The cheapest early Myford was the 31/8" x 15"  ML1 with bed and headstock cast as one. This art-worked picture, though used in a 1938 catalogue , shows the lathe as sold from early 1935 with single-bolt retained top-slide, cast-in headstock-end leadscrew bearing and the very early tailstock side plate without adjuster screws.
Note the extra changewheel protruding above the centre line of the headstock. This was fitted to a forked bracket and allowed left-hand threads to be generated

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Like many contemporary small lathes the guarding of belts and gears was either rudimentary or non-existent. However, by the late 1930 several designs of changewheel cover appeared, obviously in search of a simple but economical solution and at first were offered as an option - 7/6d buying the first type, a rather crude hinge-up affair that lacked an inner cover. This was replaced by an assembly that used a cast-iron plate bolted to the end of the bed, with the cover located by a dowel at the back and a knurled thumb screw at the front (just like the ML7) and finally, but very rarely found, a cover (together with an inner plate) that hinged open in the manner of that fitted to the Super 7. 
Although the later division of the range into Standard and Superior models brought a choice of a spindle running directly in the cast iron of the headstock (an excellent situation if the spindle is hard and carefully finished) or bronze bearings, the early (very rare) catalogues failed to mention that for 10 shillings extra (in 1937) this option was also available then. However, one owner of a new ML.4, purchased in 1937, reported to the writer that, because he found the headstock bearing housings to be roughly finished, alignment had to be obtained by pressing the bushes in and then boring them true. Whilst this method might have been an excellent expedient to quick and easy production it did nothing for the owner who subsequently wished to replace the bearings - just fitting new bushes resulted in hopeless misalignment of the spindle. The bearing housings were "split" on one side and with a pinch bolt to provide a form of initial adjustment and care must be taken not to over-tighten the clamping screws as the assembly wears - it is very easy to snap the headstock casting and an effective repair is both difficult and expensive. If the "split" bearings on your early Myford (or other small lathe) are worn, it is much better to bite the bullet and have the spindle hard chromed, ground to size and a new pair of bearing made up and carefully bored true by your local precision engineer.
In the 1930s, when money was tight, many lathes were sold without countershafts, the owners preferring to construct their own from handy scrap. If you were lucky enough to be able to afford the real thing Myford offered two basic units for bench mounting: a simple, non-adjustable affair and a rather superior one, not dissimilar to that offered for the 6-inch Atlas in the USA. The better countershaft resembled a tall angle plate, slotted for motor mounting and with a hinged top holding bearings secured by pairs of opposing screws that allowed then to become "self-aligning". 
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A very late Myford ML.2 with the headstock and left-hand leadscrew support bracket both bolted on. The top slide had a bolt at the front as well as the back, tumble reverse was fitted as were graduated dials on the compound slide-rest feed screws. The changewheels were completely enclosed by a bolt-on cover with backplate. In this publicity picture the tailstock has been art-worked to resemble the later, much-improved type.

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Every ML.1, ML.2, ML.3 and ML.4 had a carriage of similar construction with a simple, lightweight apron secured to the saddle by two slotted-head screws and a direct rack-and-pinion drive from a balanced handwheel - a small movement of the handle producing a disproportionately long travel of the cutting tool. To solve this problem the makers offered a handwheel for the leadscrew end by which means the carriage could be advanced more slowly and a steadier cut taken. All versions were given a T-slotted cross slide and a swivelling top slide with, on early lathes, a simple etched micrometer dial (with 80 divisions giving 0.96 thou per division) fitted to just the cross-slide feed screw - although very occasionally an original lathe is found where the owner must have pushed out the boat and ordered one for the top slide as well. Later lathes, from an indeterminate date, appear to have been fitted with both dials as standard. The slides (which were hand scraped "and fitted only by experienced slide fitters" ) carried square-thread feed screws of 12 t.p.i. with proper balanced ball handles; unfortunately the screws, instead of being fitted with replaceable nuts, ran directly in threads tapped into the castings making replacement awkward. Retained by just a single stud that passed through its pivot point, the first lathes had a top slide that was obviously inadequate and the familiar curved slot on the front, to provide an extra clamping point, must have been introduced very quickly judging by the very few examples of the first type encountered. Although precisely dating a Pre-war Myford can be difficult other pointers to early machines include a very short guard over the spindle bull gear, a lack of knurling on the tailstock handwheel and a tailstock side plate without the adjusting "gib" screws.
