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A stage beyond the usual third-party backgear systems sold for the Round Bed Drummond (and probably designed for use on a variety of lathes), the ingenious Walram attachment was bolted to the end of the headstock casting and driven from the normal countershaft by a flat belt. The unit, which allowed the spindle to be driven through either reduction or step-up gearing, also provided a means of powering the leadscrew and would have been able to generate an ultra-fine carriage feed. The fine feed was achieved by means of an additional compound reduction gear train where two gear, one large and one small, are pinned together on a common shaft. Normally the Round Bed (like most other lathes) would have been able to accommodate only two compounded gears but, with the Walram in place, three could be assembled. For example: with gears sets of 21/40, 20/63 and 20/64 in place a feed rate equal to 192 T.P.I. could be generated, far finer than that available with the standard set-up As the Walram employed the left-hand threading bracket as part of its mounting it could also be used to generate left-hand pitches and so was able to be left in place for all normal work..
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