Harrison were established in 1898, initially as textile machinery manufactures - yet it was only two years later that they produced their first lathe. Harrison machine tools have always had an excellent reputation for robust, but user-friendly design, the employment of good-quality materials and have long been popular both in Great Britain and abroad. Many thousands have been supplied to UK schools and colleges as well as every variety of industrial location - and considerable numbers exported worldwide, especially to the USA and Canada. In addition to lathes a limited number of milling machines were offered and today they offer various CNC models and a range of modern, conventional lathes, the M Series, fitted with variable-speed drive as the V350, V390, V460 and V550. All these types, together with the smaller, older versions, are in great demand, especially the latter type for use by model engineers, home-shop machinists and in smaller professional machine shops. The notes below concern the pre M-Series machines, mainly variants of the original L.5 Model. A partial list of Serial Numbers can be found here.Harrison L.5, L.5A, 11-inch, 140 and L.6
One of the problems in identifying specific models of Harrison lathe made during the period 1938 to 1965 is the lack of a nameplate; some lathes, especially the later 11-inch, 140, 155, 165, 190, 13-inch and 15-inch types, did have them, but by no means all. Even the sales brochures and price lists are of little help for many lack model-type designations and simply refer to machines as "9-inch swing", "11-inch Swing" and "13-inch swing", etc. Sometimes the letter L appeared before the centre height - as in the very early L2 and later L.13 - but not always, and occasionally price lists used the L prefix, but again, not in a consistent way. The only sure way to discover what you have is to measure the centre height and then carefully compare the machine with the pictures available in this section of the Archive.
Very old Harrison lathes are rare, with hardly any pre-1935 though to exist. At the cheaper end of the used market the most common model is the geared-head, clutch-equipped 9-inch (229 mm) swing L.5 - though the almost-identical looking 11-inch (279 mm) swing L.5A is a far better bet - and often hardly any more expensive. The L.5, with its all-geared headstock, was introduced in the early 1940s as a development of an earlier series and was the company's smallest true industrial lathe. Priced at around £180 - compared to £560 for the largest 16-inch - it ran, with only minor mechanical modifications and specification changes, until the mid 1960s when the smaller models in the range were joined by distinctly-different but short-lived 10-Inch and 12-Inch lathes. Then, from around 1968, a very much more modern-looking Mk. 3 L.6 and 13-inch and 15-inch models were introduced - the latter types also badged with their metric-equivalent numbers as the Models 155, 165 and 195. These lathes were, in effect, early versions of the M Series with similar aprons, screwcutting gearboxe and other smaller parts. However, even by the early 1970s - and despite new models and the introduction of the quite different M300 - some of the older machines were still in the catalogues.
Harrison's range included, from the late 1930s until the early 1970s, the following:
9-inch/11-inch flat-belt drive L2
9-Inch model L.5 centre height 4.5" (9" swing - see the article below and here)
11-Inch model L.5A centre height 5.5" (11" swing - see the article below and here)
140 (140 mm swing) a late model 11-inch with a modified headstock
10-Inch (and a 12-inch version both very rare mid to late 1960s models)
11-Inch (mid 1960s and also found badged as the "Clearing" in the USA and Canada)
12-Inch/13-inch L.6 in Mk. 1, Mk. 2 and Mk. 3 versions (badged variously as 10", 12" and 13" models for home and export markets)
Models 155 and 165
13-Inch (early L13 home-market)
13-inch late Model
15-Inch late model
Harrison Graduate Wood Lathe
Harrison Jubilee Wood Lathe
Harrison "Union" Light-pattern wood and metal lathes
AA-10 VS a re-badged Colchester Chipmaster for the export market.
500S capstan version of the late-model, 5-inch centre height, variable-speed drive Boxford VSL; probably for export only.
The various machines are easily confused and, because the two smallest, the L.5 and L.5A, used the same bed casting can look, at a glance, identical. The writer has been to dealers where, with several Harrisons on offer, the tailstocks from lathes of different centre height had been accidentally (or maliciously) swapped over - so take care.
A complete data pack is available for these lathes
More on the Early L.5 More on the Late L.5 Summary of L.5 Year Features
In the years leading up to World War two, and the production of what was to become the well-known L.5 lathe, the Harrison range consisted of: the Model J.L.1 5-inch "Jubilee" woodworking: the Model L.1.A "Union" light-pattern plain-turning lathe - this being made with a permanent gap bed and in centre heights of 3.5, 5 and 6 inches and driven by treadle, countershaft or directly from a motor held inside the headstock-end leg: also available were a pair of similar but better-specified models, the "Union" 3.5-inch L.1.A.S. and 5-inch L.2.A.S. with backgear and screwcutting - and again with a choice of drive systems to suit the purchaser's circumstances: more industrial and heavier in appearance was the "Improved" L.2-6, available as a either a 4.5-inch or 5.5-inch model and with either flat-belt drive or a geared headstock - this was the lathe that would, during the war, become the basis of the L.5 range and develop into the most popular and widely-sold of the company's models; the largest machine to be offered was the L.21 "Toolroom" equipped with a screwcutting gearbox and sold with flat belt drive as the L.21 or, in geared-headstock form, as the L.21.A.
