Introduced in 1932, at $64.50, the original, lightly constructed 9-inch Craftsman "Metalcraft" lathe was really an early Atlas product - and virtually identical to that Company's own machine of the same capacity. Although "V" belts had been widely available from the early years of the 20th century they were in the form of a wide and clumsy sectional type (identical in concept to today's "T-Link" type) and often used on the final-drive system of less-expensive motorcycles (where their "soft" action took some of the roughness out of the crude power delivery then common). However, just post WW1, a revolution in transmission design was created when the first continuous-loop, narrow-section  "wedge" belt was introduced - though it was to be nearly ten years before it became widely adopted. Atlas lead the way in its application to a small lathe when, in 1932, they introduced an entirely new model, the world's first small lathe with an integral all-V-belt drive system. With motor and countershaft attached to the back of the machine, there was no longer any need for the new owner to find a location in the workshop where he 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. Described as having a Compound V-belt Drive the lathe was of light construction, with a 9-inch swing (4.5-inch centre height) and also appeared in that year's printing of the Sears, Roebuck catalog as the Craftsman Metalcraft as well as being badged Partner - with both versions painted bright blue (it was also sold, rather confusingly, as the Metalmaster). Appearing only on those lathes with the cheap tin-plate changewheel guard, the Metalmaster and Partner badges were printed on the electrical cover - the inside of which contained, reflecting the true economy of the lathe, a standard-for-the-period household light switch…...
Continuing in production until as late as 1938 (with a number of modifications) the status of the model slowly declined until it was being advertised on the same page and under the same heading as the Utility model - the latter a simplified machine based on the much-improved 10-inch model first offered in 1936. 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 denoting the bed lengths that gave, respectively 18", 24", 36", 48" and 54" between centres.
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Although a revolutionary machine in so many ways, everything about the 9-Series minimal appearance would seem to suggest that the management's direction to the designer was, "Use the smallest amount of metal that allows a component to do its job so that we have the maximum profit per unit" - and it is instructive to compare it to the later, more fully-developed, heavier and rigid 10-inch and 12-inch machines shown on other pages.  The lathe was not fitted with backgear (unless, in later years, specified with a simplified drive as one of the cheaper Unit Plan machines) but instead used a "double-reduction" V-belt system running on a Hyatt needle-roller bearing countershaft unit bolted to the back of the headstock. The needle roller where held in cast-iron cases adjustable for alignment by a simple but ingenious system using opposed screws. Later models of the lathe, from 1935 onwards, had the expensive bearings replaced by simple Oilite bushes. These widely-used and still very common bearings must be lubricated with oil, not grease, as the Oilite material is a form of sintered bronze and saturated with oil during manufacture. As the shaft turns the assembly warms up and the oil becomes free to lubricate the shaft. After use, and the bearing cools and the oil is partially reabsorbed; although intended to be maintenance-free, it is necessary to apply a little light oil occasionally to replace that lost through evaporation where it seeps from the (usually) unsealed bearing ends.  The lathe's original and ingenious countershaft drive 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.
In its "high-speed" position the Collins drive 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 moved 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 so locked the two together as a "floating unit". The eventual outcome of these various manipulations was that the drive went from motor to countershaft, countershaft to headstock, back from headstock to countershaft and 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: with just belt drive it's difficult to get a, effective  really low gear ratio (and the slower the belts run the greater their tendency to slip) and 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 some compensation for differences in belt length could be partially made by adjusting the setting of the countershaft bearings in their simple but ingenious "floating" housings with, of course, the whole head further adjustable for belt tension against an over-centre locking bar.
Because the Atlas was (for so light a machine), capable holding rather large pieces of metal, Collins's original idea of low speeds being provided entirely through belts was almost certainly dropped because, in "low-gear", when the cutting tool was applied to the edge of a 10" diameter piece of steel, the drive was - to put it kindly - hard pushed to cope. A conventional backgear system was used on the later 10-inch lathes - and the problem solved.
