email: tony@lathes.co.uk
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Excel Lathes & Other Machine Tools

Excel Die Milling Machine   Excel-branded BCA Mini Jig Borer

Excel-branded No. 1 Jig Borer


Used by the B. Elliott Machinery Group (Victoria, Cardiff, Progress, Invicta and others) to market lathes, specialised tool and jig millers, miniature jig-borers-cum-drillers, small jig borers, precision filing & sawing machines, tool & cutter and surface grinders & other machine tools from the 1930s until the 1960s; the Excel name indicated that the various products would be of better-than-average quality and usually directed towards a specialised segment of the market.  4.5" centre height by 12.5" between centres Model L3N, manufactured in Great Britain by an unknown company within the Elliott group. It was openly advertised as being of the "Boley & Leinen Type" and very closely followed that company's ideas for the design of a simple but very high-class bench lathe capable of the finest quality work. Although not a machine intended for amateur use numbers of the lathe were pressed into service by clockmakers and model engineers and was, at one time, surprisingly common on the second-hand market, a situation that probably indicated the government taking quantities of them during and possibly after World War 2. The writer was lucky enough to have several examples pass though his hands during the 1970s and can personally vouch for their longevity and high quality. However, Elliott were not the only company in the field for, at the same time (during WW2 when  supplies from the Swiss Company Schaublin and, of course, German machines by G.Boley, Leinen, Lorch  and Wolf Jahn were not available) precision bench lathes were also being manufactured by, amongst others: BensonBWC, Cromwell, CVA, Holbrook and Woodhouse and Mitchell (though only one example of the latter has so far been found) .
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3/8-inch long, the bed and its mounting feet were cast as one with stiffening ribs adding to the rigidity of what was already a very heavy casting. The bed ways consisted of a front V and a rear flat, both ground finished and carrying, as standard, just a hand T-rest that was supplied with both wide and narrows rests; available as an option (at what would have been considerable cost), was a very well constructed compound slide. This unit, with its all-ground finish on both working and cosmetic parts, was normally supplied with screw-feed on both cross and top slide but examples have been found of the L3N with all-lever feed slides and both a lever cross slide with a screw top slide - and a screw cross slide with a lever top. It is not known if the much greater variety of slides produced for the Leinen and Boley & Leinen versions were available for the Excel but the fact that components were  interchangeable between the makes would have helped the more impecunious enthusiast who could have looked to the second-hand market for parts. The standard toolpost was the usual triangular clamp but, as a rather thoughtful touch, fitted with a rotating strip that prevented the end of the levelling screw from marking the top slide surface. An American-style toolholder was also available but, instead of being fitted with a separate dished "wooble" washer (that allowed the curved "tool support" to rock the tool point up and down), formed the dish direct into the metal of the top slide.
Bed fittings were secured by long bolts though-bolts terminating in large hand-nuts with rather uncomfortable-to-grip flat wings; however, if the lathe fell down on this small but easily corrected point, the 2-inch diameter compound slide-rest micrometer dials made up for it: of the zeroing type, and with especially clear engraving and easy-to-grip knurled edge rings, they were exactly the same as those used on Leinen and Boley & Leinen lathes of the late 1930s and, it must be said, a complete departure from earlier tiny units (first used during the 1800s) with their distinctive "narrow twin-ring" knurled grips. As a further refinement the longitudinal fit of the dials on their feed screws (and hence any backlash), could be precisely adjusted by the manipulation of two miniature C rings. Both feeds screws were 10-t.p.i. and made from nickel-chrome steel, ran though adjustable phosphor-bronze nuts and were completely enclosed beneath the slides and so protected from swarf and dirt. The long-travel top slide top slide could be swivelled 45
° each side of zero and carried a single triangular toolpost supported by a spring and with a knurled levelling screw.
Continued below:

Excel lathe Model L3N 4" x 12.5"

