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Continued: 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
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