Hardened and ground, the No. 3 Morse taper spindle had an 8 U.S.F thread, a 0.75" bore and ran in "Babbit" bearings, each with a cap packed up on 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; reference to the pictures below will illustrate how this part was greatly improved on later models.
To reverse the direction of the automatic carriage drive a "leadscrew-reverse gearbox", containing a bevel-gear arrangement was bolted to the bed at the headstock-end of the lathe. This device worked well, but unfortunately was prone to damage by impatient, ham-fisted operators. Although Atlas retained this gearbox on machines marketed under their own name until the revised lathes of 1959, on Craftsman branded models from around mid 1936 it was replaced by an ordinary and very effective "tumble-reverse" mechanism. The first version used a simple (and slow to operate) bolt-to-secure lever (exactly like the South Bend 9-inch) while later models had a more convenient type with a spring-plunger that obviated the need to find a hunt down the right wrench. The 6-inch and Mk. 1 (pre-1958) 12-inch lathes both used ordinary changewheels on the tumbler assembly, a 20t on the front stud, a 24t at the rear and a 16/32 compound gear beneath on the output stud..
No power cross feed was fitted on this, or early versions of the 12" model that replaced it; indeed, the first models had their saddle and apron cast as one, with short bracing flanges supporting an extension of the saddle that formed the front part of the cross-slide ways. Of particularly light construction, the cross-slide was cast in Zamak, a material not ideal for resisting torsional stresses. As some disgruntled owners discovered, bolting down the top slide could twist the assembly and stiffen the cross-slide action. On a positive note, a choice of beds was offered having between-centre capacities of 18", 24", 30" and 36".
From 1936, and the introduction of the "conventional" tumble-reverse  12" machine, the lathe developed steadily and became both more robust and reliable as various components were redesigned or improved; the new model was available in both 8 and 16 speed versions (the latter by simply fitting a two-step pulley to motor and countershaft) and both with and without backgear. The least expensive lathe on its introduction was catalogued as the 8-speed, 18 inches between centres, non-backgeared Model "99 PM 2028" at $63.50 whilst the most expensive was the "99 PM 2030" with a capacity between centres of 36 inches and a price of $93.95. Models with 18, 24, 30 and 36 inches between centres were available. Without backgear the speed range was: 170, 270, 430, 504, 680, 832, 1298 and 2100 rpm; with backgear the range became a much more useful: 32, 50, 74, 88, 120, 142, 170, 210, 270, 350, 430, 504, 680, 832, 1298 and 2100 rpm. In 1939 power cross feed became available on the De-lux models and, in 1941, sixteen speeds were made standard across the range with a corresponding increase in price to $89.50 for the cheapest version. Prices continued to rise steeply as war-time conditions took over: in 1942 the range spanned $105 to $165 and in 1943, the last year that the Craftsman power Tools catalog was to appear until 1948, $125 to $179.50 - an effective doubling in ten years of production.
When Craftsman lathes became available to the civilian market again in 1948 (and in line with a similarly restricted model range from Atlas), just two versions were available, both with headstock roller bearings and full belt guarding as standard: the "99 TM 2075 had a capacity of 24 inches between centres and was priced at $197 while the 36" between-centres "99 TM 2079" was listed at $212. 
Although in 1947 Atlas offered a screwcutting gearbox on their 10F model, it was not until 1951 that the Craftsman version was so equipped. The box appears to have been manufactured in several versions: the first was intended for retrofitting to existing lathes (Type 101.07403 and earlier models) with the original, thinner 3/8"  bed ways; the second was adapted to fit the 1/2"-thick way machines and the third, equipped with a safety-overload slip clutch, possibly introduced on the heavily revised lathe (sometimes carrying a "Commercial" badge) of 1959 - though a later date in the 1960s has also been suggested.
Numbers used on the identification plates for the 12-inch Craftsman lathe varied according to many factors, these including the bed length and type of motor fitted (with some machines having an extra zero on the end. The following sample selection including early types often marked: 101.27580, 101.27590, 101.28930, 101.28940, 101.28950, 101.28970 and later versions with, amongst other designations: 101.20140, 101.20280, 101.20300, 101.20320, 101.20650, 101.20670, 101.20690, 101,20710, 101.20730, 101.20750, 101.20770, 101.20790, 101.27440, 101.27430, 101.07301, 101.07303, 101.07360, 101.07361, 101.07362, 101.07363, 101.07380, 101.07381, 101.07382, 101.07383, 101.07400, 101.07401, 101.07402, 101.07403, M2075,  M2743,  M2079 and  M2744. etc. The different numbers referred to various combinations of bed length, motor type, etc.
If you have a 12-inch Craftsman with other numbers or identifications, the writer would be very interested to hear from you.

