Woodruff and Beach Steam Engine

| March/April 1992

Curator of Industry Henry Ford Museum Dearborn, Michigan 48121

Reprinted from 'Tools & Technology,' quarterly journal of the American Precision Museum in Windsor, Vermont.

Our museum building was constructed in 1846 for the manufacture of 10,000 Model 1841 U.S. Army rifles using only water power. In the course of doing this, they developed the most modern armory and machine shop in the country for precision interchangeable manufacturing. They also began to sell duplicates of the fine machine tools developed for their own use. This called for more power than making small rifle parts. As their business expanded, they found that the water power, always variable in quantity from a steady winter flow to the much reduced flow of mid-summer, interfered with keeping precise delivery dates. The only practical answer in that era was an auxiliary steam engine as a supplement, even though steam power was far more expensive than water power.

Many visitors to the museum inquire how the machinery was driven and about the water power obviously running over the dam. We have no exact date when the original steam engine was installed. A lithograph of 1849 shows no chimney or engine room, however, another lithograph of 1853 shows an engine room, chimney and open wood shed. Wood was the fuel of choice in the area at that time and later; the Central Vermont Railroad only changed to burning coal about 1900. As long as manufacturing continued in our building, until 1884, the fuel was wood and it is said that it was the cost of this fuel that was the major factor in discontinuance of the business. At that time the business was cotton manufacturing, a highly competitive enterprise.

For proper restoration and to meet public interest we have needed a suitable replacement for the original engine. Not many engines with the correct characteristics have survived, but a friend in Connecticut1 brought an engine of suitable age, size, quality, design and plausible origin2 to museum attention in 1982. An exciting feature of the engine found was the identification cast on the engine bed, 'Woodruff and Beach, Hartford, Conn. 1849.' Another wonderful and difficult to find feature was an engine that had a balance or flywheel with a narrow rim not used for a belt to drive the machinery. Instead the power from this engine, as with the original, was transferred from a coupling on the crankshaft to a clutch so that it could be coupled to the water wheel as needed or could also drive the factory alone, as circumstances dictated. The flywheel rim has not been machined and there is no evidence of balancing by the addition or subtraction of weight. Very probably the heavy crank was located on the light side of the wheel as a counter poise. The flywheel and crank, indeed all of the castings, are of excellent quality so the engine exhibits nice foundry work as well as superior skill in machine work.

One of the standard engine sizes made by Woodruff and Beach had a 14' bore and 30' stroke, to which our engine conforms. The maker rated this size of engine at 35 horsepower at 55 revolutions per minute. The steam pressure is not stated, but it is a high pressure engine of its era, perhaps however this amounted to not more than a boiler pressure of 85 pounds per square inch.3 The valve or steam chest extends the full length of the cylinder and is on the side rather than the top. This was a relatively new design at the time with two important features: it simplified the connection between the valve and the eccentric actuating it, and second, and very importantly, it made it easier for condensed water in a cold engine cylinder to escape to the exhaust pipe with much less danger of straining or lifting a cylinder head. The slide valve itself has a separate exhaust port at each end, thus steam was admitted to each end of the cylinder through a very short passage with a minimum loss of heat and pressure. Economy of the exhaust steam was a secondary consideration not much regarded at this time. Low pressure engines, particularly marine engines, did at this time exhaust into a condenser which increased efficiency, but it was chiefly done to reuse the water in oceangoing vessels to keep salt out of the boiler.