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Murad Antarctica Lathe
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Literature is available for Murad machine tools

Although Murad were well known in the 1940s and early 1950s for their small capstan lathes, and later for the unusual "Bormilathe" combination lathe and milling machine, only limited numbers of their ordinary centre lathes, the "Antarctica" and "Cadet", were made.
Replacing the expensive-to-produce geared-head Cadet, the second of  Murad's lathe was a high-quality, 4" x 21" backgeared and screwcutting machine with a straight (non-gap) V-bed and an all V-belt countershaft unit. Named the "Antarctica", after a specially-prepared example that had been supplied to the Shackleton Base of the British Antarctica Expedition. When the first production example left the factory during November, 1947, the range consisted of three models: "Alpha", "Beta" and "Gamma. The Alpha and Beta were both designed for bench mounting with the Beta benefiting from being supplied bolted to a heavy and very rigid, distortion-resistant "three-foot" cast-iron tray. The most desirable model, the "Gamma", was fitted as standard to a cast-iron pedestal stand.  All castings were poured in Murad's own foundry; the bed included 33% steel in the mix to give a "semi-steel"  (high-tensile cast iron) close-grained structure that was aged in the open for at least 9 months before machining and final hand scraping.
While all initial models had six spindle speeds, from 39 to 870 rpm, this was soon increased to 12 - by usual expedient of using a double-size pulley on the motor shaft together with a matching larger pulley on the countershaft. However, although the total number of speeds was the same, each model had its own speed range, arranged (on later types) as follows: 39 to 1300 rpm for the Alpha, 39 to 2000 rpm for the Beta and a very useful 39 to 2520 rpm for the Gamma. The countershaft, mounted integrally with the lathe and pivoted on an extension to the rear of the headstock-end bed foot, was fitted, like many other lathes, with a neat and highly effective "over-centre" adjustable belt-tensioning arm. The introduction of higher speeds coincided with a set of improvements to the headstock assembly designed to promote smoother and quieter running; these included: grinding and lapping  the spindle journals and hardening its mounting threads and Morse taper socket; individual and group balancing of all the rotating components and balanced and lapped backgears. It is also possible that the original spring-loaded plunger location for the backgear engaged and disengaged positions was replaced by a cheaper swing over lever with the gear held in place by a friction screw. With these modifications completed, one example that passed through the writer's hands ran with commendable smoothness and in almost complete silence. The headstock spindle bearings were unusual; realising that the recently introduced (American-designed) steel-backed white-metal lined "Thinwall" shells for the main and big end bearings of IC engines were items of very high precision, Murad engineers decided it would be a useful short cut to use those instead of more traditional components: cast-in white metal, bronze, ball-bearing or taper roller races. Taking advantage of the shell-bearing manufacturing facility that the factory had installed as part of the development program for the Murad car these bearings were duly installed in the lathes; once fitted they were line-bored and, despite being fed lubricant from wicks dipping into wells within the headstock casting (instead of being supplied with high-pressure oil) appear to have been a success - certainly the very well-worn lathe examined by the author in the early 1980s still had a perfectly serviceable spindle assembly. Whilst the two bench lathes had a very heavy combined motor-countershaft unit fastened to the back of their bed the Gamma had its motor bolted to the rear of the cabinet stand. The headstock belt run on all models was guarded  with a large rear-hinged cast-aluminium cover. The electrical switch was conveniently mounted on a boss of rather exaggerated proportions that was formed as part of the headstock casting's front face.
Although all three lathes were of identical mechanical construction, because of their more rigid mountings (which owners would have found difficult to upset) Murad offered the Beta and Gamma with accuracy test certificates - the assembly technique with both machines being to do the final fitting and set up after the bed had been bolted to its tray or stand.
Screwcutting was by fully-guarded changewheels (there was no gearbox option) of which the unusually large standard set of twenty-two gears set was able to generate threads from 2.5 to 95 t.p.i. The tumble-reverse mechanism was unusual in being mounted behind the spindle with the spring-loaded operating lever positioned vertically above and to the left of the end headstock bearing.
Double-walled, the apron was attached to a generously-long saddle with both heavily constructed (and increased in size on later models); all shafts in the apron were supported in double bearings and its hand-feed action was driven through triple reduction gears running in an oil bath. The top and cross slide feed screws were of Acme form and carried spring-loaded zeroing micrometer dials. The leadscrew clasp nuts were in bronze and carried in adjustable dovetail guides whilst the dial-thread indicator was built into the apron and engaged by an ingenious eccentric mechanism actuated by a knurled ring.
Of especially robust construction, with a very long sole plate, the early models of tailstock were spoiled by the use of a simple split in the casting closed down by a (substantial) handle to lock the barrel. This arrangement can, unless made to very close limits, be frustratingly difficult to use - and with any wear resulting in the need for enormous pressure to make it work. Fortunately the Murad example was particularly well made, with close-fitting components, and owners report that only the slightest pressure was required to achieve a very firm lock. Later machines were improved, first with a compression fitting with upper and lower halves of a split bar closed down by a screw, and then by the use of a redesigned and even more substantial casting. Unfortunately on both types a loose "self-hiding" spanner was need to clamp the unit to the bed - a requirement that would have guaranteed endless wasted time whilst the operator looked for it.
Although the lathe supplied to the Ataractic Expedition was not greatly modified, it was supplied with a complete range of accessories (except a taper-turning unit) and the stand, instead of being in cast iron, was constructed from steel fabrications topped with an aluminium tray to reduce the considerable all-up weight of the standard machine.  Owners of standard production models lathes report that they were especially well finished, in a dark-green paint..