1932 Craftsman Metalmaster 9" x 18" 6 speed centre lathe with its revolutionary Collins all-V-belt integral countershaft system. In its basic form the lathe lacked both an electric motor and a compound slide rest (that was a additional $13 to the $64.50 cost of the basic lathe) - but it did have a full set of screwcutting changewheels, faceplate, drive dog, a (very cheap) household-grade electrical switch, a dial-thread indicator, two cutting tools and a motor pulley.
If the badges have disappeared from a lathe, the manufacturer's version, the Atlas 9", can always be identified by its different bed feet which, instead of the open cast boxes shown above, flared outwards in a smooth curve. Oddly, the Atlas patent drawing showed the Metalmaster feet.

The first of the new-style Craftsman 12-inch lathes as sold from late 1935 until, with several detail modifications, late 1936. This is a 16-speed, 24 inches between-centres model catalog Number "99 PM 2030". Based on a design first used for the 1935 Craftsman wood-turning lathe - which itself was a simplified version of the 1934 Atlas metal-turning lathe - from the very first model the swing was set at 12 inches (12.25" actual), some two inches more than the Atlas version that only achieved same size in the late 1950s when the long-lived 10F was heavily modified and re-introduced as the "12-inch". The saddle and apron were cast as one with short bracing flanges (just visible in the picture) supporting an extension of the saddle that formed the front part of the cross-slide ways. In order to get the cutting tool up to the increased centre height the base and upper casting of the top slide was considerably increased in thickness in comparison with the Atlas version - the difference being especially noticeable in the picture above and an easily-recognised feature of all Craftsman 12-inch lathes until 1958. Note the very light tailstock, an item soon to be greatly improved.
When identification badges have disappeared from the lathe, to make an easy distinction between this and the equivalent Atlas model look for the lack of a bed-mounted leadscrew reversing gearbox - this being replaced by a conventional tumble-reverse mechanism; details of this are shown below.
This version - and all subsequent models -  of the Craftsman 12-inch lathe had the expensive, grease-lubricated, needle-roller bearings of the countershaft replaced by simple Oilite bushes. These widely-used and still very common bearings must be lubricated with oil, not grease, as the Oilite material is a form of sintered bronze and saturated with oil during manufacture. As the shaft turns the assembly warms up and the oil becomes free to lubricate the shaft. After use, and the bearing cools and the oil is partially reabsorbed; although intended to be maintenance-free, it is necessary to apply a little light oil occasionally to replace that lost through evaporation where it seeps from the (usually) unsealed bearing ends. 

Mid 1936 A very rare "interim" Craftsman 12" that combined a number of early and late features: the much-improved and thicker saddle (necessary to get the cutting tool up to height yet still with a thick upper casting of the top slide) the very first type of (bolt-retained) tumble-reverse mechanism on the changewheel drive - and the continuing, use of the early-pattern light tailstock.
Photographic essay here

Sears were right to insist upon the use (for the Craftsman branded lathes) of a tumble-reverse mechanism in place of the awkward-to-operate leadscrew revering gearbox on the Atlas. The first attempt, shown here, required a spanner to operate and was quickly superseded (in a matter of months) by one with a quick-to-operate, spring-plunger lock.

