The book Miniature Ringbom Engines is a practial 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 free of any mechanical linkage. The displacer is driven automatically by 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 Stirling engines. This first ever book on miniature Ringbom engines is primarily a how-to book, focused on presenting information and ideas for making working engines. Detailed plans and instrucitons for making three different model Ringbom engines are at the core. These include a tiny engine that runs at high speed on a small flame, and a larger Ringbom which can run for hours on the thermal energy in a few cups of hot water. The book starts with the basic theory behind all Ringboms, and finishes with an advanced engine design and a large collection of new engine ideas to explore.

The author James R. Senft is a universtiy professor who has written and lectured extensively on Stirling engines, and served as consultant to universities, laboratories and industrial organizations working on engine development. Dr. Senft is especially noted for having pioneered the mathematical analysis and development of the modern form of the Ringborn engine.