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Continued:
ML10 Headstock:
On early and late machines the headstock was different. The first model, with six speeds and a maximum of around 840 rpm, had a hardened spindle that ran directly in split bearings formed as part of the headstock casting. This combination of hardened steel running in cast iron (partially self-lubricating due to the free graphite found in the latter) is excellent from the wear point of view - and I have yet to find any ML10 with the headstock bearings in poor condition. You may be quite confident that this design principle is correct - tens of thousands of American South Bend (and other makes) have been constructed in this way - and are still going strong. The bearings on the ML10 were split on one side only and provided with a clamping screw; the space between each split was filled with a thick shim to provide a firm surface onto which the top cap could be pulled down. If the headstock bearings appear to be in correct adjustment it is important not to fiddle with them; simply ensure that they receive regular lubrication - and under no circumstances remove the shims. It is possible to vary the speed range of an ML10 by changing the size of the electric-motor pulley, but do bear in mind that the maximum recommended speed of a plain-bearing ML10 is 1280 rpm. Later machines, produced from January 18th, 1978, (from machine V137261) were fitted with grease-lubricated roller-bearing headstocks that, although provided by the factory with the same speed range as the earlier machine, can easily and safely be adapted by their owners to run as fast as the later "Speed 10" version (see below for details).
ML10 Changewheels, Screwcutting and Metric Conversions:
Originally supplied in both full metric and imperial versions the latter is by far the most commonly available second-hand. To convert an imperial machine to metric screwcutting required only two 21t changewheels in addition to the normal set - while to convert the rest of the lathe to a metric specification needed only the substitution of the inch-calibrated cross and top-slide feed screws, nuts and micrometer dials with their metric equivalents. The lack of a tumble reverse meant that a reversing stud (mounted behind the spindle in a slotted bracket) was necessary to cut left-hand threads; the changewheels and their mounting studs, fastened to a simple, single-slot banjo, were identical to those on the ML7. The leadscrew pitch was the same as the 7 Series lathes (eight threads per inch) and was available fitted with an optional and very useful dog-clutch that allowed the leadscrew drive to be instantly engaged and disengaged.
ML10 Compound Slide, Apron and Saddle Assembly:
Although the cross slide was a little smaller than that on an ML7, the micrometer dial, hand-wheel and standard toolpost were identical. The cross-slide T-slots were spaced the same distance apart (which allowed a standard ML7/Super 7 vertical milling slides to be used) but the 4-way toolpost and rear toolpost were unique to the machine. The top slide fitting resembled that on the Super 7 with an inverted cone used to take the thrust from two opposing push bars that caused it to lock down onto the cross slide.
Geared directly to the leadscrew, the carriage handwheel and incorporated a thread-dial indicator; however, because the direct gearing caused the saddle travel to be rather "high-geared" (i.e. you turned the handle a little, and the saddle moved a lot) the leadscrew was provided, as standard, with an un-graduated handle at its right hand end. Used with the clasp nuts engaged, the leadscrew able to provide a much smoother and steadier saddle movement. From machine number V167714M, on the 27th of March 1993, the previously optional-extra 'long cross slide' was fitted as standard.
Speed 10:
On the 4th of May 1979 a modified "two-speed" countershaft unit was introduced that carried an eccentrically-mounted top shaft with a double-step V-belt pulley drive from the motor; this arrangement doubled the number of speeds to twelve (of which ten were officially sanctioned as safe to use) with a range from 48 to 2000 r.p.m. This new model, the "Speed 10", was identified by the prefix "VS" and the first down the production line carried the Serial Number VS143202M. Just one month later, on the 6th of June, the first Long-bed Speed 10 was manufactured (numbered VSL144264); with its 18-inch capacity between centres this model was introduced in an attempt to bridge the gap between the ML7 and ML10.
A useful little machine, the ML10 was perfectly capable of tacking most jobs that the model or development engineer would wish to attempt, the only drawbacks being the simplicity of its construction - and basic controls. A friend, who is a full-time experimental and development engineer, bought a plain-bearing example n his impecunious days and held on to it for twenty-two years, finding it indispensable for all his small turning. With a 3-inch precision chuck mounted he often ran it (for short periods only) up to 40000 r.p.m. without any harmful effects, though he had fitted drip-feed oilers to the bearings and ran them with a high per-minute drip rate. The last incarnation of the ML10/Speed 10 was the "Diamond 10", introduced on November 27th, 1993 and only sold directly from the factory. A comparatively rare machine on the used market, the ML10 sold in fewer numbers than the larger models - although, to be fair, the latter did have a twenty-two year start.
Like other Myfords the ML10 was cloned - one version (illustrated below) being sold in the UK by the long-established importer of far Eastern machine tools, Warco.
Used Myford lathes of all types can often be found for sale on this page:
Copyright: Tony Griffiths
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