This example from the Kleinemeier stable is inspired by the original Meccano engine.
The vertical boiler is 50mm diameter x 80mm and 80ml water capacity, fired by a burner holding two Esbit tablets. It has a water level overflow plug and a safety valve. There is a single flue through the centre of the boiler.
Steam is fed via a pipe which exits the boiler at the top. There are no throttle, lubricator or superheater and the pipe goes directly to the rear of the engine frame. Between here and the port face there is a reversing valve, which swaps the inlet and exhaust connections. The engine is a single cylinder single acting oscilating cylinder, horizontally mounted at the side of the heavy frame. Cylinder dimensions are (approx) 8mm bore x 20mm stroke. Exhaust steam is fed to the chimney.