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CVA made a range of high-class machine tools including automatic gear cutters, gear hobbers, automatic and small capstan lathes, dieing presses, milling and die-sinking machines, pantograph engravers and a small jig borer. However, CVA made only a limited range of conventional lathes: their first was the little round-bed "CAV Wade", designed for the lower end of the amateur market (a machine that was to remain in production until the late 1930s) a number of small plain-turning precision bench and capstan types and a much larger toolroom model closely modelled on the fabulous American Monarch 10EE (the latter was introduced during the late 1930s and remained in production until around 2010. The equally beautiful CVA version was made in England from the 1940s until the late 1980s - when they were still available from the then manufacturers, formerly E.H.Cole and then possibly as H. Cole & Sons of Curtis Road, Dorking, Surrey for £28,700, plus another £2960 for the taper turning unit. C.V.A. began life in 1917 as C. A. Vandervell & Co Ltd. (C.A.V.) to produce materials For WW1, including a range of munitions. As the Company grew (and doubtless took on other work), a foundry was added in January 1926, and then, in December 1929, plans were announced to expand this and add a heat-treatment shop - the facility opening in early 1930. With a further name change in 1934 to C.V.A. Jigs, Moulds & Tools Ltd., the firm flourished throughout WW2 and, by its end, was well positioned to re-enter the civilian market. Its heyday came during the 1950s when, in 1953, for example, it was so busy it had no fewer than 73 apprentices. Eventually becoming part of the American Kearney & Trecker Group, the CVA part was sold off - with a final change of name to F.M.T. and a winding down of the Company during the 1990s. Always an expensive machine, from 1948 to 1953 the toolroom CVA sold (depending upon equipment) for between £700 and £1000, a sum that would, at the time, have bought a very good house in the better parts of any UK city. For its final form, Coles proposed fitting a CNC control system; however, only very limited numbers can have been made and the one installed in a Trowbridge college during the 1980s was reported to the writer as not being up to contemporary standards and lacking in power.Constructed as an uncompromisingly accurate and finely detailed machine tool, the original CVA occupied about the same floor space as a Colchester Student but, with its cast-steel stand, weighed over three times as much. So confident were CVA in the rigidity of the machine that the stand's three floor-mounting points (two pads at the headstock end and one at the tailstock) had no provision to mount anti-vibration pads - however, if a machine was to be (unwisely) installed on other than a level floor, the makers advised that it be packed up with metal shims. To insulate the headstock spindle from vibrations associated with gear drive, the electric motor, spindle-speed gearbox and clutch unit were remotely mounted inside the base of the machine - and drove the headstock through multiple V belts on early versions and, for greater smoothness, a flat belt on later models. Three different ranges of twelve spindle speeds were offered: Range A gave 25 to 1645 r.p.m, Range B 29 to 2220 r.p.m. and Range C (at extra cost) 40 to 3100 r.p.m. When sliding and surfacing feeds were selected (by individually clutched levers on the apron face - another beautiful touch), the drive, as on some Lorch and Schaublin lathes, was transmitted not through the screwcutting gears but by belt to a separate gearbox. This latter system provided much finer feed rates, especially at high spindle speeds, and also prevented the transmission of "gear marks" to the workpiece drive and saved wear and tear on the screwcutting mechanism. Taper turning, of a unique design, incorporating adjustable ball bearings to the slides and the ability to set tapers to within one minute of arc, was fitted as standard - and, because it incorporated a telescopic screw, it was possible to use the cross slide with the taper turning engaged. A "post-production" CVA appears to have been made in very limited numbers, possibly during the early 1980s. These lathes featured a massive 10 hp DC motor with a complicated control system, driving through an expanding and contracting pulley system, the movements of which were chain-driven from a 0.5 hp electric motor. The top speed was 3000 rpm. Because of its standard-fit clutch, the standard CVA is one large lathe which works well when converted to single-phase electrics - and numbers are now finding a second life employed in the private workshops of those model and experimental engineers who appreciate being able to use a precision lathe constructed initially without regard to cost. Over the years, various small changes were made to the specification and the maker's Model designations. However, these appear to have been few in number and - apart from the restyling to a square-look appearance - and rather minor. For example, in the Series II brochure, one option was a set of screwcutting changewheels to generate 19 t.p.i. However, the Series III manual (maker's code PD1143) listed the lathe as having 19 t.p.i on the standard feed-selector dial - it would appear that when the decision was made to change the rounded Series I styling to the angular (as we see on the series III) the plan would have been to include 19 t.p.i. in the gearbox For whatever reason this did not happen immediately so, the new styling was designated as the series II (with no change to the gearbox) and a short time later the new gearbox (and possibly the change to flat-drive belt) was introduced as the Series III. Even so, to great confusion, some Series 3 machines have been found without the 19 t.p.i. pi feed - possibly caused by a glitch in the production process or even a mistake by the maker. For a fuller explanation of how the CVA was originally conceived and developed see the American monarch 10EE section of the archive Continued below:
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