The spokes of the wheels should be painted; black-lined on green looks very well, and the ordinary tube oil-paint, mixed with a little mastic varnish, is the best to use.
The buffer-beam should be varnished, and the cylinders ought to have a coat of paint, leaving the cylinder-covers and the flanges bright.
Fig. 10.
The frame may now be put aside to dry, covered up from dust by a paper box, whilst we proceed to make the boiler ([Fig. 10]).
This is a most important part of the locomotive, and is the cause of a great many failures and unsatisfactory working, even amongst the professionally-built models. I well remember how, when a lad at school, I fell deeply in love with a beautiful highly-polished brass locomotive of about the size we are now building, which was displayed in an optician’s window. Having made inquiries about the price, and got it reduced from to £5 to £4, with a promise to keep it for me, I set to work to save my pocket-money, and for some months rigidly abstained from all kinds of tarts and toys; and when finally the last shilling was saved which completed the amount, and I carried it—my first model—home in triumph, no boy was ever happier. But, oh! the bitter disappointment when, after getting up the steam and trying to start the engine, I found it would not work.
I was too young then to find out the reason, and the man who kept the shop, not being a practical mechanic, could give me no help, and although, after we had tried it together, he offered to take it back, I decided to keep it with a view to remedy the defect, if possible; but it was a long time before I found out that the fault lay in the boiler not being able to supply sufficient steam for the cylinders, in consequence of not having enough heating surface acted on by the lamp.
Since that day I have made numerous models, and have always taken precautions to avert such a difficulty, and although the method I am about to describe entails a little extra work, you will feel well repaid for the trouble when you find what a splendid head of steam can be kept up.
The boiler should be eleven inches long by three inches and a half in diameter, and you can buy copper tubing of that size which is very suitable for the job, or you can form it from a sheet of copper or brass bent to shape round a wooden roller, and either riveted or soldered together. You must then turn two circles of brass about an eighth of an inch thick for the ends, and polish the outside of each nicely.