Craftsman 12" lathe 16-speed Standard as produced from late 1936 until late 1937
By 1936 the lathe had undergone many detailed changes and become, like the equivalent Model "D" Atlas, a very much more robust and useful machine. The model illustrated above could have been marked Model 101.07400 or, if towards the end of the production run, 101-L6A 3473S (still with Catalog Number 99 PM 2030) and was the basic 16-speed unit (with backgear) and fitted with babbit plain headstock bearings, a partial guard over the headstock belt and no cover on the motor to countershaft drive - though these refinements were available from the options' list. It retailed from $69.95 to $100 compared to $99.50 to $125 for the De-lux specification (probably marked 101.07403) a lathe that included Timken taper roller bearings in the headstock and, in most years of production,  more comprehensive guarding of the drive belts. Although the (relatively short) bed feet remained unchanged the tailstock was completely redesigned and made immeasurably stronger (this first type is recognisable by the absence of a dipper-rod holder on the front of the casting) and the tumble-reverse lever fitted with a spring-plunger for location. Unfortunately the catalog pictures of the era are not completely correct and suffer from artistic meddling - for example, the Standard machine illustrated above has the roller bearing headstock that was available only on the De-lux model. Owners of these 1936/37 lathes report that a mixture of castings was still used marked, variously "9-" and "10-", reflecting the gradual evolution of the model from the original 9-inch version (though Craftsman-badged versions of course made the jump to a 12-inch rather than 10-inch swing of the Atlas).

Craftsman 12" lathe 16-speed De-lux as introduced in late 1937 and manufactured until late 1939.
The De-lux had not only "selected" Timken taper roller headstock bearings, but comprehensive guarding of both countershaft and headstock belt runs. For the first time the bed feet were extended to support two-thirds of its length and the tumble-reverse mechanism (which reversed the direction of the leadscrew) fitted with a spring-plunger instead of the bolt arrangement.. Prices now ranged from $77.50 for the very basic 8-speed, non-backgeared "99 PM 2028" with 18 inches between centres to $139 for the De-lux Model "99 PM 2032" with a 36 inch capacity. The standard version, as usual, economised with plain babbit (white metal) spindle bearings.

Craftsman 12" lathe 16-speed Standard as introduced in late 1939 and manufactured throughout the Second World War in virtually unchanged form (again, the maker's picture is incorrect--the lathe used in the publicity material has a roller-bearing instead of plain headstock and a front headstock belt cover instead of an open drive. The tailstock was further improved by the fitting of an oil reservoir (in those days it would have held poisonous "white lead") with a dipper rod to lubricate the back centre. Note the longer bearing, held in a more robust housing, at the tailstock end of the leadscrew. In 1941 16 speeds were made standard across the range with a corresponding increase in price to $89.50 for the cheapest version. Prices continued to rise steeply as war-time conditions took over: in 1942 the range spanned $105 to $165 and in 1943, the last year that the Craftsman Power Tools Catalog was to appear until 1948,  $125 to $179.50 - an effective doubling over the 10 years of production.
Note again the enormous depth of the top-slide casting still required to get the tool up to centre height.

A correct 12-inch Craftsman Standard of circa 1939/40 onwards. Unguarded headstock spindle drive belt, plain headstock bearings and, in this case, probably a slightly earlier design of tailstock. This lathe's specification tag reads: 101.07381

The first of the 12-inch lathes to have power cross feed were the 1939 De-lux 16-speed, Timken headstock bearing models. For the 1940 selling season -and anticipating larger increases to come -prices had rose slightly to span $79.95 to $155.

A useful range of 16 spindle speeds was available from the all-V-belt drive system with a double-step motor to countershaft pulley and a 4-speed headstock pulley.
It might be imagined that if a Craftsman lathe was going to be fitted with a roller bearing headstock the simplest and cheapest solution would have been for the Atlas to have supplied machines fitted with a headstock as close as possible in design to that used on their own 10-inch lathe or, at a pinch, take a standard headstock and modify it to carry bolt-on bearing caps. In this case however, not only was the design of the headstock casting and  belt-guard supports different, but the backgear assembly was bolted to the back of the headstock - presumably (though this was not mentioned in the catalogs) to allow the lathe to be offered at a lower cost if not so fitted..

Instead of the usual quickly-adjustable, over-centre headstock belt tensioning mechanism the Craftsman made do with a very simple lever arrangement retained in place by vertical plate which engaged between or in front of two collars on the tensioning rod. A similar system was also used on a rare version of the Atlas/Craftsman 6-inch lathe but with the operating rod (tipped by a metal knob) protruding through the front face of the headstock.

This picture makes clear the contrast between the more robust arrangements used on the Atlas version - where the headstock casting was extended rearwards to carry the backgear, and the cover pivoted off ears at the very back of the assembly..