D Brimacombe



The Robinson hot tube engine (not to be confused with their hot air engine) still creates interest among engine builders, even though castings are no longer available (unlike the hot air engine). This is the famous ‘chippy’ engine, so-called because of its popularity with fish and chip producers. Robinson was a supplier to the catering industry. Although castings are no longer available from the Alyn Foundry, enterprising model engineers are starting to build from bar stock. 

The hot tube engine is a relative of the hot bulb engine with better timing control. The hot bulb engine only ran well at one speed - and a low one at that, typically 100 RPM. Timing of a hot tube engine is controlled by varying the length of the hot tube ignitor, which is longer and thinner than the hot bulb on a hot bulb engine. Length of the tube controls when the charge ignites, different operating speeds can be selected. Hot tube and hot bulb engines were precursors of the diesel engine.

This model was shown at Doncaster in 2017 by D Brimacombe.


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