstock contents, screwcutting gearbox, apron, leadscrew, powershaft and even (when fitted) size of electric motor. As a concession to size, and to allow better use to be made of the gap-turning capacity, the speed range of the VRA-23 was slightly modified from the 15 to 650 rpm of the smaller pair to 12 to 540 rpm. The VR-18, VRZ-21 and VRA-23 lathes had a V-way, chilled cast-iron bed 11.375-inches wide with heavy cross bracing and to a Brinelle hardness of approximately 200. The carriage ran on the outer pair of Vees and the tailstock on an inner V-way and flat. All equipped as standard with a detachable gap piece with the maximum diameters that could be turned being (respectively): 21.5-inches, 24-inches and 25.5-inches - and the greatest thickness that could be accommodated on a faceplate the same, at 8-inches, for all machines.
      Continued below:

      "Hogarth" Model VR-18. The VRZ-21 and VRA-23 versions of the lathe were both of almost identical appearance

      Continued:
      The 12-speed oil-bath headstock was of interesting construction with the 2-inch bore spindle in a tough steel, ground finished and running in a pair of parallel-bore bronze bearings tapered on their outside to allow for adjustment by serrated ring nuts and with end thrust taken by a ball race. The main drive gear was of a "semi-helical" form, keyed to the spindle in the usual place immediately behind the front bearing. The three headstock layshafts all ran on ball races and carried hardened nickel-chrome steel gears with the input shaft at the rear carrying two multi-plate clutches - in a manner eventually adopted by Colchester in the 1960s - and by which means the spindle could be instantly started, stopped and reversed by a single lever on top of the headstock. The headstock was closed by a rear-hinged cover that fitted into a lipped recess arranged around the periphery of the opening; in the bottom of the recess was a series of drain holes to return lubricant that had leaked passed the edges of the lid. Leadscrew reverse gears, controlled by a lever, were positioned on the inside of the headstock, where they benefited from the headstock oil supply. The headstock could be arranged for drive by either flat belt from an overhead line-shaft system - in which case the input pulley was 8-inches in diameter and 3.125-inches wide - or by a motor fastened to an adjustable plate on the back of the bed in which case a V-pulley was used.
      The compound slide rest was fitted with taper gib strips and both top and cross slides had micrometer dials of - typically for the era - far too small a diameter.
      The oil-bath screwcutting gearbox was of the Norton quick-change type and able to generate a useful 40 English pitches from 2 to 28 t.p.i and, with the aid of extra changewheels, 24 metric from 0.5 to 9 mm pitch. Unusually, the box was fitted with a coarse-threading attachment whereby a 2 or 16-times increase in pitch could be obtained - though the drive was still taken down the standard 1.375-inch diameter by 4 t.p.i. leadscrew rather than through an auxiliary shaft at the back of the bed as was sometimes used by other makers.
      The apron was of the proper double-wall type with the all-steel gears running in oil splashed up from a sump supply. Power sliding and surfacing feeds were provided by a separate keyed power shaft geared from the leadscrew just outboard of the screwcutting gearbox. The shaft passed through the usual type of worm-and-wheel mechanism connected to a train of gears whose selection and engagement was controlled by a single 3-position quadrant lever on the face of the apron. There was no engagement clutch and, whilst the sliding feed could be automatically disengaged by an adjustable collar on the power shaft (but only when moving towards the headstock), the cross feed could only be stopped by returning the engage/selection lever to its central position. Sliding rates of feed varied from 0.0031 to 0.047-inches and surfacing from 0.0016 to 0.024-inches per revolution of the spindle.
      The set-over tailstock was heavily built with a 1.75-inch, 3-Morse taper barrel with a double clamp.
      All models were available with 30, 40 50 or 60 inches between centres and weighed from 2050 lbs for the shortest bed VR-18 to 3400 lbs for the longest bed VRA-21.
      The heavier machines, catalogued as the VR-21, VRZ-23 and VRA-25 had centre heights of 8.25, 9 and 10-inches respectively with the ability to turn in their gaps a disc of material 9-inches thick and, respectively, 25.5-inches, 27-inches and 28.5-inches in diameter.
      Although the lathes all used a bed that was, at 12.75-inches, wider and heavier than that used on the smaller range the headstock internals and its bearings were identical - though the 12 spindle speeds were arranged to be slightly slower at between 12 and 540 r.p.m. and a 4-step V-pulley was used from the 4 or 5 h.p. motor. Although the screwcutting gearbox, powershaft and apron also appeared to be identical the feeds were slowed slightly to between 0.0039 and 0.059-inches per revolution of the spindle sliding and 0.0020 and 0.0276-inches surfacing.
      Available bed lengths gave a choice of 40, 50 or 60 inches between centres with weights varying from a low of approximately 2640 lbs on the short-bed VR-21 to a maximum of 4530 lbs for a long-bed VRA-25..


      Hogarth VS18 - the flat-belt drive version of the VR-18

      The oil-bath headstock  had a 2-inch bore spindle in a tough steel, ground finished and running in a pair of parallel-bore bronze bearings tapered on their outside to allow for adjustment by serrated ring nuts and with end thrust taken by a ball race. 

      Simple diagram of the Hogarth's geared headstock

      The apron was of the proper double-wall type with the all-steel gears running in oil splashed up from a sump supply. Power sliding and surfacing feeds were provided by a separate keyed power shaft geared from the leadscrew just outboard of the screwcutting gearbox.

      Optional taper-turning attachment. Note the large pressed-steel swarf guard


      Hogarth V.L.15 production lathe

      Hogarth & Accura Lathes
      email: tony@lathes.co.uk
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