The Locomotive Of Today

The Framing, Wheels, etc. : Hornblocks. 125 the road for the driver, he can be accommodated with a seat in a wide cab, built practically over the rear of the firebox. Returning to the engine plate frames, these are cut out to receive the hornblocks or axlebox guides, which are bedded down to them and secured as already mentioned. There are many patterns of such hornblocks, those now generally used being of cast Steel in preference to cast iron, but as the firm- ness and rigidity with which these are held to the frame is mainly dependent upon the bolts or rivets, it has been the practice with some makers to form them of wrought iron and weld them to the frames. With the separate castings it is customary to secure them with turned bolts or rivets, the latter hammered down cold. If bolts are employed it is best to rivet the threads at the outside of the nut, after the nut has been tightened up to prevent it from slackening back. A pattern suitable for coupled wheels is shown at A, Fig. 26. It has a flange surrounding the ledge which fits in the gap of the frame, and holes are drilled for the reception ot the holding bolts or rivets. On the side nearest the front ot the engine a face is formed from 5-in. to 6-in. in width at right angles to the frames and vertical. This face is carried up and over the top of the axlebox gap and down the other side, where it has an inclination of about 1 in 10 to the vertical with a wide groove cut in it for the reception of a similar projection upon a block or wedge, which has its other face vertical, and of an equal width to the fixed face opposite. These two upright faces enclose between them the axlebox, and any adjustment due to wear, etc., may be made by raising or lowering the wedge by means of the bolt shown carried down through the hornstay. This bolt is screwed into the wedge and turned by the square at the bottom. When the required position is found the screw is secured by the nut below the stay being locked. The wedge is prevented from leaving its place when being fitted or when the box is out of place by the stud or sunk headed bolt which passes through a slotted hole in the hornblock and has a nut upon its outer end. Oil holes are provided at the bridge across the top for supplying lubricant to the faces, and also to the axlebox bear- ing, pipes being often led from some handy place on the footplate. The hornstay passes across from one face to the other to stiffen the frame. In the particular example shown it also forms a bearing for the coiled springs to press against, these latter being placed upon long bolts reaching down from the axlebox. When so employed, one bolt upon either side is