The wheels, Figs. 91, 94, p. 88, after being annealed and dressed up, come into the shop with the gits on. They are "chucked" by the aid of ordinary dogs to the face plate, and this git is removed by a parting tool, which is made from bar steel 3 inches deep, ⅝ inch wide at the top, and « inch at the bottom, jumped up to ⅞ inch wide at the cutting edge. While thus fixed they are rough turned all over, including the wheel seat, "topping" on the tread, and also the sides of the balance weight. They are then re-annealed, and the wheel seat is bored to the standard size and pressed on to the axle. The pair are then turned to gauge for the tires, the speed varying from 16 feet to 18 feet per minute. Fig. 287 shows an extremely handy chuck for wheels of small diameter, say bogie, etc, which is attached to the ordinary face plate. The drivers are represented at A, the bearings for the spokes at B, and adjustment under the rim at C, This arrangement admits of the following operations being performed during the one setting: boring the boss or wheel seat, turning the tread, and facing upon each side of the rim.

The crank pin seatings are then bored out at a quarter-centre boring machine, parallel and both at once. This machine consists essentially of two headstocks, fixed upon one bed at a suitable distance apart, and in each is the gearing for driving the boring bar. The wheels and axle are placed between the centres, one crank pin seating below in a vertical centre line, the other seating will then be either leading or trailing. Between the wheels are two other standards or frames, for supporting the other end of the boring bar in a pedestal; this for the vertical seating is simply arranged for upward or downward traverse only, whereas the opposite can be transferred as required, leading or trailing, with a certain range of horizontal traverse, the boring bar being also capable of similar rearrangement. The wheels are now ready for the tires, which have been bored and grooved to template at 10 feet to 20 feet per minute. These are put on by expanding, Bunsen jets being the heating medium employed, which is simply a perforated tube encircling the tire, and giving to the whole a very uniform heat. The ⅞ inch tapping holes are then drilled through the rim for the securing bolts by a double-headed drilling machine, a smaller hole being drilled into the tire 1« inch deep for the end of the act screw, it being turned down accordingly.

Fig. 287.

Scale 3/4" = 1 Foot.

The cylinders - Figs. 53-60, p. 50 - are first placed on the setting-out table, centre lines drawn, and the whole casting checked over. They are then placed on the planing machine, bottom upwards, set to the centre lines, and the edge upon each side is planed. The tool is then set to a 2-inch gauge from this edge, and the drain cock nipples planed up, which afterwards act as the foundation for the setting for future machine work. The front end is then planed to gauge, from the centre of the steam ports to the face, also at the same setting the angles for the smoke-box tube plate and the door plate are cut, the cylinders being fixed at the required angle, or canted, if they are so placed between the frames. They are then planed upon each side at one operation, for the frame seating, to standard width, the same setting being also utilised for machining the port face and the smoke-box steam chest cover face. The planing operation on each is one good sliding cut, with a tool having a large curved point, broad shavings being removed with a good surface finish, at from 18 to 20 feet per minute. The next operation is to fix them upon a table, which is on the floor level, within a jacket of standard width, which is really the frame of a machine carrying four boring bars, pitched out exactly to the centre of the piston and valve rods, which enables the stuffing-boxes to be bored out at one operation, without any setting whatever.

The boring mill is arranged very similarly, each cylinder being bored simultaneously at 11 feet per minute, with 1/16 inch feed for roughing, and ⅛ inch finishing per revolution. They are then ready for the steam and exhaust ports, and the bearings for the guide bars to he either slotted or milled to width or thickness. At the drilling machine the drain cock holes are the first drilled, and then the bolt holes for securing to the frames. These holes are 1⅛ inch standard, and are drilled through a jacket, which is simply a cast-iron plate with standard bushed holes, the whole arrangement being set at once by lugs, which are cast on to the plate, coming flush up against previously machined portions of the cylinder, whereas the jacket for the steam chest cover studs has centre lines, which are set to those on the cylinder and then cramped. Fig. 288 shows the drilling jacket for the holes in the guide bar brackets at the cylinder end. The stud holes are drilled, tapped and studded by a lightning tapper, at 160 revolutions per minute, with 1« inch downward traverse per minute, the steam pipe holes and seatings being bored out at the same setting. They then pass on to the cylinder fitters, all covers are adjusted, glands put in, valves and spindles tried, and all nuts put on, those outside being case-hardened, and those in the smoke-box being brass box nuts.

Fig. 289. Scale 3/4"= l.0.