Home    Machine Tool Illustrations    Small lathes for Sale    Large lathes for Sale   
Shapers, Millers & Grinders for Sale
E-MAIL   Tony@lathes.co.uk   

"American" Pacemaker Lathes
Carriage Assembly
Headstock    Speed Change    Gearbox    Carriage    Taper Turning    Bed & Slides    Blueprints

The carriage on the Pacemakers was fitted with hardened wiper plates, honed to fit the "ways" and so ensure that swarf was completely removed. The assembly ran on two Vees with an adjustable gib strip underneath the rearmost slide - and keeper plates at the front.
The cross-feed screw was hardened and fitted with ball thrust bearings. The nut was fitted with an automatic oiler and was of the "compensating" type, adjustable for wear and the elimination of backlash. The direct-reading micrometer dials were of a reasonably large size, made in stainless steel and fitted with adjustable friction collars.
The compound slide gibs were of the full-length taper type.

The apron was fitted with heat-treated gears with their studs supported at both ends. The handwheel-operated gears which drove against the bed rack all ran on roller races which gave the carriage an easier feel, especially when chasing threads and attempting delicate work with a hand traverse.
The control levers for the power sliding and surfacing feeds were on Monarch and 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 heavy cuts. If the feeds became overload, a safety device of the friction type eased the power sliding, whilst the cross-feed mechanism would automatically disengage itself.
The whole apron was lubricated by a plunger-type "one-shot" system which provided enough oil for a whole day's working. A boss on the right-hand edge of the apron carried a lever which operated the headstock clutch and spindle brake - an ideal arrangement when the operator's position took him towards the tailstock of the lathe. 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.

To help with threading operations a "micrometer ball threading stop" was provided as standard on all Pacemaker Lathes.
At the end of each pass along the thread being cut, 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 started again. The device was mounted directly above the apron traverse handwheel on a raised rectangular boss.
The stop functioned in both forward and reverse directions, and could also be used for both external and internal chasing operations. A further use was to employ it as a positive single-diameter stop for duplicating - diameters..

Home    Machine Tool Illustrations    Small lathes for Sale    Large lathes for Sale   
Shapers, Millers & Grinders for Sale

E-MAIL   Tony@lathes.co.uk   

"American" Pacemaker
Carriage Assembly
Headstock    Speed Change    Gearbox    Carriage    Taper Turning    Bed & Slides    Blueprints