. Railway mechanical engineer . resistance against strain. The top wall is solid,the cross feed screw being located in a shallow depressionmidwav between the saddle Vees. The table is IS in. wide with a working length of 72 in. The gibs in the saddle andtable are of the adjustable taper type. The over arm is a solid steel bar 534 . in diameter, witha wedge lock which positively locates the pendants andalines the arbor, thus preventing any tendency to twist outof line under heavy cuts. The outboard support is of theopen side type developed by this compan\-, permitting freeaccess to the table an
. Railway mechanical engineer . resistance against strain. The top wall is solid,the cross feed screw being located in a shallow depressionmidwav between the saddle Vees. The table is IS in. wide with a working length of 72 in. The gibs in the saddle andtable are of the adjustable taper type. The over arm is a solid steel bar 534 . in diameter, witha wedge lock which positively locates the pendants andalines the arbor, thus preventing any tendency to twist outof line under heavy cuts. The outboard support is of theopen side type developed by this compan\-, permitting freeaccess to the table and the work at all times. It is reversibleto bring the open space on either side as required. The spindle is large in diameter and runs in adjustablephosphor bronze bearings. All other shafts in the speedtransmission run on ball bearings. The driving force isapplied to the spindle on a face gear which overhangs thefront bearing, thus reducing the torsional strain in thespindle. .As the face gear is the only slow speed member in. Feed Change Gears and Case. Showing Unit Construction the driving train, chatter is practically eliminated andthe drive is smooth under heavy cuts. The speed changes aresecured through a train of gears giving 18 spindle speedsranging from 14 to 350 r. p. m. All speed changes aresecured by sliding gears and there are never more than threepairs of gears in mesh. The normal direction of spindlerotation is right hand w-hich makes it correct for standarddrills and boring tools. A spindle reverse has been incorpo-rated in the machine, for, in order to get the cutting strainsin the proper direction on the gibs and the tables, the facemills must run in the opposite direction from the spiral orslab millers. The principle of unit construction has been used to a con-siderable in the design, thus .securing manv advantagesboth in manufacturing and in repairing. The spindle speedchange mechanism is an integral part mounted in a box se- 161 162 RAILWAY MECHANIC
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectrailroadengineering
