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Continued: On the LZ version, screwcutting and power sliding and surfacing feeds were provided by (in comparison to other lathes in the maker's range) a simplified oil-bath lubricated gearbox with the most highly stressed gears hardened, all shafts running in ball or roller races and control by just two rotary knobs. Without altering the changewheel set, a limited range of just fifteen screwcutting pitches from 0.25 to 5 mm were available with the same number of power sliding feeds that ranged from 0.03 to 0.3 mm (0.0018" to 0.01881") per revolution of the spindle using the standard changewheel set (with power cross feed at half those rates). However, extra gears were available that, when fitted, gave a better range from 0.02 to 1.0 mm. With the necessary transposing changewheels fitted, inch pitches from 5 to 96 t.p.i. and Mod from 0.25 to 4 MOD could also be generated. Although relatively short in terms of its saddle length, the carriage assembly was, nevertheless, beautifully constructed, Doubled-walled, the apron used shafts supported at both ends in anti-friction bearings; oddly, unlike the contemporary but larger and more expensive Praktikus L (which used a slotted leadscrew to provide both the screwcutting and power-feed drives) the Primus had a separate powershaft. Both leadscrew and powershaft ran, at both ends, in anti-fiction bearings with drive from the exposed leadscrew picked up by the usual type of double clasp nuts. Sliding and surfacing feeds were selected by a push-pull knob - with the middle neutral position engineered to allow engagement of the leadscrew clasp nuts. Feeds were engaged by lever through a form of clutch first introduced pre-WW2 on American lathes, the mechanism incorporating what Weiler described as a "ball sliding clutch" to protect the drive. Fitted with a large micrometer dial, the carriage handwheel gave a travel of 15 mm (0.6") per revolution. Full length - and so better able to even out wear over its ways that a short type - the cross slide had a generous 150 mm (5.9") of travel and was topped by a 80 mm (3.1") travel tool slide able to be swivelled through 180°. Both slides were fitted gib-strip adjustment screws on very close spacing and driven by hardened, trapezoidal-form feed-screws running through wear resistant "PAN-bronze" nuts. The zeroing micrometer dials were of a decent size, dull-chrome plated and crisply engraved at intervals of 0.02 mm. Between the top surface of the tool slide and spindle line was a gap of 22 mm (0.87") that allowed tools up to 14 mm (0.55") deep to be held in the maker's quick-set toolpost. One (expensive) option for the carriage assembly was an infinitely-variable speed drive - this being provided by a motor flange mounted against the face of a step-down gearbox at the tailstock end of the bed. Fitted with a captive handle and an eccentric bed lock, the set-over tailstock held a hardened and ground No. 2 Morse taper, 30 mm (1.2") diameter spindle with 80 mm (3.1") of travel and graduated with ruler lines on a 1 mm spacing. Running in a close-fit, honed bore, the spindle was locked by a proper split-compression bush and fitted with a zeroing micrometer dial. Supplied with each new Primus was a complete set of electrical equipment - enabling the lathe to be run immediately upon delivery - Morse centres for headstock and tailstock, a headstock spindle reduction sleeve formed to take direct-fitting collets, a collet draw-tube, carriage stop, a set of seven screwcutting changewheels for the LD model, a pressure grease gun, spanners, five shear pins for the leadscrew drive and an operation manual. In an obvious attempt to compete with the Austrian-built Emco V10 and V11 lathes, one interesting accessory was a powered vertical milling/drilling head that bolted to the back of the bed. Closely resembling the Emco unit - but of higher quality with both the No. 2 Morse taper, 50 mm travel quill and main column hardened - that on the Weiler had a maximum distance between spindle nose and table of 350 mm and a throat of 210 mm. Further high-class engineering was to be found in the drive system, a flange-mounted, 0.37 kW 3-phase motor driving through oil-bath lubricated, planetary gearing that gave stepless speeds in two ranges: 85 to 540 r.p.m. and 335 to 2200 r.p.m..
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