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.
The whistle M will require a hole drilled for it to be screwed into, and that, as also the steam-tap N and water-tap O, can be bought cheap ready to put on, and is more satisfactory than making them yourself. But should you wish to do so, the method I have already described in Chapter X. of making an oil-cup applies equally to these.
The tap O should be screwed in at a slightly higher level than the top of box B, and when working the engine, should steam issue from it when turned on instead of water, you ought to immediately blow off steam by safety-valve H. Then unscrew K, and refill the boiler with water.
By this time the framework will no doubt be quite dry, and you can then clean and polish the boiler and attach it to the frame by a screw or solder at the forward end, and the steam-pipe N can be screwed on to the projecting piece of tube left at F, whilst you also screw a short length of pipe into the steam-box of engine through a hole in the bed-plate. Then bend it up to the steam-tap and solder them carefully in position; this will hold the after end of boiler firmly.