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Illustrated on this page are Greaves-Klusman lathes manufactured during the first twenty five years of the 20th century by the Greaves-Klusman Tool Co. of Cincinnati, Ohio. These were all no-nonsense machines, very heavily built for their size and incorporating many features to help the operator rather than save the manufacturer money. The entire range, from smallest to largest, shared the same basic design and constructional details. Massively built, the headstock had heavy webs running along its entire length and between and up to the center line of the bearing housings. The line between headstock and tailstock centers was placed back from the center line of the bed which, in combination with a low-set V at the rear of the bed, was designed - claimed the makers - to keep the angle of the tool pressure within the front V when turning large diameters. Some models had the sophistication of a double-reduction backgear--a necessary adjunct to getting a decent performance of a flat-belt drive system. Combined with the 3-step pulley nine speeds were available from approximately 15 to 450 r.p.m., a very typical range for lathe of this size at the time The backgear assembly was carried on an eccentric shaft in the normal manner, with the two-speed gears in mesh together, but loose on the shaft. Engagement was by two cone clutches operated by a yoke attached to a vertical lever. This tall lever (about 2' 6" long) was pivoted behind the headstock with a long horizontal bar from its top to a matching upright lever at the tailstock end, thus allowing speed changes to be made by the operator anywhere along the length of a long-bed machine. There was no neutral, the lever arm assembly being heavy it "flopped" from side to side, its weight holding the cone clutch in place. Operators report that it would select the high or low ratio without noise or protest no matter how fast the belt pulley was running - and the drive never slipped. Although it was possible to hold it in a mid position by hand to stop the lathe, this was not considered a safe procedure. This unusual speed-changing feature only worked with the backgear engaged, direct drive by belt being entirely conventional. It was possible to face large diameters by starting in low gear then switching to high as the diameter reduced sufficiently - a feature much appreciated on piece work. Of high-carbon, hammered crucible steel, the headstock spindle ran in hardened front and rear alloy-bronze bearings - with the end thrust absorbed by three collars, one each of bronze, steel and cast iron. The spindle fittings on the 22-inch, 24-inch and 30-inch lathes were identical - as were those of the 24-inch and 30-inch models - allowing chucks and faceplates to be interchanged between lathes in each group. Clamped to the bed by four short, heavy bolts, all of which were accessible from the front of the machine, the tailstock was further protected from creep under very heavy loads by a pawl that engaged with a rack cut in a double-walled, stiffening brace that ran down the center of the bed. The tailstock spindle was of the "Greaves-patent" type. as illustrated and described in a booklet called "G-K Betterments" - does anybody have a copy ? Constructed with double wails, the apron had all shafts supported at both ends, but unusual in that, once the control handles had been detached, the front part could be removed and the mechanism cleaned, adjusted and lubricated as necessary. All the gears were properly cut from steel and ran on hardened and ground studs. The power cross feed was engaged through a clutch and arranged so that, should the cross slide be driven right to the end of its travel and strike the saddle, the device would slip and save the gears and shafts from damage. Adjustable stops were provided to disengage the power-sliding feed of the carriage in both directions - which was driven not from the leadscrew, but by a separate power shaft carried below and parallel to it. The drive was taken from the shaft by a double-bevel pinion, supported in a bronze-bushed bearing whose housing was cast solid with the main apron casting and not bolted to it - as on many cheaper lathes. The lathe followed well established contemporary practice and carried the mechanism for reversing the longitudinal and cross feeds are inside the apron, and not on the headstock. Continued below -
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