Made from a hammered, high-tensile alloy-steel forging, the spindle rotated in large Timken Zero Precision Taper-Roller Bearings (of great expense) at the front and middle - and was allowed to "float" in a ball-race bearing at the rear. In this type of spindle mounting the front and centre bearings were "opposed" to absorb spindle thrusts in either direction - and so eliminate the necessity for a thrust bearing, or thrust washers. The centre bearing also helped by supplying a rigid support for the spindle midway between the front and rear bearings - and so reduced deflection under the heaviest cutting loads. Lubrication was provided by a pump that forced filtered oil directly to the bearings and, conducted to the right places by a network of pipes, sprayed it onto the transmission gears, starting clutch and brake mechanism. Cleverly, although the oil supply was carried in the base of the headstock, it was positioned beneath the gear line to prevent churning and heating of the oil at high speeds. Both flow and level indicators were provided on the front of the headstock. Fitted with the then popular "American Long Nose key-drive taper the spindle nose was an L1 size for the three ordinary models and an L2 for the 20-inch Heavy Duty. However, a "Cam-lock" type could be supplied, if preferred by the customer. The removal of a small plate at the rear of the headstock gave access to a convenient means for adjusting the bearings. With the plate off a shaft was exposed which, when rotated, actuated a worm and worm wheel that in turn moved an adjusting collar. One turn of the adjusting shaft, which was self-locking, supplied a 0.001" adjustment to the bearings. The ease with which this could be done led the makers to suggest that the lathe operator himself could be encouraged to keep his spindle bearings in proper adjustment - an idea that might have gained acceptance if the chap doing the job knew what he is about. Unfortunately, if Fred "The Monkey Wrench" Johnson, the factory know-all turned up, the result might not have been quite that intended. The direction of the carriage movement could be reversed, without stopping the lathe or having to reverse the direction of rotation of the feed rod, by a lever operating a double bevel within the apron. Operation of the headstock clutch and spindle brake could also be controlled from the apron - as well as from the headstock.
Fitted with heat-treated gears, the double-walled apron had all shafts supported at both ends. The handwheel-operated gears that drove against the bed rack all ran on roller races, a design that helped to give the massive carriage a particularly easy and free-running feel, especially when chasing threads and attempting delicate work with a hand-driven traverse. The control levers for power sliding and surfacing feeds were on American Monarch (and English CVA) lines, with a powerful spring engaging a cone clutch on the power sliding and what the makers described as a "Safety angular tooth" on the cross feed. Both could be disengaged instantly by the cam action of the control lever, even when fully stressed under very heavy cuts. Should the feeds have been overload, the friction clutch on the longitudinal feed eased the drive whilst the cross-feed mechanism was designed to automatically disengage. The apron internals (and the bed and cross-slide ways) were lubricated by a plunger-type pump, one stroke of which provided enough oil for a whole day's working.
Designed to provide a long and reliable life thee cross-feed screw was hardened, fitted with ball thrust bearings, had a nut of the "compensating" type, adjustable for wear and the elimination of backlash and was equipped with an automatic oiling system. The direct-reading micrometer dials were of a reasonably large size, made in stainless steel and fitted with adjustable friction collars. Both slide gib strips were of the full-length taper type. adjustable from both ends. A rarely-fitted sophistication on any make was the provision of a "micrometer ball threading stop" as standard equipment on all Pacemaker lathes. At the end of each threading pass, the tool could be instantly withdrawn clear of the job (by up to three revolutions of the cross-feed screw) and the carriage wound back to its starting point. The tool could then be reset to its precise, original depth, and any additional cut put on before the screwcutting restarted. The device was mounted directly above the apron traverse handwheel, on a raised rectangular boss, and functioned in both forward and reverse directions. It could also, very handily, be used for both external and internal chasing operations or employed as a positive, single-diameter stop for duplicating diameters.
Of entirely conventional design, and supplied with a convenient one-shot lubrication system operated by a plunger, the screwcutting gearbox could generate 48 standard threads on the ordinary models and 60 on the 20-inch HD - without having to dismount or add any gears to the quadrant arm. Extra gears were available to cut metric, diametral and modular pitches and two special sets available to generate pitched of finer and coarser pitch than standard. The one useful thread missing from all the charts was 19 t.p.i. Used only to generate threads, the leadscrew was driven by a gear on power shaft that could be slid into and out of mesh by a small lever positioned where the shafts entered the gearbox on its right-hand side. The direction of the carriage movement could be reversed by a lever, operating a double bevel within the apron, without stopping the lathe or having to reverse the direction of rotation of the feed rod. Especially useful on the long-bed versions, it was also possible to control the spindle clutch brake from the apron as well as from the headstock.
A superbly designed and executed taper attachment was offered either as a plain version, with hardened steel guideways, or as a ball-bearing, anti-friction type. The plain-bearing version was essentially the same sturdy design as the anti-friction type, except that the Meehanite slides operated on hardened and ground steel ways with full-length Meehanite taper gibs for quick and easy adjustment. The makers claimed that this combination of materials reduced friction to a level that was almost the same as that of the anti-friction type - in which case the extra expense of the latter would not seem to have been justified.
The Ball Bearing Type was equipped with twenty-four permanently sealed anti-friction bearings - which could be adjusted for wear. Hardened and ground steel surfaces or "ways" were supplied for the anti-friction bearings, both in the sliding shoe and the bottom slide. These surfaces were extremely hard and kept clean by Duprene wipers, whilst all exposed surfaces were fitted with neat dirt guards..