When purchasing a Mamod product people are not simply picking up a model that will be great in their own collection but they are investing in steam.

The UK is a pioneer of steam producing some of the most iconic locomotives to ever grace the railways. However, as diesel and electric trains replaced the glorious engines of a generation gone by it made many people unaware as how to a steam engine operates. Purchasing a Mamod product can reignite that passion and for those new modelling or even steam trains themselves it can be a great educational tool.

Mamod produces a range of fully functioning steam trains that can take pride of place in any collection but can also teach people about the workings of a steam. With a range including oscillating cylinders, double action oscillating cylinders and  slide vales, a Mamod steam engine represents a technology which changed the world as it was known and left behind the long standing horse and carriage.  

Here is a brief guide to the workings of these steam engines.

Piston steam engine

Piston steam engines are commonly used in locomotives and give these trains their unmistakable “choo-choo” sound. The engine consists of a double-acting engine with a slide valve which moves from left to right, this alternates which side of the piston the high-pressured steam is allowed. Depending on which side the cylinder will push the piston and also gives it forward and backward movement.

The valve rod and the cross-head are integral to the movement of a steam train as it allows the engineer to put it into reverse, highly important when shunting at works. The “choo-choo” sound, a characteristic of all steam trains, is made when the valve is opened to release exhaust steam under pressure. As a train comes to a halt, the piston slows right down, you can tell the speed of the train due to the frequency of “choo-choos“.


The boiler is integral in allowing high pressured steam into the engine and when it comes to running a steam engine either a fire tube boiler or a water tube boiler is essential. The fire-tube common was commonly used during the 1800s and produces hot gases which travel through pipes and heat the water. However, if the entire tank comes under pressure then it can explode.

As time progressed, so did the attitude towards boilers and the introduction of water-tube boilers heralded a new era for steam trains. The water version sees liquid run through a rack of tubes that are positioned in the hot gases from the fire. It allows to reduce the likelihood of an explosion and creates a boiler that is both efficient and reliable.

At Mamod, the company have slightly different designed boilers depending on the engine in questions. The first, and simplest, of the designs is a hollow brass boiler. The burning fuel is placed underneath the boiler where it will heat the water until steam acts on the cylinder systems. The second boiler design is as the first design but is equipped with copper piping which takes a small amount of water from the boiler over the burning fuel. This small amount of water heats quickly and is re-released into the boiler as steam. This system heats water faster as the burning fuel acts on the water in the boiler and the water being passed through the copper pipe.   

Mamod engines

Mamod sells a number of different models which also use varying engine types. If your interests lie with the slide valve engine type then look towards the Centurion, Samson, Brunel, Challenger and slide valve Marine engine. For a simpler type of engine, like the very popular traction engine, then look towards the wide range of oscillating valve engines types offered by the company.