© M Goom 2006
This engine was produced to the design published by Philip Duclos in the USA Magazine Live Steam in 1991. Apart from the piston all parts are made from aluminium and hence it is a fairly straightforward model to make. However, it has virtually no power so it really is a model or toy purely for fun.!!
The principle of operation is very simple. The brass lamp burns methylated spirits to produce a small flame adjacent to the port on the side of the cylinder. On the "down" stroke the port is opened and the flame sucked into the cylinder. The slide valve then closes the port shutting off the flame in the cylinder thus causing a vacuum to develop. Atmospheric pressure acting on the base of the piston completes the rotation. The fact the flame is drawn into the cylinder justifies this type of engine being included under the "internal combustion" title. The engine emits a characteristic "phut" "phut" when operating due to the action of the vacuum forcing the slide valve onto its seating. Engine speed is "regulated" by varying the position of the flame relative to the port. The performance of the engine is very dependent upon the "strength or fierceness" of the flame, if too fierce then it seems to be reluctant to enter the port and hence gives poor starting and short running duration.
An excellent project if you want to develop your machining skills and produce something that is both different from the usual run of the mill and which actually works!!