Miniature Ringbom Engines is a practical introduction to a whole new branch of Stirling engine technology. The Ringbom engine is a hot air engine with a normal crank-coupled piston but with a displacer having no mechanical linkage. The free displacer is driven back and forth automatically by the changing pressure within the engine. This makes the Ringbom an utterly fascinating engine to see in operation and opens up a wide new world of possible configurations for engine designs. This first ever book on miniature Ringbom engines is primarily a how-to book, focused on presenting all the information needed for making good working model engines. Detailed plans and instructions for making three different types of Ringbom models are at the heart of the book. These comprise a tiny engine that runs at high speed on a small alcohol flame, a larger low temperature differential Ringbom which can run for hours on the thermal energy in a few cups of hot water, and an advanced single-cylinder Ringbom engine. The book starts by clearly explaining the basic principles behind Ringbom engine operation, and concludes with a chapter containing a large collection of new engine designs and ideas to explore. The author, Prof. James Senft pioneered the mathematical analysis and development of the modern form of the Ringbom engine.