From the book description:
A highly illustrated, step-by-step guide to constructing a range of simple model steam engines, aimed at both beginners and the more experienced. This book details the construction of a range of simple miniature steam engines and boilers. The projects, each of which can be completed with only a basic workshop, range from a single-acting oscillator to more sophisticated twin-cylinder double-acting engines and a variety of boilers. A final project brings together engine and boiler for a simple steam railway locomotive. These projects are a perfect introduction to model engineering and an enjoyable exercise for the more experienced engineer or those who wish to pass on their hobby to a younger generation.
Here is a link to the book Making Simple Model Steam Engines.