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Manufactured between 1922 and 1935, the Newall lathe, with just a 2-inch centre height and 12 inches between centres - was something of a cross between an American-style WW watchmakers' type and a proper "precision bench" type. Whilst the latter closely resembled the Newall they were usually larger, more often being produced in sizes from 3" x 15" to 5" x 20" by firms such as G.Boley and Lorch in Germany, Schaublin and Mikron in Switzerland and a large number of American makers including B.C.Ames, Hjorth, Potter Pratt & Whitney, , Rivett, Stark, Wade, Waltham Machine Works, Wade, Pratt & Whitney, Rivett, Cataract, Hardinge, Elgin,, Remington and Sloan & Chace. The Newall was made by the Newhall Engineering Co. Ltd. of Blackhorse Lane, Walthamstow, London E.17 - with additional offices at 144 St. Vincent Street, Glasgow and publicity literature claiming representation in most of the world's industrialised countries. Founded in 1900, the Newall company enjoyed a long and illustrious history as precision engineers manufacturing items such as jig borers, grinders and inspection and measuring equipment including their well-known gauge blocks. The firm still exists today, as the Danobat Newall Group, specialising in rebuilding machine tools for the automotive and aerospace industries.
Locked to the bed by cam-operated bolts, the Newall headstock followed common practice in using a hardened and ground spindle running in a pair of hardened steel plain bearings that were finish-ground both internally and externally. The bearings were arranged with a steep taper to take thrust, a shallower taper to provide additional running area and with adjustment by a single ring at the end of the left-hand bearing whereby the running clearances could be set. The 4-step headstock pulley, intended to be driven by a round leather belt, followed the tradition of many contemporary watchmaker's lathes in being made from "Vulcanite", a propriety brand of hard rubber, with a steel plate fixed to the outer face of the largest diameter to carry a circle of 60 indexing holes. The pulley was arranged with its smallest diameter to the right-hand end, this design enabling the front bearing to be surrounded by a greater mass of material. The spindle did not carry a nose thread, instead all fittings - centres, chucks and faceplates - were by collet, pulled into place by a brass-handled draw tube. It seems that the makers saw fit not to offer the option of a lever-action quick-opener for production work.
Of solid section, the bed was supported on feet at each end and formed with a flat top and bevelled edges - the latter providing a location for headstock, slide rest and tailstock. The compound slide assembly was unusual - and in some respects advanced - having both the slideways and feed screws covered and a large-diameter zeroing micrometer dial on the cross feed. The top slide swivel was not quite 360 degrees, being restricted by the cross-feed micrometer dial, while the degree engravings only extended to 45 in each direction from zero. Integral with the top slide was a post that acted to both hold a toolpost and serve as a convenient mounting point for high-speed (overhead-driven) vertical milling and grinding spindles.
With lever-action only, the tailstock barrel was graduated with ruler marks and looks to have been equipped with the expected No. 1 Morse taper socket.
Supplied with each lathe was a T-hand rest in steel, a screw-feed compound slide rest assembly, an 8-screw "bell" chuck and a selection of 12 collets. Optional equipment offered included a 4-jaw chuck; milling or sawing arbors; a range of split and stepped collets; a faceplate drilled and tapped 2BA; tailstock drill chuck; "V" centres to support round bar for drilling; female centres; a travelling steady; a watchmakers' style drive countershaft; foot-motor; large headstock spindle mounted dividing plate; a vertical slide and high-speed milling and grinding attachments.
Newall were careful to extol the virtues of their organisation, explaining that not only was the lathe well-made and finished - nickel-plating and an enamel paint of the highest quality - but that the materials used in its construction had been tested for suitability by their own laboratories. Lathe were advertised (like Scott motorcycles) as being constructed to "Limit Gauge" and hence had parts that should have been interchangeable from machine to machine..
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