Continued:
Carefully designed and beautifully constructed, the headstock casting was secured by a quick-action eccentric clamp that engaged with a T slot that ran the length of the bed whilst the hardened, ground and lapped 63/64"-bore spindle ran in what were described as: "
special hard bronze cylindrical adjustable bearings with hardened and polished journals Ring Oil lubricated." Although of parallel bore each bearing had a tapered outside and, when drawn into its tapered socket by screwed rings, was closed down slightly on the spindle. The makers claimed that, before final assembly, each spindle and its bearings were subjected to: "careful testing after running for long periods at 2500 rpm".
If it ever proved necessary to re-adjust the bearings the merest trace of drag was introduced into the assembly and then, after a run for 30 minutes at top speed, a check made to ensure that, though they may have become "warm", they did not get "hot".
In order that pull from the belt would not interfere with the smooth running of the spindle, the 3-step flat-belt "cone" pulley (with diameters of 2.75", 3.75" and 4.75") was supported in its own ball journal bearings with the drive transmitted (to the spindle) by a keyway. End thrust was absorbed by ball thrust race, adjustable by a pin spanner, whilst the outer flange of the largest diameter pulley had hole to accept a locking pin than ran through a boss on the front face of the headstock. The spindle nose was threaded to mount chucks and faceplates and bored to accept a standard spring collet; each machine was provided with draw bar and a single collet carrying a No. 2 Morse taper centre - there being no provision to fit an ordinary centre in the spindle itself. In order to protect the spindle thread from swarf, dirt and damage from mishandling of the cutting tool when close to the spindle nose and with collets in use, a knurled screw-on "guard nut" was thoughtfully provided.
Continued below:

The beautifully constructed compound slide rest

Continued:
Although various countershafts were offered, including bench and ceiling types, the lathe could also be had on a neat underdrive stand (of which, unfortunately no picture survives) almost certainly very similar to that offered for the Boley & Leinen equivalent. When mounted in this way a different headstock casting was used with a hinged top cover and both its front and back faces spaced out to accommodate the drive belt. Although spindle speeds were advertised as running from 200 to 2000 rpm the actual range would, of course, have very much depended upon the type of drive system chosen by the customer and the motor rpm..   
Unaccountably, apart from the window in the casting to show the division scale, the tailstock differed from the traditional pattern fitted to this type of precision lathe. Instead of the spindle's full length passing through the casting, and emerging from both ends (to give maximum possible support no matter in what position), on the Excel a conventional centre-lathe design was used with reduced support as the spindle was extended. The No. 2 Morse taper centre was self-ejecting and the barrel, locked by a proper compression clamp, had a just-adequate 2-inches of travel.
It is not know precisely what accessories were available for the Excel but the Leinen and Boley & Leinen versions were offered with a comprehensive range including bed-mounted capstan units for production work; chase screwcutting equipment; conventional screwcutting using changewheel together with power feed to the top slide; steadies; various kinds of toolpost; a number of different tailstocks and micrometer stops, etc.
The Excel L3N had a gross weight of approximately 200 lbs and required a bench space of 401/3" x 24"..

Above and below: headstock assembly showing the main casting, spindle, pulley and bearings

Catchplate and standard collet

For comparison - the Boley No. 3 & No. 4 (90 & 120 mm centre heights)

An Excel with an "American" toolpost. Note the height-adjustment wedge (normally sitting on a separate "Wobble washer") bearing directly against a hollow formed in the top surface of the slide.

Excel specialised tool and jig millers, Excel small jig borers,

Tailstock cut-out to expose the ruler graduations on the barrel

Excel tailstock with, to the rear of the barrel clamp, a recess and dipper rod for the purpose of holding and applying (poisonous) white lead to the lathe centres.

The hardened, ground and lapped 63/64"-bore spindle ran in what were described as: "special hard bronze cylindrical adjustable bearings with hardened and polished journals Ring Oil lubricated." Although of parallel bore each bearing had a tapered outside and, when drawn into its tapered socket by screwed rings, was closed down slightly on the spindle. The makers claimed that, before final assembly, each spindle and its bearings were subjected to: "careful testing after running for long periods at 2500 rpm".

A well-used Excel but the quality and clarity of the large micrometer dial is evident

Excel Die Milling Machine   Excel-branded BCA Mini Jig Borer

Excel-branded No. 1 Jig Borer

Excel Lathes & Other Machine Tools
email: tony@lathes.co.uk
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