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One of many fine lathes produced by the famous German Weisser Company during the 1950s, the Model DW was a medium-duty machine built to a high standard and incorporating a number of interesting and thoughtful design details.
With a centre height of 130 mm (5") and taking 800 mm (31.5") between centres the lathe had a bed of enormous depth for its class that was fitted, as standard, with a removable gap that allowed work to 380 mm (15") in diameter to be turned. Power came from a 2.2 kW motor flange mounted to an Ortlinghause Gearbox that gave, in conjunction with the oil-sump lubricated geared headstock, 12 spindle speeds in low range of: 30, 45, 65, 95, 130 and 190 r.p.m. and in high range: 250, 375, 500, 750, 1000 and 1500 r.p.m. This arrangement of motor and gearbox, common on Weisser lathes of the era, was controlled by what might be described as a "generously long" automobile-style gear lever engraved with ratio positions on its red-knob-tipped end.
Running in high-precision roller bearings, the headstock spindle was fitted with a pulley overhung on its left-hand end, the drive rising from the speed-change gearbox by three V-belts. Although the spindle nose was formed with thread - when most competitors had long ago moved to more secure arrangements such as the American long-nose taper - for safe running in reverse nose fittings had a split thread tightened by a safety cross-locking bolt. Electrical control of the spindle stop and start was by a third-rod control with the operating handle pivoting from the right-hand face of the apron.
Guarding the changewheels and belt drive was an aluminium cover that included an unusual fitting: an intricate, cast-in drain pipe that caught coolant spilling from the back of the headstock spindle and directed it back to the storage tank.
Fitted with a conventional Norton-style quick change gearbox, a wide range of pitches was available, though to access them all some repositioning and substitution of changewheels was necessary, though as each was held by a spring-secured cap, they were very easy to change. Metric pitches ranged from a fine of 0.25 to a coarse of 7.5 mm; English Whitworth (gangen je zoll) from 3 to 32 t.p.i and MOD from 0.25 to 7.7. Power feeds, generated by a power shaft that drove worm-and-wheel gearing within an oil-sump apron, ranged from 0.036 to 1.07 mm/rev sliding with the cross feeds set at 1/4 the sliding. Drive to the leadscrew passed though a simple sliding dog clutch that allowed it to be disengaged and just the power-feed rod used.
Top and cross slides were both fitted with tapered gib strips with the large and crisply engraved feed-screw micrometer dials equipped with internal friction holders and knurled rims to aid grip by oily fingers. End play between the screws and their support flange could be adjusted by back-to-back locking castellated nuts. The 360° swivel top slide was secured in a circular T-slot (not the writer's favourite method - he has seen too many broken out) with two T-slots machined into the rear of the cross slide to hold a rear toolpost and travelling steady. In contrast to the fine engineering evident in the rest of the carriage assembly, instead of a robust clog-heel or 4-way toolpost, the makers supplied a very simple - indeed prosaic - spring-supported triangular clamp.
Slightly unusual in that the No. 3 Morse taper spindle passed right through the casting, the tailstock could be set-over for the turning of slight tapers. The spindle, engraved with mm divisions, was locked by a proper split-barrel compression bolt and secured to the bed by the usual arrangement of a clamp plate tightened by an eccentric cross-shaft turned by an extra-long handle.
Supplied with each lathe was a basic tool kit with a spanner, headstock bearing adjustment C-spanners, Allen keys, a clamp-on cross-slide depth stop for screwcutting and two changewheels, these able to be changed by simple pulling off their spring-retained fixing knobs..
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