Part one by Bob Middleton

Bob Middleton’s earlier single-cylinder Scotch Yoke engine described on MEWS was followed by a tandem version. The one shown above, displayed at Harrogate in 2013, was built by Brian Stephenson.  Bob allows his drawings to be put on MEWS. But he asks readers to bear in mind, that they were drawn for personal use rather than being published. He also points out that he has no formal training in design or engineering, and begs forgiveness for departures from standard practice. Bob actually started designing engines to while away the time on long sea voyages when he was captain on oil tankers. This week we have the first half of the drawings of Bob’s twin Scotch Yoke Engine (photo of his own model above). The drawings include some explanatory notes to help in making the components. All of these drawings can be downloaded for personal use - click on drawings.

Part two here.