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Similar to the Kovo S28 (built from the early 1950s) the TOS S28 was current during the 1950s and 1960s and the Company's smallest "toolroom-class" lathe. With a centre height of 5.5" and admitting 30" between centres, it was, at 2400 lbs (just over 1 tonne) very heavily constructed and mounted on a massive cast-iron stand with a chip tray and central storage cupboard. Formed as one rigid casting, the headstock and screwcutting gearbox assembly was bolted to a 9.875-inch wide bed that carried flat and V-ways. As with many TOS machine tools built under communist control in what was then Czechoslovakia, the lathe may well have been constructed at more than one location including Kovo Hodonin and at TOS Zebrak. Running in adjustable bronze bearings, the 1.375" bore spindle was driven though a multi-disc clutch by a powerful 4 h.p. motor flange mounted against the left-hand face of the headstock-end plinth and will all its electrical controls neatly built in. A total of eighteen speeds were provided, in three ranges, that spanned a most useful 20 to 3150 r.p.m. Lubrication of the headstock gears and bearings was by a gear-type pump mounted in the lower part of the casting Totally enclosed and with control by rotary dials and levers, the screwcutting and feeds' gearbox gave a range 36 of sliding feeds from 0.001" to 0.138" and 36 surfacing from 0.0004" to 0.47" - a useful safety feature was the provision of adjustable, automatic disengage of both feed directions against positive stops. Screwcutting covered all the usually required forms, those these did require the substitution of different changewheels, and covered 36 Whitworth pitches from 0.75 to 88 t.p.i., 36 metric from 0.375 to 44 mm and 36 module from 0.375 to 44 mm. As was usual with machine tools from communist-controlled countries desperate for Western currencies, the standard equipment was generous and included the main motor and its controls, a taper turning attachment, 6 collets from 1/4" to 7/8" in 1/8" intervals and the necessary draw tube, full coolant equipment, changewheels, a 4-jaw chuck arranged as a slim faceplate, 3-jaw self-centring chuck, fixed steady, travelling steady, 4-way toolpost, rear toolpost, micrometer carriage stop, two Morse centres, a reducing sleeve for the spindle, a set of spanners and an instruction book..
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