email: tony@lathes.co.uk
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Mars Lathes - Australia
- also branded as the Conrick, Great Scot and Nextek -

Junior Lathe    Jupiter Lathe    Venus Lathe    Atlas Lathe   Mercury Lathe

A Mars full-range catalogue is available


Mars Lathe were made by the Mars Machine Tool Manufacturing Co. Pty. Ltd. of Bridge Street, FortitudeValley, Brisbane, Australia a company originally known as Rapson and Dutton. The firm produced a wide range of machine tools and other products including millers, shapers, planing machines, radial-arm drills, boring mills, hoists, bandsaws and even such items as diverse as paper guillotines and diesel engines. In advertisements they described themselves as ''Marine, Diesel and Aircraft Engineers'' and claimed expertise in the ability to design and manufacture ''Special Machines for all Industries''.  One advertisement even boasted: "The widest range of machine tools in the Southern Hemisphere". As with many other company's, various brand names were used to market their products including, in the case of their 5-inch lathe, "Conrik" and "Great Scot" One machine, a shaper, was known to have been named after a particularly skilled mechanic/fitter, Tom DuBoise, who was with the company from 1932 until 1964, while another long-serving member of the workforce was Vic Marsh; he joined the organization in 1924 and retired in 1964, having spent most of his time as the senior machine-shop supervisor. One of the lathe and other machine-tool designers was Bart Bulwinkel who worked in the drawing office during World War Two when, faced with a Japanese invasion, the factory was running three shifts a day and working flat out to meet the urgent demand for machine tools from the Australian armed services.
Being so catholic in their enterprises, it is likely that lathes played only a secondary role in the company's product range for, today, examples are rarely seen - and very little publicly literature seems to have survived. However, details of six models are available; the
JuniorVenus, Jupiter, Mercury, Atlas and the 'Hercules' 5.5-inch and the 'Mars 6-inch' - the latter two both very close in capacity yet quite different in the details of their construction:
The 5.5 inch centre height by 24-inches between centres 'Hercules' was described by its makers as the '
Little Giant of the Lathe World. Like the English Raglan 'Little John', it was heavily constructed, with a genuinely-useful specification for its capacity and not just a small lathe with headstock and tailstock 'built up in the sand' to stretch the capacity of a lighter, cheaper machine. The 49-inch  long V-way bed was ground-finished to within 0.00025'', had diagonal braces between front and rear ways and was fitted as standard with a 7-inch long detachable gap section - this increasing the capacity on the faceplate from 11 to 16 inches in diameter. At its headstock end the bed dipped down below the gap to form a mounting foot that bolted to a cast-iron plinth with a single (rather small) storage cabinet. Because the bed foot beneath the headstock was rather short it left a sizeable proportion of the casting, on the outboard end, cantilevered away from solid support. A generously proportioned and usefully-deep sheet-steel chip tray was fitted as part of the standard equipment.
Running in parallel-bore bronze bearings that could be adjusted by being drawn into their tapered housings, the high-tensile steel headstock spindle was bored through 0.75-inch, had a No. 3 Morse taper nose and axial thrust was taken against a ball race. Interestingly, the makers claimed that: ''
All Headstock parts are Dynamically Balanced to ensure vibrationless running at all speeds''. However, whether the same thoughtful precautions were taken with regard to the unguarded countershaft assembly, neatly built onto the back of the bed behind the headstock, is unknown. A V-belt took the drive from motor to the 3-step upper pulley with a flat-belt making the final connection to the headstock spindle. Making a profit on the sale of electric motors cannot have to appealed to the company's accountants for customers were expected to provide their own, the makers recommending a 1400 rpm, 1-hp unit that, in conjunction with a conventional 6 : 1-ratio  backgear, gave a speed range from approximately 45  to 850 rpm.
Drive by changewheels from the headstock to leadscrew was through a tumble-reverse mechanism and, with the standard set of hobbed gears, a limited range of pitches ( 8, 9, 10, 11, 12, 13, 14, 16, 18, 19, 20, 24, 28, 32, 36 and 40 t.p.i) could be cut. To obtain an especially fine feed, generate metric or other special pitches, gears with 63, 73 and 100 teeth were available at extra cost.
A separate 'powershaft' was connected to the left-hand end of the leadscrew by a permanently-engaged gear; the shaft drove the sliding and surfacing feeds in the apron through the usual worm-and-wheel arrangement with selection and engagement by a single lever that could be lifted into one of two slots. The design of the safety-interlock mechanism (that presented simultaneous engagement of power feeds and screwcutting) was unusual: instead of being hidden away behind the apron's front wall it was fitted to the outside where, one must assume, it must have proved a tempting device for apprentices to mess with or even remove - with potentially disastrous consequences. On the left-hand face of the apron was a swiveling casting, almost identical to that on the Mk. 1 Colchester Student, that acted both as a swarf guard for the leadscrew and a mounting point for the dial thread indicator.
Continued below:


