US Shay Design Gear Drive Steam Locomotive

The Industrial Age also marked the beginning in the USA of systematic development of natural resources which provided the material for rapid progress. Coal became the most important source of energy and wood was needed in large quantities for the construction boom across the country. However, there were many extensive forest areas and also large coal deposits often in remote regions that were difficult to access. The sawmill owner Ephraim Shay developed a gear-driven steam locomotive around 1873 in order to open these areas up better. Its design allowed it to pull heavy loads on difficult, curving routes. At high speeds it could not manage the job. Starting in 1880 the large locomotive builder LIMA Locomotive Works took over its construction and continuously refined it. The basic principle remained the same: A vertically installed steam engine mounted on the right side drove all the axles using a gear drive and thereby provided optimal pulling power, whereby the boiler had to be mounted offset to balance the weight distribution. The maximum speed was limited to about 25 km/h / 15 mph due to the small gear reduction. The Shays turned out very well and became a mystique among steam locomotives not only due to their unusual technology but also because of their massive appearance. In the end, a respectable 2,770 Shay locomotives were built by 1945. Most ran on forest logging railroads, although a number of units were also delivered to important railroad companies. The Western Maryland Railway (WM), developing the numerous coal reserves in the eastern part of the USA, bought large Shays for branch lines to coal mines. There grades of up to 10% and curves of under 100 meters / 325 feet had to be mastered. By 1945 the WM used the massive, 136 ton four-truck Shay Number 5 in the Appalachians. It was replaced by the most powerful Shay ever built, Number 6, which still currently steams through the mountains of West Virginia in tourist service. The new Märklin Shay is entering the fascinating world of model railroading with this quite unusual chapter in locomotive history.