Manufactured in the 1950s by Cantoni Macchine Utensili in Milan, the W51 was a toolroom-class lathe with a centre height of 180 mm and able to take up to 1000 mm between centres. Cantoni was a maker of many different machine tools including lathes, surface and cylindrical grinders, presses, guillotines, vertical and horizontal millers,, shapers, large horizontal borers, drills, hacksaws, tool and cutter grinders and Fellows and Pfauter-type gear-cutters.
The W51 lathe was made in two main sections: the headstock was cast as an integral part of the massive, left-hand support plinth, the bed being bolted to this and supported at the tailstock end on another large, cast-iron plinth. The bed had a front way of a type favoured at the time, this being of an asymmetrical pattern with a wide, shallow-angle way at the front to absorb wear and a more steeply-angled back to take thrust. For additional stability, the way at the rear of the bed was formed with narrow rectangular guides. Heavily built, the carriage had an apron with simple-to-operate, all-lever controls to select screwcutting and engage the power sliding, surfacing feeds. Fitted with a large micrometer dial, the cross slide was fitted with a pair of rear-mounted T-slots - to allow the fitting of a rear tool post - and a top slide able to be swivelled through 360°.
Published data was scarce but, driven by a 2-speed, 4.3.3.3 h.p. motor, the 38 mm bore spindle had 16 speeds that ranged from 30 to 1800 r.p.m. The motor, flanged-mounted against the inside face of the headstock-end bed-support plinth,  drove direct to a speed-change gearbox in the base of the stand. From there the drive passed, using four side-by-side V-belts, direct to the spindle. By this means, the makers aimed to isolate the spindle from vibration and so reduce the chance of 'gear marks' appearing on finely-turned work. Once the motor was running, electrical start, stop and reverse were operated by a "third-rod" system. The control lever for this was in the expected position - pivoting from the right-hand face of the apron - but, as this was a lathe with a relatively short bed, a second lever on the left-hand end of the control rod was not fitted.
Fully enclosed with control by levers - and no opening to admit swarf and dirt - the oil-bath-lubricated screwcutting gearbox could generate 18 Whitworth (inch) and 18 metric pitches. Unfortunately, the screwcutting and spindle-speed chart was mounted horizontally on top of the screwcutting gearbox, a location where it would inevitably suffer damage and become, in the fullness of time, unreadable.
Coolant equipment was built-in, the electrically driven pump being mounted on the inside face of the tailstock-end bed-support plinth and the storage tank within it. 
It appears that a quick-change toolpost was supplied as part of the standard equipment - as was a 4-jaw independent chuck, fixed and travelling steadies, a faceplate, an additional set of screwcutting changewheels, a tailstock chuck, two Morse taper centres and a set of spanners.
Weighing 1300 kg (1.3 metric tons), the lathe was 2310 mm long, 800 mm wide and stood 1020 mm tall..