The gear on the end of the smaller headstock spindle simply pushed on and was connected to the spindle by a small pin passing into the face of a drive collar secured with a grub screw (in a similar fashion to that employed on the Drummond M-Type). As the lathe with the larger spindle carried a tumble-reverse mechanism the spindle-gear gear had to be a fixed distance from the tumble unit and, in effect, non-removable. To achieve this Myford (thankfully) avoided forming the gear as part of the shaft but instead made it a close fit on the (turned-down) end with a screw inserted longitudinally between gear and shaft. The changewheels (20 D.P. and 20-degree pressure angle like those on the later & Series lathes) drove down to a 5/8" diameter, 8 t.p.i. leadscrew with a square thread clasped by cast-iron nuts running in short V-edged guides fitted with adjustable gib strips.
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1938 3.5" x 23" ML.3. Another advertising picture created by art work from early and late models. Note the bolt-on headstock with front retaining nuts on top,  the lack of tumble reverse, the top slide still held by just one bolt (at the back) - and the new and improved tailstock side plate recognisable by the four screw heads.

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As a point of interest the writer has seen many examples of early Myford lathes where an owner has attempted to engage backgear by disengaging the bull wheel from the spindle; unfortunately this wrecks both gear and spindle and the correct method is to release the pulley from the spindle (look for a grub screw through either the bottom of a V-groove or through the pulley's end boss).
By far the weakest part of the lathe was the tailstock with its 8 t.p.i. square-thread spindle: the first design had no horizontal "gib-type" setting screws on the side plate though  later ones (the majority) were so equipped and allowed the plate to be accurately set whilst the two vertical clamp bolts were tightened. Unfortunately, on both types, tightening the nut or operating the lever to clamp the tailstock to the bed caused the plate to flex and the in-line setting to be lost. In fact, so poor was the original tailstock that Myford issued a sales leaflet extolling the virtues of a much-improved (and expensive) replacement. However, one good point about all Myford tailstocks, both old and new, was (and is) the locking arrangement provided for the barrel. Unlike the horrid slit in the casting, closed down by a bolt that has featured on so many other inexpensive (and occasionally expensive) machines, all Myfords have a proper split-cylinder clamp that acts directly on the barrel - and with its mounting stud screwed deep into the casting.
Two stands were produced, early and late, both of cast-iron construction. The older model was lightly built and is easily recognised by the large decorative letter M cast into each leg. The early stand was sized differently for the 3.125 and 3.5-inch lathes and could be had as a plain assembly (in 1939 £3 : 0s : 0d for ML2) or complete with either a treadle and flywheel drive or a rather clumsy countershaft that bolted to the underside of the chip tray with the drive section cantilevered backwards behind the headstock. Although the fully-motorised stand was only £5 : 13 : 6d, this represented an almost 50% increase in price over the basic unit - and more than 50% of the price of an ML2 - no wonder that today they are rarely found. Not helped by simply hanging the motor from a thin bar between the stand legs (with no tensioning arrangement) the flat-belt drive from motor to countershaft was utterly hopeless. Whilst for use today, with a  modern endless belt fitted, it is not necessary to change the headstock drive to a V-belt, the drive from the motor is definitely a candidate for change. The later stand, from 1943, was of very more substantial construction and, with its deep chip tray and three sheet steel shelves resting on cast-in plates was, in effect, a miniature version of that used on the Myford/Drummond M-Type. The long countershaft, also a smaller replica of the type used on the M-Type, was heavily constructed and pivoted from a plate bolted to the back of the headstock end leg; fitted with double-step motor and top pulleys (and in conjunction with backgear) 12 all-V-belt-drive speeds were available. Locked tight by an over-centre lever the tension of the headstock drive belt could be finely adjusted  by a left-and-right-hand threaded turnbuckle - a system still used years later on the ML10.
