Atlas made metal-turning lathes, in various styles, from the early 1930s until the late 1970s but this page deals with the Company first model , the 9-inch, with links above to take you to descriptions and pictures of the later and more common  6-inch, 10-inch and 12-inch models. The world first lathe with an integrated, all-V-belt drive system, the original, lightly constructed 9-inch Atlas, with its "Compound V-belt Drive", was introduced in 1932 and also appeared in that year's printing of the Sears, Roebuck catalog as the Craftsman "Metalmaster". It continued to be sold (and improved in detail) until 1938 when its status had deteriorated to being advertised on the same page and under the same heading as the "Utility" model, a simplified machine based on the much-improved 10-inch model first offered in 1936. In addition to the Atlas and Metalmaster labels, examples have also come to light with a badge proclaiming "Metalcraft Lathe", another name used for machines marketed through the Sears mail-order business.
In the first catalog the lathe was not accorded a model number but, from the second and subsequent editions, the numbers 918, 924, 936, 942, 948 and 954 were used with the units and tens digits indicating the bed length that gave, respectively 18", 24", 36", 48" and 54" between centres.
Everything about the 9-Series' minimal appearance would seem to suggest that the management's instruction to the designer was, "Use the smallest amount of metal that allows a component to do its job" - and it is instructive to compare it to the later, more fully-developed and heavier 10-inch machines shown on other pages.  The lathe was not fitted with a backgear (unless specified as one of the cheaper "Unit Plan" machines) but used instead a "double-reduction" V-belt system running on a Hyatt roller-bearing countershaft unit bolted to the back of the headstock. The lathe's ingenious drive system was protected under a United States patent No. 1909522 in the name of James G. Collins - but assigned to the Atlas Press Company, by whom, presumably, he was employed. The application was filed on March 8th, 1932 and granted on the May 16th, 1933
The "integral" construction of lathe and countershaft was a strong selling point for no longer was there any need to find a location in the workshop where the new owner could spend the best part of a day struggling to install a wall or ceiling-mounted countershaft; this machine could be dropped onto a bench, plugged in and used within minutes of arriving home.
In the "high-speed" position the new drive system was entirely conventional; a small pulley on the motor drove a large pulley on the swing-head of the countershaft from which three direct-drive speeds, of 220, 370 and 600 rpm were transmitted to a matching 3-step pulley on the headstock spindle. To obtain the "Low-speed" range takes rather longer to explain than to set-up in practice. The countershaft-pulley shaft was formed in two concentric parts, the right-hand side carrying a large, single pulley that was driven separately from the headstock 3-step pulley by a small pulley fastened to its right-hand face. Normally the small right-hand countershaft pulley just idled, but a "shift collar", inboard of the left-hand countershaft bearing, could be moved to the right to bring it into action. When pushed to the right the collar unlocked itself from the shaft and two pins, which extended from its side, went completely through the 3-step pulley and entered the single pulley on its right-hand side - and locked the two together as a "floating unit". The eventual outcome of these manipulations was that the drive went from motor to countershaft, countershaft to headstock, back from headstock to countershaft then, using the 3-speed pulley, back to the headstock to give three slow speeds of 47, 80 and 130 rpm. Although the maker's instructions do not mention the point, some method of releasing the 3-step spindle pulley must also have been provided, otherwise it could not have acted as a drive transmitter. Scrutiny of the picture below should instantly make this interesting down-up-down 'modus-operandi' a little clearer. If you have one of these lathes, but no headstock-spindle drive belts, a good starting point is to try 30-inch belts on the two right-hand pulleys and a 31-inch on the left. The drive, although it eliminated costly backgears, cannot have been a success, probably for two reasons: it was, (and still is) surprisingly difficult to machine sets of pulleys, and purchase quantities of accurately-sized V belts, so that a multi-step drive works  without the need for some small adjustment in tension when the belt is moved from one speed to another. In addition, as the pulleys wear, the difficulty of setting the belts "just so" increases. On the Atlas this "variable" adjustment was partially achieved by allowing the countershaft head to be adjustable through the ingenious and simple self-aligning "floating" bearings housing with, of course, the whole head further adjustable for belt tension against an over-centre locking bar.
