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E-MAIL Tony@lathes.co.uk Home Machine Tool Archive Machine Tools For Sale & Wanted Machine Tool Manuals Machine Tool Catalogues
Boxford 4.5" Precision Plain-turning Lathe Boxford Home Page Boxford Models A, B, C, AUD, BUD & CUD Factory Dispatch Line Model T Training Lathes Boxford VSL & 500 Vari-speed Boxford Accessories Miniature Precision Boxfords Larger Precision Boxford Serial Numbers Model CSB AUD Photo Essay South Bend Copies A detailed Manual & Parts List is available for all Boxford lathes together with changewheels and other spares. For more details of the lathe that Boxford copied, the 9-inch South Bend, click here For details of other South Bend Clones click here
Intended to compete with what was described coyly by the makers, Denfords Engineering, as continental manufacturers - in other words Schaublin, Mikron, G.Boley and Leinen - the Boxford 41/2" Precision Plain Lathe resembled, in its general style, the Company's ordinary screwcutting types. However, it was, in every detail (save for a few minor tailstock components) entirely different - and in no way a development of the two miniature precision lathes made by the company in the 1940s. Carried on a stand that resembled early Schaublin practice - two cast-iron legs of rectangular form being joined by a cast-iron chip tray - the 36-inch long bed had V and flat ways of a pattern unique to the model. The stand was enclosed by steel plates to form, on the left, a compartment for the electric motor and (expensive) Allspeeds "Kop" swash-plate variable-speed drive unit and, on the right, a collet rack and tool and accessory storage. The headstock held a 1.125" bore spindle (to clear 1-inch diameter bar stock) running in precision taper roller bearings (2" diameter at the front and 17/8" at the rear). In order to mount chucks and faceplates - as well as a large draw-in, collet-holding adaptor - the 2-inch diameter spindle nose was threaded 7 t.p.i. In conjunction with the variator and a 3-step headstock pulley, a 3/4-h.p. 2800 r.p.m. motor gave speeds from 220 to 2000 r.p.m. Drive from motor to variator was by Brammer (link) belting (adjusted by adding or removing sections) with the final drive by flat belt. The makers took great care to ensure that the latter ran as efficiently and as slip free as possible by passing it over two adjustable jockey pulleys, the positioning of which not only added tension but also created extra wrap-around on both drive and driven pulleys. If only more makers could have engineered such a system into their similar models. The compound slide rest was available in two forms: a standard unit and another (at extra cost) able to mount Fiducial indicators and slip gauges - a Fiducial indicator has two fine lines, set opposite one another and arranged so that, when brought level, a datum position is determined with great precision. Top slides with both one and two T-slots were shown in the catalogue, though if one superseded the other is not known. Both cross and top slides had 5 inches of travel, the latter being able to swivel through 360° - with the graduations on its base marked to 180°. Feed screws were rolled with an Acme-form 10 t.p.i. thread and fitted with ball end-thrust bearings to improve sensitivity and feel. Of decent size, the micrometer dials were engraved with 100 divisions, each representing 0.001". Enclosed under the casting, the cross feed screw needed no further protection but that on the "open-way" top slide was covered by a snug-fitting cover made from spring steel. Like the base of the headstock, that on the (ordinary-looking) tailstock was hand scraped to the bed for a perfect fit. With 3 inches of travel and a No. 2 Morse taper, one might have imagined that, on this lathe, the spindle would have been fitted with a micrometer dial as standard. Indeed, on later models this may have been the case, but certainly not on early versions and perhaps it was always an extra-cost item. Driven by a 10 t.p.i. Acme-form thread, the spindle was marked with two scales: one at 1/16" and the 1/10" intervals - the latter able to be used as a form of vernier when used in conjunction with the handwheel micrometer dial. Unfortunately, with strong competition (especially from the Schaublin 102) the Boxford 4-inch precision cannot have been a success; the writer has encountered only two examples and, of the 2000 brochures printed, only one has come to light. If you have a Boxford precision lathe of this type, the writer would be very interested in hearing from you.
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