Fig. 18
Fig. 19
If you decide to have the joints brazed you can get it done at the ironmonger’s, if you first cut out and fit the parts together and explain what you require. The floor of the boiler is made out of a piece of sheet copper nine inches long and seven and a half inches wide. Mark it as in [Fig. 18]. Bend it along the lines into the shape shown in [Fig. 19]. In the middle of the top make a hole one-third of an inch in diameter. Bore seven holes one-third of an inch in diameter along each of the sides and half way up. Cut a piece of the brass tube six and a half inches long, and braze one end of it into the hole in the top, as in [Fig. 19]. Cut seven pieces of the tube four and a half inches long each, and connect the holes on opposite sides by brazing the tubes across into the holes, as in the [figure]. Take the screw-block off the safety-valve and solder it over the hole marked D in [Fig. 13] on the inside of the boiler. Solder the screw-block of the steam-tap inside over the hole marked F, and solder on the inside the two blocks of the gauge-taps over the holes in the end of the boiler. The block of the man-hole must be brazed on the outside over the hole C, [Fig. 13].
Fig. 20
Now fit the floor of the boiler in its place, passing the end of the tube, fastened to the top of it, through the hole marked E in the top of the boiler, and projecting about half an inch, and braze it in. [Fig. 20] will show the position of the boiler floor. The top of it is to be two inches from the bottom of the sides. Braze it in firmly, being very careful to make all the joints steam-tight. Screw in the man-hole cover, safety-valve, steam-tap, and gauge-taps. On the top of the boiler and over the projecting pipe solder a piece of brass tube seven inches long and an inch and a quarter in diameter, raking aft a little, for the funnel. Now the boiler is finished and ready to be connected with the engine. But before this can be done we must make the reversing-gear.
Procure a block of brass, three-quarters of an inch wide, one inch long, and half an inch high. Square this up true, and bore a hole right through it from top to bottom, three-sixteenths of an inch in diameter. With the end of a rat-tailed file taper the hole to a little more than a quarter of an inch at the top. Get a piece of brass rod a little more than a quarter of an inch thick, and file one end of it taper to fit the hole, and square off the bottom end of it, making the taper portion half an inch long. Smoothen this with fine glasspaper, and then oil it and dust over it some fine emery-powder, and put it in the hole in the block and grind the two together till they fit perfectly. Cut the taper portion off exactly the length of the depth of the block.
