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Continued: Hardened and ground, the threaded nose of the headstock spindle (with either a 1.125" x 12 t.p.i or M27 DIN 800 thread) carried a No. 2 Morse taper and was bored through 9/16" and ran on taper roller bearings. The motor was fastened to the back of the headstock (making a self-contained unit) and drove, via a jockey pulley, to an overhung pulley on the end of the spindle with the arrangement proving seven speeds 110 through 250, 360, 550, 820, 1100 to a useful maximum of 1700 rpm. All speeds were belt driven and a proper backgear sacrificed in favour of allowing the spindle to be slid in and out of the casting to give a quill feed travel of 1.75 inches - necessary when mounted vertically and used as a milling and drilling machine. A disadvantage of this arrangement was the bottom speed of 110 rpm, a rate that would have cautioned all but the most experienced of amateur owners against screwcutting or attempting to turn large diameters on a faceplate. The adaptation to vertical milling involved unbolting the headstock and motor unit and fastening it to a replica of the lathe bed that bolted to a substantial cast-iron bracket at the rear of the "bed proper". Unfortunately, no screw-feed was provided to move the head up and down the column and coarse settings involved bolting and unbolting the unit while supporting and moving it by hand. Tumble-reverse was fitted to the changewheel drive though, strangely, screwcutting gears were charged as an extra, at least for the UK market, and no screwcutting gearbox was listed. However, to compensate, the lathe did have the advantage, unusual in so small a machine, of a very fine feed to the carriage by a belt drive from headstock spindle to a 2-speed gearbox on the end of the leadscrew. A standard and very useful fitting was a graduated handwheel on the leadscrew end. By 1962 the angular-styled Mk. 3 "Series 3000" was in production and being sold in three versions. The best was the MQ-3100, with a full screwcutting and feeds gearbox and equipped with two headstock-motor units - so it was always ready for vertical milling and drilling. A cheaper version, the cheaper M-3100, was mechanically identical - and with two headstocks - but with changewheels for screwcutting. The entry-level model, the M-3000, came with changewheels and only one headstock that had to be shared between lathe and milling column. Unchanged at 9/16" bore and with a No. 2 Morse taper centre the spindle nose was hardened and carried either a 1.125" or M27 spindle nose. However, on the better-specified lathes supplied with a non-sliding quill assembly in the lathe headstock (i.e. the "Maximat Compact" with a powered milling head in place) there was more room in the casting and they were equipped with a larger assembly carrying either a 1.5" x 8 t.p.i or M4 x 39 metric nose, a No. 3 Morse taper and a 20 mm (3/4") bore with an adaptor fitting to accept ordinary draw-in L20 collets. In all cases the spindle now ran in a Class 7, double-row roller bearing at the front and two Class 7 angular-contact (ball) bearings at the rear while the overhung pulley that drove the spindle ran on two angular-contact ball bearings. However, variations on this theme have been discovered, and it is entirely possible that not only were lathes originally supplied with a vertical-milling head (MQ-3100 and M3100) fitted with a "lathe" headstock that lacked the sliding quill mechanism, but the headstock supplied for milling was altered to accept collets similar to the ER type, which had a much better grip on milling cutters. With the new headstock, spindle speeds dropped in number from seven to six and, with a 1725 rpm, 0.5 hp 1-phase (or 3-phase) motor, these were: 125, 210, 370, 620, 1100 and 1900 rpm. Alternatively, a slower single or three-phase 0.5 hp, 1120 r.p.m. motor could be ordered to give: 80, 140, 250, 420, 720 and 1250 r.p.m. Again, variations from the catalogue specification have been found amongst production machines with some examples using a 1/2 h.p. split-phase, single-phase motor (fitted with a 560 mf start capacitor and a 40 mf run capacitor) on both the lathe and milling head. Of the two speed ranges, the slower 80 to 1250 rpm would have been the better for both screwcutting and large-diameter turning - if still nearly 100% too fast on the bottom speed for comfort and safety. However, in later versions of the Maximat (the much better known V10 and V10P Models) things were considerably improved with the employment of an all-geared headstock driven as standard by a 2-speed motor - in addition to being fitted with the 4 or 6-speed all-geared milling head from, respectively, the U2 and FB2 millers. Fitted with 2 T-slots arranged to run at a right-angle to the bed ways the robust 10" x 4.75" cross slide was adapted from that on the Mk. 2 and retained the feature whereby the top slide could be slid backwards and forwards in the slots and bolted down in any position - this part of the design continuing unaltered on the V10 series in later years. Able to generate 24 threads and feeds, the Norton-type screwcutting gearbox featured the standard controls of a sliding tumbler lever on the front, a three-position lever on the top and a push/pull knob sticking out of the end cover to select either screwcutting or fine feeds for sliding and surfacing. As an indication of the quality of the lathe, the screwcutting gearbox was fitted throughout with ball bearings and the leadscrew (0.75" x 8 t.p.i Acme form) was both hardened and ground and could be adjusted so that it was tensioned between the angular-contact ball bearing in its support brackets. Although models equipped with screwcutting by changewheels had an entirely adequate range of fine feeds, Emco persisted in fitted a modified version of the original belt-drive 2-speed feed gearbox. Based on designs commonly employed from the late 1800s until the 1920s, the new box held an expensive ratio-lowering worm-and-wheel assembly together a pair of bevel gears to turn the drive through 90-degrees. Just before sales of the entirely new V10 range began a Mk. 4 version was introduced as the two-model 4000-Series - again, a machine rare in the UK but one that met with some success in the USA when sold through the Edelstall Corporation. Modifications over the Series 3000 appear to have been few (though the headstock was modified to take a No. 3 Morse taper) with the Model 4100 having a screwcutting gearbox and the 4000 screwcutting with changewheels - both models being supplied with two headstocks as standard. All-metric versions - gearbox, leadscrew and compound slide rest screws and micrometer collars - were given a suffix M, as in 4100-M. Additional features offered as extras on these later-model machines included a choice of a single-speed 1120 or 1725 r.p.m. motor (U.S.A. specification) - that gave top speeds of 2250 and 3400 r.p.m respectively - and a more sophisticated SCR electronic unit that gave variable-speed control of the spindle from 0 to 35000 rpm and with instant reverse. A useful variable-speed electric motor and gearbox unit was also available to drive the carriage and so allow the optimum sliding speed to be obtained for virtually any job. Tony Griffiths
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