STEAM towards the gauges

I am on my first trip to one of the best places on the Great Western Railway. I have always wanted to travel to Swindon, as it is the central hub of the UK Space Agency and the home of the STEAM railway museum. If the National Railway Museum in York is the cultural celebration of the nation’s railways then STEAM is the celebration of a railway from Victorian times. It is here along this railway that Brunel’s contribution to the railways can be found. There is some very interesting stuff here.

Let’s start with what put this place on the map and in the interests of railing enthusiasts and museum geeks I am going to start with some basic facts. According to folk lore Brunel threw a sandwich outside of a speeding train and wherever it landed, which in this case was Swindon, that would be where the engine works would be built. Funny thing, but who’d believe that? The Swindon Works was established in 1856 and it’s the 175th anniversary of it’s birth. A number of famous locomotives of the Great Western Railway were built here. The site occupies over 326 acres and at the height of it’s heyday in 1956 it employed 14’000 people and could build 2 locomotives a year, repair 1000 engines a year, build 250 coaches, repairing 5000 carriages and 800 wagons were repaired here in a year.

Amongst the chief attractions here for the dodransbicentennial (175th) year are two very special locomotives. King George V, built in 1927 at these works and was the most powerful loco ever built by the GWR. The City of Truro was another great loco which has the same grand green appearance. Both of these machines were the pride of the line. STEAM reveals some interesting stories about the magical and broad history of the Great Western Railway and what made it so magnificent. It was all down to the splendid holidays you can get along the South Coast covering Exeter, Portsmouth, Penzance, Cornwall, Bristol, Bath and even Cardiff and Barry and other places in South Wales. I think I have been spending too much time exploring Scotland to not notice these places. I still have them on my list. Next time I go out to the Western line I’m heading to Cornwall and then onto Cardiff. I still need to see those Doctor Who exhibitions.

The GWR is the railway line that has a long association with royalty as well. It was the first line to experience rail travel by a head of state. As part of the Diamond Jubilee celebrations of Queen Victoria a Royal Saloon was built for which is on display in the museum. The pale green silk curtain holders are still there which held the blinds on the windows in place. The hand painted ceiling was flecking but original and the mahogany woodwork has aged beautifully. The GWR also provided a funeral service for four monarchs where their final journey was made on trains from Paddington to Windsor Castle.


Perhaps the most interesting part for me is the study of the gauges. I spent some time in York last year sharing my knowledge with my culture buddy Julia on the subject. When I arrived in Swindon I decided to make an investigation into the differences between the two gauges. Now when Brunel started the GWR he decided to build it to a much bigger size of track. Whereas Stephenson used the 4 foot 8 and half inch gauge, Brunel went for a whopping 7 feet and a quarter inch. It allowed for more spacious carriages and faster, steadier rides. But when you have two gauges on the national railway network it’s not good for logistics. When you go to a place from Bristol to Colchester via London you need to change into a different train and transfer all the cargo over in a turnaround that takes about 5 hours at a time. A terrible waste of travel time.

In 1946 a Royal Commission took action and decided to make the railways use one gauge. That way there would be no need for a turnaround. Of the 2175 miles of track across the country 1900 of it was using the Stephenson’s gauge. So the Commission decided to use his gauge of rail and this has now gone onto become recognised as the standard gauge. 60% of the world’s railways use Stephenson’s gauge. The process to convert the broad gauge to standard gauge took 18 years from 1874 to 1892. During that time of conversion a set of standard gauge rails was installed between the broad gauge rails.

What sets the two gauges apart in performance for the trains? Well Brunel built the GWR line  in places where there were no steep gradients and so that the trains didn’t need to climb a hill. A broad gauge train can not climb an inclination very well. Since the width of the train is so wide to allow for roomy carriages and heavy loaded wagons the weight and momentum of the train is spread out so the engine needs a lot of power to push itself up and cover a wide area. In physics this means that the load has a wide area of mass so it needs a lot more power to cover the body in order to pull itself up the hill. To achieve this the engine needs to produce a large amount of torque in order to make the wheels turn and those wheels need to be really big. This is why the early GWR broad gauge trains had such large wheels.

Stephenson’s smaller gauge was built to handle much of the northerly routes of the country and parts of the south. These areas and indeed most of the country had steep inclines, and twisting bends that could not be bypassed. For that the 4 ft, 8.5 gauge was more preferable. It concentrated the mass of the train towards the centre and could handle stability around corners. That way the engines didn’t need to be as powerful as the broad gauge trains and hence fuel economy was more reliable and cost-effective. The locomotives smaller size also meant that they were capable of faster speeds when concentrated into a smaller area of mass.

In some parts of the world smaller gauges work better more trains that transport people around mountain ranges. The Swiss use a metre wide gauge for their alpine services across the mountain range which are combined with a rack and pinion mechanism to improve traction. A broad gauge train would never be able to make that kind of ascent.

Right now time for some more exploration tomorrow when I go to see the Great Western Brick show. A display of Lego models of fantastic creations. I hope there will be some train models on display.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s