5.5 inch centre height by 24-inches between centres Mars 'Hercules'



Mars 5.5-inch
The saddle was provided with two T sots, one at each side of the cross slide, into which the travelling steady could be fitted. Both cross and top slides were equipped with micrometer dials that were far too small for all but very young eyes; happily, a large-capacity 4-way toolpost, capped by a forest of clamping bolts, went some way towards compensating for this by being included in the original equipment.
The self-ejecting tailstock barrel had a No. 2 Morse taper barrel with a proper compression lock and the upper section of the main casting could be offset on the sole plate for taper turning. Although the illustration of the ''Hercules'' shows the tailstock apparently locked to the bed by stud and nut at the front of the casting these items were used to set the clamp's adjustment with the real operating lever protruding through the end face of the sole plate (this arrangement is clearer in the picture of the 6-model). Alignment of the tailstock was set to within 0.00025'' by the use of a 24'' test bar set between centres.
Besides those items already mentioned the following were also supplied as part of the standard equipment: faceplate; 3-point fixed and 2-point travelling steadies (both with neat screw-driven finger adjusters); a headstock adaptor sleeve; two centres and the drive belts. The length of the lathe is not known but it was listed as being 2'  9'' wide, 4' high and weighed a respectable (for its capacity), 934 lbs.


Mars 6-inch
The ''6-inch'' Mars lathe was of very similar layout to the 5.5-inch ''Hercules'' with a V bed, rear-mounted countershaft and a plinth and leg stand. However, whilst it offered very little in the way of extra swing (and at 25'' between centres, 3'' less in length) it was of a generally more massive construction and designed for heavier-duty tasks. All the rotating parts of the headstock assembly were dynamically balanced and the spindle, which carried a 3-step pulley with 1.5-inch wide flats to run a 13/8'' belt, was bored through 1.25''. Although the makers claimed that a result of the care taken to balance the headstock rotating parts was an ability to run smoothly up to 2000 rpm, the normal direct-drive speeds were 690, 946 and 1280 rpm whilst the conventional backgear gave a reduction ratio of 5:1 that added three slower speeds of 224, 169 and 128 rpm - the slowest of which was around twice as fast as the ideal for screwcutting and turning very large jobs on the (dynamically-balanced) faceplate.
Tumble reverse, exposed on the left-hand face of the headstock, provided a reversible drive to the standard-fit screwcutting gearbox. With the standard changewheel set in place the box could generate the following range of inch pitches: 6. 5, 7, 8, 9, 9.5, 10, 11, 12, 13, 14, 16, 18, 19, 20, 22 and 24.
Drive to the apron was through either a leadscrew or a permanently-engaged powershaft, the latter selectable by pulling out a knob on the gearbox. The apron retained the same design of worm-and-wheel-driven power-feed mechanism but the method of selecting and engaging the feeds was completely different to that on the 5.5-inch lathe with a single lever, positioned on the lower central section of the front face, moving through a 180 degree quadrant with a neutral position in the centre.
If any reader has a Mars lathe, or other Mars machine tools, the writer would be interested to hear from you..

The Mars stand at an Australian machine-tool exhibition during the 1950s


Junior Lathe    Jupiter Lathe    Venus Lathe    Atlas Lathe   Mercury Lathe

A Mars full-range catalogue is available

Mars Lathes - Australia
- also branded as the Conrick, Great Scot and Nextek -


email: tony@lathes.co.uk
Home   Machine Tool Archive   Machine-tools Sale & Wanted
Machine Tool Manuals   Catalogues   Belts   Books  Accessories