The L.5, the subject of this article, has a deceptive appearance for, although its weight and bulk were nearly as great as a Colchester student (and it was a very strong machine) its centre height was only 4.5" (114 mm); the L.5A had its capacity increased to 5.5 inches (but was otherwise largely unchanged) whilst the "11-inch" and "140" models were late production variants with a specification that had been steadily improved to help cope with heavier work and higher speeds. Both standard and long-bed versions of all models were made, offering either 24" or 40" (508/1016 mm) between centres.
The L.5 was never given "Mark" numbers to distinguish the numerous minor changes made to it over the years; however, a summary of these differences, and an approximate guide to the year of their appearance is:
Flat-belt & Geared Head Drive: late 1930s to about 1946 with a light bed foot under the headstock and a spoked handwheel on the carriage traverse. This was not an L.5 but its immediate forebear the previously-mentioned L2-6.
Mk. 1 Geared Headstock - late 1930s (as the "Improved" L.2-6) and developed until around 1945: 3/4" bore spindle running in plain bearings; a lift-off headstock cover with the letters "A" and "B" cast into the front face; micrometer markings engraved into the flat rims of the cross and top slide handwheels; cast-iron plinth under the headstock and a simple leg under the tailstock end of the bed (although some full cabinet stands in cast iron were also manufactured); flat-sided, triangular form, cast-aluminium bolt-on changewheel cover; a clutch operated by a bed-length horizontal bar and the power feeds engaged by a lever with a bronze trigger.
Mk. 2 - 1946 to 1949: full-length cabinet stand fabricated from heavy-gauge sheet steel; roller-bearing headstock with a smaller, bolt-on top cover with a raised rib around its lower front edge and a small spindle-speed plate in the centre; conventional zeroing micrometer dials; large bolt-on changewheel and belt cover cast in one piece with two curved faces to the front; short clutch operating lever pivoting on just the headstock.
Mk. 3 - 1950 to 1956: headstock spindle with the option of either 0.75" or 1.25" clearance through the bore (the latter very rare indeed) and the headstock cover without the "A" and "B" letters but with a larger spindle-speed chart often protected by a transparent plastic plate; large cast-aluminium combined changewheel and belt-guard with hinge-open gear cover; tailstock barrel clamp positioned vertically at the rear rather than horizontally over the top of the smoothed-off casting; exposed spring and bronze thumb catch removed from the apron-mounted power-feed engagement lever and its material changed to a metal rod; leadscrew reverse control knob changed from solid steel with a knurled edge to plastic with seven finger grips; 3-speed feeds and screwcutting gearbox with downward-pointing cast-iron lever changed to an enclosed type with an upwards-pointing rod lever; Harrison nameplate attached to a headstock-mounted plate as well as appearing on the bed - and sometimes the stand as well.
Mk. 4 - 1957 to 1966: cross-feed and carriage traverse handwheels with 3 spokes and internal finger grips; large speed-change lever on front face of headstock fitted with safety catch requiring the lever to be pulled out before it could be moved sideways. Although the L.5 continued to be advertised during the early 1960s the 5.5-inch centre height L.5A was already in production by 1958.
Originally fitted with a removable gap piece as standard by the 1950s, as straight-bed hydraulic-copying lathes were introduced, the gap on the ordinary lathe became an extra-cost option. The gap made a substantial difference to the capacity of the lathe, for, even on the 4.5" centre-height model, it allowed work up to 4.25" (114 mm) thick and 17" (432 mm) in diameter to be turned - and up to 18.75" (476 mm) on the 11-inch swing L.5A. The beds of early lathes were not hardened and, even through this process was offered as an extra, it is rare to find one so specified. Later models, from an indeterminate date some time in the mid 1950s had hardened beds as standard. Very occasionally an example of the L.5, from the mid 1940s onwards is found mounted on a full-length cast-iron cabinet stand - as are (surprisingly) very limited numbers of later models. However, no mention is made of this stand - nor are any pictures evident - in any of the many catalogues seen by the writer. Although early lathes are generally found supported at the headstock end on a cast-iron plinth with a simple leg at the tailstock end, by far the most common Harrison stand is one fabricated from heavy-section steel plate with a locking storage cupboard and deep chip tray.
The headstock of the L.5 was always fitted from the start of production with a combined clutch and brake unit, a fact that makes amateur operation by a single-phase motor very much easier. Unfortunately, although a reliable unit, the clutch on all models is prone to rattle, a situation nearly always exacerbated by the use of a single-phase motor or a phase converter. The first L.5 models of the 1940s had a headstock spindle running in plain bronze bearings but all later versions, from the late 1940s, were fitted with pre-loaded, opposed Timken taper roller bearings at the front of the headstock spindle and a single-row ball bearing at the rear; the main double gear that slid along the spindle was cut from a single forging and slid on six (later seven) splines - the complete assembly being dynamically balanced. On early machines the headstock gears were in cast iron but on later models, from an unspecified date, an improved specification was introduced with all the gears hobbed from the solid, shaved, induction hardened and honed to produce the correct tooth form. The first lathes had a spindle nose with a 1.5-inch, 6 t.p.i. thread and a bore of just 0.75" but in the early 1950s the option was offered (at extra cost) of a 2.25-inch x 6 t.p.i. nose with a must more useful 1.25" bore. When the increased centre height L.5A was introduced its spindle (with a slightly larger 1.375" (35 mm) hole was also offered on the smaller machine - though this is rarely found.
