Steam engines are intricate devices and require a lot of painstaking work to ensure they are put together properly.

Mamod has been able to incorporate these engines into its various models whether it be on the road, rail or water. They can range from the simple single cylinder, single acting oscillator to the more complex slide valve engine and, depending on the collector's preference, can be a real interesting addition to their array of models. Before starting, however, people need to be aware of what makes these engines tick to successfully implement them.

For example, while Mamod does not actually supply single cylinder, single acting oscillator engines anymore, they are the simplest configuration on the market. The cylinder oscillates from side to side opening and closing the port for the supply steam and exhausts. It does not start up on its own or reverse making it the ideal engine for a boat.

This is just one of the engines that are applicable for steam models. Here are others currently supplied by Mamod.

Twin, double acting oscillator

A step up from the single cylinder engine, the twin, double acting oscillator is a more common arrangement than its predecessor. This engine is different because it is sealed meaning the steam can act above and below the piston, giving it the double acting name. The cylinders are also arranged differently in order for there to be always one on a power stroke.

Unlike the single engine, the double is adaptable and can self-start and is also reversible making it ideal for either a road or rail-based model. However, the arrangement of the cylinders, either horizontally opposed or in a V-shape, mean that with the right craftsmanship it could be implemented and fixed onto a boat.

While they can use much more steam than the single version, they are robust engines as well as being simple to operate, reliable and relatively high revving.

Slide valve engine

The slide valve engine continues to be a popular product within Mamod's portfolio and is used in models both stationary and non-stationary. It is a much different configuration than the likes of the oscillating engine, providing a much different motion. The arrangement contains a fixed cylinder with the piston moving up and down and a more normal conrod which is found in a petrol engine.

Steam enters the chest of the engine and is then directed by the sliding valve which then supplies or exhausts the cylinder space. The valve is also connected through another conrod to an eccentric on the crankshaft. One of the main selling points to the slide valve engine is the fact there no steam lost at the port faces, which can happen in an oscillator. The steam inlet and outlet can be timed allowing for a much better performance.

Another characteristic of the slide valve engine is that the valve can be adjusted to release steam at just the right time in the cycle. This allows for people to dictate how they want their model run and gives them much more power over their model.