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Manufactured from the late 1940s until the early 1960s - the last example leaving the Biggleswade works in June 1961 - like the better-known and very successful Boxford, the 4.75" x 18" Smart & Brown "Sabel", SAB and S were all copies of the South Bend 9-inch "Workshop" lathe. However, rather oddly, the Smart & Brown version used a different arrangement of the bed ways, the back of the saddle running on a flat instead of a V-way. Named after the maker's factory "Sabel", in comparison with the original South Bend, the Smart & Brown was built to a much higher standard and was, as a consequence, rather expensive. The headstock was better guarded (somewhat along the lines of the contemporary South Bend "Light Ten" also from the same era) together with a re-designed spindle assembly, larger bearings, a fractionally larger bore and the nose thread increased from 1.5" x 8 t.p.i. to 1.75" x 8 t.p.i. Lubrication of the spindle bearings was by wick from small reservoirs beneath each bearing, filler plugs (usually by "Springwell", being positioned at each end of the flat surface against which the headstock belt cover rested. A point to note: on the left-hand end of the spindle, to adjust the end float, is a screw-on ring locked by a grub screw. The ring has a shallow recess on one face and this must face inwards; placed the wrong way round it is not possible to take up the end float and a gap is left. Also improved was the cross-feed screw, this being increased in diameter to 1/2" and a modification that promised a much longer life and gave a somewhat better feel. Offered as an accessory, was a rather large sheet-metal cabinet stand with a superbly made - if rather over-deep - aluminium countershaft unit that was available in two forms: with 8 speeds from 45 to 595 r.p.m. or 16 speeds from 45 to 1200 r.p.m. - the latter (with 2-step pulleys on motor and countershaft) being by far the more common. Another option listed by the makers, though one never seen by the writer, was a flat-belt overhead drive with 6 speeds from 41 to 658 r.p.m. In addition to the "Sabel" version, the lathe was available, like the South Bend original (and many other clones), in two other models: one, the "SAB" (equivalent to the South Bend Model B) lost the screwcutting gearbox but retained the power-feed apron (the mechanism for which provided not only power cross feed but also a rate of sliding feed very much slower than could be obtained by just the changewheels) while the other version, the "S" (in line with the South Bend Model C), was fitted with a plain, hand-feed apron. Screwcutting ranges and rates of feed were identical to the equivalent South Bend and Boxford models, the "Sabel" producing 48 pitches from 4 to 224 t.p.i. With sliding and surfacing feeds being, respectively, 0.0853" to 0.0015" and 0.0256" to 0.0004". The changewheel models, the "SAB" and "S" both gave 45 pitches from 4 to 160 t.p.i. but as the SAB retained the power-feed apron its feed rates were identical to those on the "Sabel" with the "S" (no power cross feed) having sliding rates of 0.0155" to 0.0021". Both the "SAB" and "S" are seldom found and must have sold in very limited numbers. As two examples of wonderful attention to detail (although some spoilt-sports would call it wasteful over-engineering) instead of just bolting the ordinary Dewhurst electrical reversing switch to the face of the stand it was mounted on the headstock - but tucked away at the back and operated by a cross shaft from a chrome-plated lever (in bronze) mounted on the front face. To guild the lily, the end of the cross shaft carried a large gear, also in bronze, that engaged with another, smaller (bronze) gear fastened to the end of the switch spindle. The headstock cover was prevented from falling backwards not by the late 20th century method of a simple strap retained by self-tapping screws, but by very much more complex and altogether more expensive arrangement: - a wire passing through threaded retainers screwed into a cylinder cast integrally with the cover and, at the other end, a tapped hole bored vertically into the headstock casting. Another development of the South Bend 9-inch was also manufactured by Smart & Brown, the very rare Type 918. With a capacity of 4.5" x 24", this version was mounted on an improved welded sheet-steel cabinet stand (braced with angle iron) that housed an under-drive system with the motor fitted to a countershaft similar to that used on the Company's Model A lathe. To aid smooth running, the headstock V-belts of the Sable were replaced by a 3-speed flat-belt drive and the lathe improved in several areas: a roller bearing headstock, large micrometer dials, a tailstock with a cam-lever locking arrangement, feet cast as part of the (deeper) bed and a much more rugged top slide. Although spares are no longer available for this range of Smart & Brown lathes, many Boxford and South Bend parts and accessories will fit or can be modified (including the T-slotted cross slide) so providing a cheap and easy route to restoration. These, and one-off parts can be obtained from lathes.co.uk Serial Numbers. Ikt appears that as machines left the works they were numbered in turn regardless of the model type. The surviving serial numbers for the Sabel SAB and S are: 1949….. 4903 1952….. 6550 1955….. 8385 1958….. 9562 For more details of the original South Bend model click here. If any reader has a Sabel, SAB, C or 918 in fine, original condition, the writer would be interested to hear from you...
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