Close up of the Corliss valve gear linkages connected from the centre rod to a triple eccentric on the crank shaft.

The model is built from mid nineteen fifties red and green with the additional use of zinc plated parts and 16 replica channel segments. It is driven by a 12 volt non Meccano motor located in the base driving the crank shaft though reduction gears and belts. Above is a close up showing crank arm, bearings and connecting rod. Each spoke of the flywheel is built up from six 9 hole strips. The governor driven by a rubber drive belt is shown on the right.

Click in the YouTube logo below to see a video of the engine in action.

The Corliss steam engine is a type of engine, fitted with rotary valves and variable valve timing patented in 1849 and invented by the American engineer George Henry Corliss of Rhode Island. The use of the rotary valves increased the fuel efficiency of these engines by around 30% over earlier types. Engines of this type would have been used in mills and factories driving machinery through line shaftings other uses included power generation and driving water pumps. There is a fine example preserved at the Pump House Steam Museum Kingston Ontario shown above but unfortunately cannot be steamed.

I have long been fascinated by the Corliss valve mechanism ever since I saw the instructions for the Meccano Mill Engine in an instruction manual of the early nineteen thirties. Although that model demonstrates well the principles of the valve gear the model does not seem to be very representative of any actual engine.

I came across several examples of Corliss engines in Ontario during my visit in 2014 it was after seeing these I decided to build a model of one of these engines. In addition to my own pictures I found several diagrams and engravings on the web to aid my building. An example built by "Bates" around 1905 has formed the basis for my model. I have not attempted to build the rotating valves just the linkages that activate them. I was looking to achieve an aesthetically pleasing model rather than an accurate scale model the latter being in any case beyond my building capabilities!

Page created March 11 2015 Revised April 25 2015