Murad Antarctica "Alpha" Precision 4" x 21" circa 1947

Murad Antarctica "Gamma" Precision 4" x 21" of the early 1950s on a cast-iron cabinet stand.

The Murad Antarctica "Beta" benefited from the effect of being bolted to a heavy and very rigid, distortion-resistant "three-foot" cast-iron tray. 

End view of the Antarctica showing the unusual position of the tumble reverse mechanism.

Component parts of the headstock assembly

The Alpha and Beta were both designed for bench mounting, but with the lstter benefiting from the effect of being bolted to a heavy, very rigid, distortion-resistant "three-foot" cast-iron tray.

This early example of the Murad Antarctica lathe has six spindle speeds from 39 to 870 rpm. This was later increased to 12 by usual expedient of using a double-size pulley on the motor shaft together with matching larger pulleys on the countershaft; each model had its own speed range, arranged (on later models) as follows: 39 to 1300 rpm for the Alpha, 39 to 2000 rpm for the Beta and a very useful 39 to 2520 rpm for the Gamma.

The double-wall apron and generously-long saddle were both heavily constructed (and increased in size on later models); all shafts in the apron were supported in double bearings and the hand-feed action driven through triple reduction gears running in an oil bath. The top and cross slide feed screws were of Acme form and carried spring-loaded zeroing micrometer dials.

The cross-feed screw was arranged to that its slide could be brought well forward of the apron's front face

Screwcutting was by fully-guarded changewheels (there was no gearbox option) of which the unusually large standard set of 22 gears set was able to generate threads from 2.5 to 95 t.p.i. The tumble-reverse mechanism was unusual in being mounted behind the spindle with the spring-loaded operating lever positioned vertically above and to the left of the end headstock bearing.

The countershaft, mounted integrally with the lathe and pivoted on an extension to the rear of the headstock-end bed foot, was fitted (like many other lathes) with a neat and highly effective "over-centre" adjustable belt-tensioning arm. This example is an early model, with six speeds, but on later machines this was increased to 12 by usual expedient of using a double-size pulley on the motor shaft together with matching larger pulleys on the countershaft; each model had its own speed range, arranged (on later models) as follows: 39 to 1300 rpm for the Alpha, 39 to 2000 rpm for the Beta and a very useful 39 to 2520 rpm for the Gamma.

Catalogue illustration of the countershaft - but omitting the over-centre tensioning lever. Note the backgear engagement lever: instead of a spring-loaded plunger to locate the engaged and disengaged positions a cheaper swing-over type, held by a friction screw, was used on the example.

Catalogue picture of the actual lathe sent to Antarctica.

The later and rather different tailstock from a Murad Beta

email: tony@lathes.co.uk
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Murad Antarctica Lathe
Murad Home Page   Murad Antarctica Lathe   Murad CADET   
Murad Capstan   Bronson Motor  Memories of Murad   
Murad Factory   Murad Car   Other Products

Literature is available for Murad machine tools