Almost all belt-drive systems, when heavily loaded, tend to slip and because the Atlas (for so light a machine) was capable holding rather large pieces of metal, the original design was almost certainly dropped because in "low-gear", if the cutting tool was applied to the edge of a 10" diameter piece of steel, the drive would have been hard pushed to cope with the loadings. A conventional backgear system was used on the later 10-inch lathes - and the problem solved.
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When the 10-inch lathe was introduced (the 9-inch continued in production) its motor pulley, and the corresponding countershaft pulley, were both of the two-step type, so doubling the number of speeds; this arrangement was immediately made available as an option on the 9-inch lathe - and raised its top speed to 2750 rpm. Atlas must have been convinced about the effectiveness of the very light "wavy-spoke" countershaft pulley (though they are often seen to wobble on well-used machines) for it was employed on the larger Atlas lathes until the very last (new-model) 12-inch versions made in the 1980s. Another feature was also to become a trade-mark tradition: the use of "Zamak", a combination of aluminium, magnesium, copper and zinc pressure injected into hardened-steel dies and used for gears, handwheels, pulleys, clasp nuts and other small items--though on the 9-inch it was used for the cross-slide casting and on the early 10-inch for the lower section of the top slide. "Zamak" (the name was a registered trade mark) was developed by the New Jersey Zinc Company and used from the beginning of Atlas lathe production until the end. Further details of this interesting material can be found on the Atlas 10-inch lathe page.
The hardened and ground No. 3 Morse taper spindle with an 8 U.S.F thread had a 0.75" bore and ran in "babbit" bearings, each held in place by a two-bolt cap packed up with shims that could be delaminated in 0.002" strips (just like a Myford ML7) to allow adjustment for wear. The headstock assembly, with the bearings sitting on top of unbraced columns, was typical of contemporary small-lathe practice and reference to the Series-10 illustrations will show how this part was greatly strengthened and improved on later models.
In place of a conventional headstock-mounted tumble reverse a "leadscrew-reverse gearbox", containing a bevel gear arrangement, was fitted at the headstock end of the leadscrew; this worked well, and enabled the carriage to be driven along the bed in both directions at the flick of a lever, however, it was unfortunately prone to damage by impatient, ham-fisted operators. No power cross feed was fitted on this, or the early 10-Series model.
Several "Utility" models were also introduced stripped of their more expensive components, and sold at a much reduced price (see below and here for early Utility models and here for later Utility models)
Beds with between-centre capacities of 18", 24", 30" and 36" were all available to order and, although this became a very popular lathe in the USA, no examples have yet been found in Europe.
A photographic essay on the early 9-inch and Metalcraft models can be seen here over 3 pages.

Atlas 9" Model 936 (36 inches between-centres capacity)
By 1936 the bed had been fitted with longer and more supportive feet, the saddle, apron cross and top slides strengthened and their castings given a distinctly rounded appearance. The tailstock resembled that fitted to the early 10" lathes whilst both the changewheel cover and motor switch were identical to those used on the contemporary 10-E lathe.

Unashamedly advertised as the "Utility" model bench lathe this rare 18-inches between centres machine, with a production run from around 1934 until 1938,  retained the screwcutting facility of the better-specified lathes but had only 6 spindle speeds (202, 330, 530, 610, 1015 and 1625 rpm) obtained by the use of a 3-step pulley on the headstock and a double step pulley on the motor to countershaft drive.
On the original "918" version not only was no backgear was fitted but also a simple, 'non-swivelling' cross slide was specified. Two other 918 models were available: the 918A, which came with a complete set of changewheels to cut threads from 4 to 96 t.p.i. and the 918B, which had, in addition, a graduated, swivelling compound slide rest. .

The well braced but lightly-constructed bed of the early 9-inch Atlas.