Just occasionally, instead of the more common ML2, ML4 and M-Types that emerge from under piles of rubbish at the backs of garages, there appears one of these rather unusual and heavily-built 4-inch Myford lathes.  It is thought that around five-hundred examples of the type were produced during just one year of production, 1942, with the rare advertising literature showing that Jones and Shipman, the Leicester-based grinding machine company, had a hand in either the design, production, or marketing - and may well have supplied the castings. The 4-inch was made in late and early versions with the former - an extremely rare find - also being constructed (though with a modified form of bed) as a dedicated capstan lathe. The bed of the earliest model was rather lighter than the later and had a form that might be described as "semi-cantilever" with an enormously long foot under the headstock end (with single holding-down bolts at front and rear) and a graceful upward sweep to a perfunctory support under the tailstock end. There were several other minor differences as well: the cross-feed screw ran directly in the metal of the saddle (later machines had replaceable nuts); the tailstock used a different casting, the changewheel guard was in aluminium not cast iron and the tailstock-end bearing for the leadscrew was part of the bed casting instead of being bolted on.
The lathe was advertised by the makers as the 4" -precision and was eventually made available in a Series denoted by the letter MF; the range consisted of:
MF-18.B  4" x 18" for bench mounting lathe only
MF-24.B  4" x 24" for bench mounting
MF-24.S  4" x 24" with pressed-steel stand
MF-24.M  4" x 24" with self-contained, motorised pressed-steel stand less motor and switching gear
MF-30.S  4" x 30" with pressed-steel stand
MF-30.M  4" x 30" with self-contained, motorised pressed-steel stand less motor and switching gear
MF-36.B  4" x 36" for bench mounting
MF-36.S  4" x 36" with pressed-steel stand
MF-36.M  4" x 36" with self-contained, motorised pressed-steel stand less motor and switching gear
Although the above numbers were the official listing, lathes are often found with  "MF32" and "MF74" cast into the backgear guard or stamped into either the saddle or cross slide. The "MF32" can, generally, be distinguished from the later "MF74" by its over-complex, lever-operated backgear engagement. Whilst examples of the 24" model are relatively common, the 30-inch and 36-inch must be very rare for only one of the latter has come to light in recent years together with a single example of an 18-inch early model.
Word from older Myford employees had it that the headstock of the MF32 was fitted with  "pusher screws" alongside both front and rear  front clamping bolts to help with alignment - but this feature has been noticed as absent from some MF32s yet present on some MF74s; one can only deduce that the fitting must have been included only where an alignment problem occurred, or as a post-production modification to help restore accuracy.
The 11-inch capacity gap bed was of very much heavier construction than that used on the contemporary ML2 and ML4 models; it was of deep section compared to its width and supported on robust feet, the headstock end being clamped down with four bolts.
Although the 5/8" bore, ground-finish carbon-steel headstock spindle carried a No. 2 Morse taper nose and was considerably stronger than that used on the ML2 and ML4, it still ran in simple, split, bronze bearings. The spindle nose was threaded 1.125" x 12 t.p.i. - identical to the ML7 and Super 7 - but with the "register" behind the thread set at the thread diameter. The backgear was unlike that of any Myford before (or since) being of conventional design, located at the back of the headstock with the spindle gears spaced at each end of the drive pulley; its engagement was controlled, on the MF32, by an over-elaborate, lever-operated mechanism that caused the shaft to slide in and out of engagement. On the MF74 the lever arrangement was omitted and a simple knob fastened to the end of the backgear shaft so that the operator could slide it to and fro as required.. The spindle bull wheel was guarded by a neat cast-iron cover that hinged open to allow access to the gear-pulley coupling pin - the latter being spring loaded and with an easy-to-grip knurled edge. To ensure a positive location a stiff wire cross piece was arranged to drop into a slot cut in the face of the gear.
The spindle carried either a 4-step V pulley - which seems to have been the standard offering - or a 3-step flat belt when the lathe was to be connected to an existing overhead line-shaft drive. Speeds with the V belt drive ranged from 27 through 45, 68, 109, 165, 268, 420 to 650 rpm. The V-belt drive countershaft and its motor platform were of several types: one, a remote version, fastened to the bench behind the headstock (very like that offered for the ML2/4 with a swing-head but of heavier construction); another bolted to the back of the bed with an over-centre lever for tension whilst the third version (but only encountered on two machines) used a heavy casting mounted on the back of the bed in such a way that it could be adjusted vertically. Its upper section, carrying the pulleys, was arranged to pivot under the control of a screw-adjusted rod that passed through the bed from front to back with the screw-adjustment handwheel, on the front face of the bed, adapted from standard tailstock components. Drive from motor-to-countershaft was either by either single or double V belts. A wire mesh guard, of a design not unlike that also fitted to the Myford/Drummond "M-Type", was fitted over the motor-to-countershaft belt.
Tumble reverse was standard with the changewheels carried on a twin-arm banjo very similar to that employed four years later on the ML7, but with a larger-diameter mounting boss. The gears were identical in pitch and bore to those on the ML2, ML4 and Series 7 machines; a set of 12 was standard and comprised: 2 x 20t, 25t, 30t, 35t, 40t, 45t, 50t, 55t, 60t, 65t and 95t. The gears were guarded by a swing-open cast-iron cover - that, unfortunately, lacked any form of retaining catch.
The 3/4" diameter leadscrew was threaded 8 turns to the inch and could, very strangely for a lathe of this type, be specified (at extra cost) with an improved pitch accuracy of 0.0005" in 1", 0008" in 3" and 0.0015" in 12". The leadscrew was clamped by two bronze clasp nuts held in a double-walled apron that was fitted, unlike the ML2 and ML4, with a proper geared-down hand drive onto the carriage-drive rack. A rather large and distinctive dial-thread indicator was fitted as standard  held conveniently in place by a rather well-finished knurled handwheel.
The cross slide was made in three different lengths - short, very short and (seen only on late machines) very much longer at 11 inches. Whilst the two shorter slides had a very limited travel (a situation not assisted by the end bracket being a simple plate flush with the end of the casting), the longest had the benefit a proper "stand-off" bracket that allowed the outer end of the casting to override the front face of the saddle to give a movement long enough to allow the satisfactory use of a vertical milling slide. All slides were unusual in having, like all larger Emco lathes from the 1950s onwards, two T-slots  that ran from front to rear rather than in line with the bed as on all other models of Myford. The top slide could be set to swivel 45 degrees either side of central but, as an option (or in addition to it), a robust all-steel 4-way toolpost was offered to assist with heavier types of production work. Some models has degree marking rolled into the front face of the top-slide casting whilst others were fitted with an engraved, riveted-on plate. One improvement fitted to later examples was a replaceable cross-slide feed-screw nut, similar to that on the 7s Series but in this case larger and in bronze; this was the first use of such a component on any model of Myford. The compound slide feed screws on early machines were square-section 10 t.p.i. (later ones 12 t.p.i.) and had neat, zeroing, knurled-edge micrometer dials - the latter feature not appearing again on a Myford until the Super 7 of 1953.
The set-over No. 2 Morse taper tailstock - with a 3.75" of barrel travel - was not unlike that fitted to the later ML7s - with the exception of the very much larger thrust arrangement and a correspondingly bigger and hence easier-to-use handwheel.
Two stands were available; a heavy unit in cast iron (including the chip tray) and a much lighter sheet-steel version - an example of which is illustrated below and shown in the list of machines types at the top of the page. Because the 4-inch Precision is a relatively rare lathe, and very-heavily built, this is one early Myford that is well-worth the expense of rebuilding and subsequent cherishing.
Copyright: Tony Griffiths