Page:Steamlocomotivec00ahrorich.djvu/83

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machine shops—axles and wheels
69

brass in the body of the box. The holes are then broached out for the pin, which secures the “keep” in the box. Following this the boxes are fixed to a long planed casting or angle plate on the bed of a planing machine, about twelve boxes, six on each side, and are planed on one face, and along the recess at the side which fits on to the hornblocks. The boxes are then reversed and the other face and recess planed. They are now bored four or six together on a special boring machine. In some works the boring and the facing are done together on a double boring mill, two boxes being machined at once. Oil grooves, which were formerly chipped out with a chisel, are now frequently grooved out on a small milling machine. Finally the fitters take the boxes and bed the brasses down on to the journals or dummies, by using red “marking” and filing down the high spots.