Bob – the engine, boiler and all associated ‘gubbins’ were designed and built by myself (although following a well-trodden path). The ship has been steamed several times and performs very well on the water under full radio control. She always attracts a lot of attention at my local boating lake, especially with children (more so when I sound the whistle!). The power plant picture shows the engine as originally built, with a boiler feed pump that was intended to draw water from tanks on board the ship – this facility has been discontinued to reduce the weight.
The engine is a parallel twin, double-acting oscillating engine of 10mm bore x 11mm stroke, operating at about 12-15PSI, geared around 10:1 to the paddle shaft via a primary gear reduction and a secondary chain drive, giving somewhere close to scale speed at full regulator.