Offered first on the export market, the L.5A was, at first, just an L.5 with an increased centre height so that it could be sold, in American parlance, as an "11-inch" machine. Besides the two sizes of spindle thread/bore, one very belated extra (later to become standard) was the option of the much safer and more rigid American L00 (L-zero-zero) nose. The L.5.A eventually became the "140" and was fitted with a distinctive "square-front" headstock - and had the large-bore spindle and L00 nose fitting as standard.
On all models 8 spindle speeds were normally available (16 on lathes with 2-speed motors) with the range most commonly found on second-hand L.5/L.5A/140 machines being 31 to 720 r.p.m. However, various other options were available over the years including:
21 to 480 rpm - 1000 rpm 3-phase motor with an input speed to the headstock of 500 r.p.m. - common on early machines and also used on later ones in conjunction with a low-power motor for safety in training establishments
31 to 720 rpm - 1.5 hp 1500 rpm motor
42 to 960 rpm - 2 hp 1500 rpm motor
62 to 1440 rpm - alternative range with the 2 hp 1500 rpm motor
31 to 1400 rpm - 16 speeds: two-speed 1.5/3 hp 1500/3000 rpm motor
62 to 1400 rpm - 16 speeds: alternative range with two-speed 1.5/3 hp 1500/3000 rpm motor
22 to 500 rpm - 1 hp motor
34 to 750 rpm - 1.5 hp motor
45 to 1000 rpm - 16 speeds: 2-speed 1.5/3 hp 1500/3000 rpm motor
34 to 1500 rpm - 16 speeds: alternative range with 2-speed 1.5/3 hp 1.5/3 hp 1500/3000 rpm motor
A few lathes were also made with a special "high-speed" headstock that gave 45 to 2000 rpm from a 2-speed motor. The clutch on higher-speed model (and the 140) was supported on two ball races - instead of the single roller bearing employed on the single-speed motor versions. However, there appears to have been no difference in either the size or quality of the headstock gears and only one bush, on the layshaft, was shown in the Parts List as being different. There appears to be no reason, therefore, why the top speed of the slower models cannot be safely increased to around 1500 rpm to make them very much more useful (see below).
Screw-thread Spindle fittings L.5, L.5A
The small-bore spindle was threaded 1.5" x 6 t.p.i and the large bore spindle 2.25" x 6 t.p.i. The option of a screwed spindle nose was withdrawn on the 31st. of December, 1959.
Selecting Spindle Speeds
Because the control levers were "interlocked", to prevent the engagement of two gears at once (and work in a rather unusual way), it is not always clear to a beginner how the spindle speed should be changed; here is the method of operation:
each of the two selector on top of the headstock can be placed in one of three positions
to select a new speed, either of the two levers must first be placed in its central, or "neutral", position
the other lever can then be turned to either its full-left, or full-right position
by juggling these positions (one lever in neutral, one engaged) new speeds are selected.
However, don't expect the speed-indicator diagram to help you determine which setting you have selected - it's a masterpiece of convoluted lines and what appear to be randomly placed numbers and certainly not something that can be taken in at a glance. Before either selector lever can be moved it is often necessary, as on any gearbox with straight-cut teeth, to ease the spindle round a little to permit the gears to engage. A third, much larger lever, pointing upwards and located on the headstock front cover was used to select the high and low-speed ranges. On early models this lever had no protection against accidental movement but later a spring-loaded safety lock was incorporated that meant the lever had to be pulled out before its position could be altered.
Harrison headstocks are not noted for quiet running - although some machines do seem better in this respect than others - and is usually blamed on a combination of "ringing" from the hardened headstock gears and clatter from the steel changewheels. Providing there are no deep rumblings, or obvious vibrations, noise from the headstock has to be considered as just an annoying inconvenience. A story that emerged from the works during WW2 (and almost certainly not apocryphal) was that Russian inspectors, fearful of sending back machines to the Stalinist dictatorship that were in any way imperfect, complained that a batch of lathes was far too noisy. An apprentice was found and the machines demonstrated to him by a foreman. He was told him that one solution was to fill the headstocks a mixture of oil and a little light lapping paste and run them until they quietened down. The units could then stripped, thoroughly cleaned and new bearings fitted. However, as non of the works staff dared do this he, as an apprentice, was certainly not to try it - whereupon the foreman handed over a large can of lapping compound together with several tins of oil - and departed.
None of the speed-change levers on the headstock should be moved until the spindle has completely stopped. The original high/low spindle-speed selector on the front face of the headstock could be moved freely from position to position and so had no protection against being accidentally moved when the machine was running. On Mk. 4 models, from approximately 1959, the option was offered of a spring-loaded safety "guard" that required the handle to be pulled outwards before it could be moved; this fitting was eventually provided as standard.