Unfortunately the only ML.1, ML.2, ML.3 and ML.4 parts that can be replaced by those from the later ML7 lathes are the screwcutting changewheels, the complete tumble reverse assembly and (thinned down) the backgear "Cluster" - the pair of gears carried on an eccentric shaft at the back of the headstock on the older machines, and under the spindle on the ML7. If the lathe is a late-model ML4 with a 1.125" hole through its bullwheel (the large gear carried on the spindle) this item can also be adapted, again thinned-down a little, from that used on the ML7. The changewheels ran directly on their mounting studs - the gears being joined by tiny pins (3/32" in diameter and 3/8" long) when assembled as a compound drive. Although the ML7 and Super 7 changewheels are the same D.P. as the ML1 to ML4 type, they are mounted in a much-improved way with the centre of each gear accepting a keyed bush that turns on a hardened stud. This vastly improved system is one that can easily be adapted - with a little judicious filing of the banjo slot - to work on the ML2 and ML4. If necessary the later gears can be run on the original plain studs but the additional cost of the keyed studs is so small - and the improvement in the drive so great - that this should not be considered. To use the existing changewheels on new studs requires means filing a keyway, a job made easy by buying a good quality square-section needle file just a little smaller than the size of the finished slot. As a point of interest, some changewheel brackets have been found with the faces at each side of the long slot unmachined - the uneven surface causing the gears to tilt over when their studs are tightened; the only solution is to have each side of the bracket ground or milled flat. Because the (stronger) ML7 tumble-reverse assembly is a direct replacement for the (flimsier) unit used on the ML4, there seems to be no good reason why a lathe without this facility could not re retro-fitted with it - though care would be needed in positioning the mounting stud and to marking out the indent positions for the location plunger. If you are puzzled by the cast-in fork at the back of the headstock this was used to carry an extra changewheel to provide a reversal of the leadscrew drive and so cut left-hand threads.
Most ML.1 to ML.4 lathes were supplied as standard with a 6.5" diameter faceplate, 10 changewheels (together with two mounting studs, two driving collars and a distance washer) a chuck backplate and two Morse taper centres in tool steel. Happily, large numbers of these popular machines are still in use and, whilst many are now seriously worn, some model engineers are able to produce the most amazing work on them.  Myford lathes of the early 1930s were painted black but at some point towards the middle of the decade the makers switched to what they described as a "grey/blue" finish but which, in fact, resembled a dreadful shade of "vomit green."
A wide range of useful accessories was listed for all types including a very rare "foot motor" (a self-contained, treadle-powered 56 lb flywheel and flat-belt cone-pulley assembly) for bolting under the owner's own bench, cast-iron stands that varied from the flimsy to the robust, countershafts for bench, stand and ceiling mounting, plain and swivelling vertical milling slides (though these were much lighter in construction than those for the later 7 Series lathes), travelling and fixed steadies (the latter of the slenderest proportions), machine vices, V-blocks, thread-dial indicators, a wood-turning hand rest, 4-way toolpost, saw table (very rare), plain a V drill pads for the tailstock and extra changewheels: 127 teeth for metric translation and 38, 64, 70, 75, 80, 85, 90, 95 and 100 teeth to extend the threading range. The lathe could also be adapted for light production work with the makers offering a cut-off slide and 4 and 6-hole bed and cross-slide mounted capstan heads. In addition, a number of ML2 and ML4 lathes were sold ready-converted with capstan equipment - whilst during WW2 (under pressure to make the most of all productive industry) a surprising number of other types, all branded as being variants of the ML6, were more seriously developed using different beds, headstocks and drive systems. Further details of Myford production lathes can be found here and here.
It is interesting to note that a version of the ML.4 continued in production until the early 1980s in the guise of the Perfecto in the UK and the "Advance" in Australia, though in the latter case only until (it is believed) the late 1950s. Both these latter machines sold into a niche market offering enthusiastic amateurs the chance of a new, good-capacity small lathe at a price considerable below that of the (admittedly far-superior) ML7.
Myford have no spares for the ML1 to ML4 range and, unfortunately, cannot supply any written or illustrated material about them. Instead please email for details of the interesting literature pack available from lathes.co.uk.
In order to obtain a feel for the 1930s, when Myford were manufacturing their early lathes, it is instructive to look to America where Atlas were offering the 3-inch centre height  Model 6-inch, a mass-produced machine whose neat design and comprehensive guarding may well have inspired several features used on the post-war ML7. A comparison of these models, and their drive systems, makes for interesting reading.
*Pre-WW2  the most popular English makers of small lathes for the amateur market included:  Adept, Drummond, ETA, EXE, Granville, Grayson, Ideal, Mellor, Pools, Portass, Randa, Relm, Wade-CAV, Winfield and Zyto.
Tony Griffiths

Of light construction the early stand is easily recognised by a large decorative letter M cast into each leg. The unit  could be fitted with either a treadle and flywheel drive or, as shown, with a motorised  countershaft (of clumsy design) that bolted to the underside of the chip tray with the drive section cantilevered backwards behind the headstock. Not helped by simply hanging the motor from a thin bar between the stand legs the flat-belt drive from motor to countershaft was an utterly hopeless arrangement.