. Railway mechanical engineer . ndle machineis preferred on account of greater ease in clamping rods tothe table and the fact that the milling operation will be inplain sight; also it is not necessary to lift or lower the rodduring the milling as would be the case with a horizontalform of milling machine. As in the case of the grinder,heavy construction is necessary in order to support the weightof the rod and guard against the table binding, causing it towork hard during the milling operation. The operation of milling a rod, as performed in one ofthe larger railway shops, is shown in Fig. 2.
. Railway mechanical engineer . ndle machineis preferred on account of greater ease in clamping rods tothe table and the fact that the milling operation will be inplain sight; also it is not necessary to lift or lower the rodduring the milling as would be the case with a horizontalform of milling machine. As in the case of the grinder,heavy construction is necessary in order to support the weightof the rod and guard against the table binding, causing it towork hard during the milling operation. The operation of milling a rod, as performed in one ofthe larger railway shops, is shown in Fig. 2. It will benoticed that the rod is held on the milling machine table bytwo. clamps. Arrangements are made for easy leveling bymeans of two adjustable taper wedges on which the rod part of the rod extending past the table is held on atrestle, adjustable vertically by means of a screw and alsoprovided with a spring to compensate for slight irregularitiesin the rods. When placing a rod in the machine the following plan is. Fig. 2—Completion of Rod Milling Operation followed. The rod is placed in the two clamps with tire outerend resting on the trestle. The trestle is then adjusted tosupport about one-half the weight of the rod, side adjustingscrews being tightened to locate the rod on the center linewith the machine table. For rough adjusting, the operatorsights along the rod and table, but for more accurate work,the rod is lined with a surface gage making use of the sideof the table for guiding the surface gage. In order to insure the rod being set so that the top surfaceof the jaws will be parallel to the machine table, a spiritlevel is placed on the top of the rod jaw. The wedges of bothclamps are adjusted in or out as may be necessary until the rod is properly leveled. The hold-down clamps are nowplaced in position and tightened. If. as a result of tighteningthese clamps, the rod is thrown out of level, the hold-downclamps are loosened and the wedges again adjusted,
Size: 1684px × 1483px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectrailroadengineering
