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Continued:
Myford Super 7 Plus "Big Bore"
Although designed in the late 1950s, it was not until the Summer of 2001 that the last (Mk. 3) version of the Super 7 lathe was introduced. Welcomed as a long-overdue development of this classic lathe, it had a larger and stiffer spindle able to pass a 1-inch diameter bar (formerly limited to 0.75"), a M42.5 x 2 mm pitch nose and a 4 Morse taper socket. The greater convenience of the larger bore, the ability to carry a 5-inch diameter chuck and the increased mass of the headstock casting all contributed to a markedly-improved machine. Another significant and important change was made to the countershaft unit - the 2-step motor-to-countershaft belt and pulleys were changed to a Poly-V type giving much smoother running on top speed (a feature often lacking on earlier models) and extended belt life. However, on the ordinary "Big Bore" the drive from the countershaft swing-head to the spindle remained as before - a standard A-section V-belt that could be expected to give years of reliable service. To improve the feel of the cross-feed when using hand feed a needle roller thrust bearing was fitted to the cross-slide end bracket. The opportunity was also taken to improve the security and safety of the changewheel and countershaft belt guards - the inner and outer out sections were made much thicker and fitted with positive-action, 1/4-turn catches to replace the former rather weak spring-held closures that could easily be knocked open by a light blow in the right direction.
Fitted with numerous extras as standard, the top-of-the-range version was given the slightly embarrassing title of "Connoisseur". This version featured an inverter-controlled, variable-speed drive from 26 to 3000 r.p.m. , a spindle clutch, screwcutting gearbox, hardened bed, spindle indexing (by use of the backgear bullwheel), Poly-V drive to the headstock spindle and ready-mounted on the late-type industrial stand.
More photographs of the Super 7 Plus
Myford Super 7 Connoisseur
Fitted with numerous extras as standard this was the last Super 7 to be introduced. Amongst the expensive additions were an inverter-controlled, variable-speed drive from 26 to 3000 r.p.m.; crewcutting gearbox; hardened bed; spindle indexing (by use of the backgear bullwheel); Poly-V drive to the headstock spindle and the "new-type" industrial stand as used on the 254.
ML7 Tri-Leva:
Designed to fit the headstock of the ML7 (but not Super 7) the Tri-Leva was an attachment intended to perform both as a clutch and allow instant changes of spindle speed. The device was beautifully made and finished and consisted of a lower housing (bolted into place under the headstock spindle by three extended-thread headstock bolts) that acted as both a mounting shelf for the upper part of the unit and an alignment guide for the three permanently-mounted drive belts that formed the heart of the conversion. The upper part of the unit, fastened to the countershaft, held a similar belt guide and three spring-loaded rollers, each of which could be pressed down to engage its own V belt. An interconnecting mechanism released the "engaged" selector when the handle of another was depressed. The Tri-Leva was expensive, especially when equipped with the optional two-speed motor and associated switches; in 1962, for example, it would have added 35% to the £70 : 15 : 0d cost of a Standard ML7. As a result, most units appear to have been fitted on lathes bought by professionals and intended for production work. More Tri-Leva details can be found here
Myford ML7R:
Introduced at more or less the same time as the power cross feed Super 7, this is the lathe that confuses people new to the make. Although called an ML7 - and you would therefore expect it to be a development of, or directly related to, the original machine of that name - it was actually a non-power cross feed Super 7, but without a clutch and fitted with ML7 cross and top slides. It was designed to replace the ML7 and allowed a rationalisation of production around just one type of bed, headstock and tailstock. However, the lathe was not to last, and later the lathe was to be fitted with Super 7 cross and top slides and the "new" lathe renamed "Super 7 Sigma". Photographs of the ML7R here
Approximate weights with electric motor:
Standard ML7: 185 lbs. (84 kg). Long-bed ML7: 215 lbs (98 kg)
ML7R: 240 lbs (109 kg) Long-bed ML7R: 270 lbs (122 kg)
Super 7: 245 lbs. (111 kg.). Long bed Super 7: 275 lbs (125 kg)
A screwcutting gearbox adds about 15 lbs
Drive Belts - Lengths required:
Super 7 & ML7R: Headstock spindle belt A section 29.5" (use 750 mm)
Motor to countershaft M section 33.5" (use 850 mm)
ML7: Headstock spindle belt A section 23" (584 mm)
Motor to countershaft Z/M section 347/16" (875 mm)
Tri-leva: Headstock spindle (3 belts) A section 23" (584 mm)
Motor to countershaft M section 347/16" (875 mm)
(All these belts, standard and link, are kept in stock for delivery by return of post)
Myford ML10:
Now out of production in all its forms, the ML10 at 3.25" centre height and 13" (later 18") between centres was Myford's smallest modern lathe. Designed as an economical machine, especially suitable for beginners, the first one left the production line on November 14th, 1968 (though brochures had been received by dealers as early as January of the same year). With a flat-topped, V-edged bed (identical in form to that employed on the wonderful toolroom Hardinge HLV-H lathe) the ML10 was a perfectly-adequate small machine tool - though it did lack several of the refinements to be found on the company's larger lathes i.e. there was no gap in the bed, no tumble reverse, the backgear was not mounted on an eccentric but in a slotted bracket - and the headstock was clamped rather than bolted to the simple, flat-topped, box-section bed casting. It occupied 35.75" in length (an ML7 was 42") and around 22" in width (almost identical to an ML7). On pre September 1985 models the countershaft/motor-unit was a separate assembly that had to be mounted on the bench, behind the lathe, with an adjustable "over-centre" belt-tensioning device to couple them together. Later machines, from Serial No. 159991 on the 11th of September, 1985, were improved and the lathe mounted on headstock and tailstock raiser blocks with the former being extended backwards to form a mounting for the motor-countershaft unit. Thus, like the ML7 and Super 7, the lathe became a complete unit and much easier to install and transport.
With three direct-drive and three geared slower speeds the ML10, unlike most of its European and Far-eastern competitors, had a proper, robust backgear assembly (the backgear bull wheel on the spindle was identical to that used on the ML7) and, so equipped, a very powerful drive was available with the slowest speed of 25 r.p.m. enabling it to cope with large diameter jobs and screwcutting. In addition, instead of miniature (and expensive) "Gates" belts Myford chose to use reliable, full-sized, inexpensive and easily-obtained "A" section V-belts.
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:
Available in both full metric and imperial versions each had compound-slide feed screws, micrometer dials and the leadscrew to the correct specification. To convert an imperial machine to metric screwcutting required only two 21t changewheels in addition to the normal set (it was not necessary to change the leadscrew) - while to convert the rest of the lathe to a metric specification (or the other way round) needed only the substitution of the correct cross and top-slide feed screws, nuts and micrometer dials. 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 imperial 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. On imperial machines from Serial No. V144354 the diameter of the threaded side of the leadscrew was increased from 5/16" BSF to 3/8" BSF with the same increase on metric versions from V144464.
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 - the first time that Myford had ever used this marketing technique. 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:
** Ted Barrs served his engineering apprenticeship during the 1920s, completing it alongside his best pal, Bill Day, who went on to found The North London Saw Works, at Waltham Cross - a business still running today (2014).
In 1931 Ted married and, with twin daughters born in 1935, moved to Beeston in 1942 to take up employment with Myford. Like most of his generation in senior engineering positions he was a hands-on man and, when his apprentices found a job too difficult, he would go down to the shop floor and demonstrate how it should be done.
Popular with both the owners (the Moore family) and with the workforce he rose to become Works manager. However, even after he retired he would spent many hours each week at the factory in an 'advisory' capacity - he really did live and breathe Myford machine tools.
Every year his young nephew Phillip, together with his father, I would go to the Model Engineering Exhibition in London, not only to see the models on display but, just as importantly, to see Ted. One visit Phillip spent an hour on the Myford stand learning woodturning from their demonstrator, a Mr. Fred Payne; "He taught me more about the craft in an hour than I would ever have learnt at school in a year."..
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