The box can now be placed in the boiler through the slot cut in the bottom, taking care that the top of box is not more than half way up the boiler, as in B ([Fig. 10]). This will leave a portion projecting below the lower edge of boiler, like C. This part protects the flame of the lamp from being blown away by the draught caused by travelling along, which would cause you to lose steam. Solder it firmly in position from the outside, to prevent the flame touching any soldered portion. Also solder neatly round A ([Fig. 10]).
Fig. 17.
The chimney can be made from another piece of three-quarter brass tube. Chuck it in the lathe, and turn it up bright, and put a collar on it at A ([Fig. 17]) to allow it to push on to the piece of tube left projecting at A ([Fig. 10]).
The top of chimney, or bell-mouth, B ([Fig. 17]), will require turning in the lathe also, and fitting on neatly.
The steam-chest D ([Fig. 10]) is a brass casting you can turn up also, and after cutting a circular hole in top of boiler of about an inch in diameter it can be either screwed or soldered on, previously putting the steam-pipe E in position by drilling a hole at F, and after bending it as shown, pass it through at F and solder in place.
The top of pipe E should be about a quarter of an inch from top of inside of steam-chest.
Before soldering on the steam chest drill a couple of holes, as at G H ([Fig. 10]), one for the small lug G to be screwed into, which holds one end of the lever of the safety valve, and that at H should be drilled conical with a rhymer, and the valve H can be turned in the lathe, and afterwards ground to fit the hole with a little emery and water, by means of a slot cut across the top and worked round with a screw-driver.
The spring-case of safety-valve is easily made from a piece of the one-eighth of an inch brass tubing, and using some small, hard brass wire to form the spring of. When finished it should be hooked to the eye screwed into boiler at V.
The manhole, or screwhead, K, is used to refill the boiler by when it has steamed low, and will require to be turned up to shape; and the bed L it screws into can be firmly soldered on the boiler, having first drilled a hole slightly larger than the diameter of the screw itself, which should be sufficiently large to allow an ordinary tin funnel to be used to refill by, and the screw ought to be large enough to hold a leather washer under the head to keep it steam-tight.