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How do I glue balsa wood?
Posted in: Assembling and gluing, Best practices
17th July 2019
That would very much depend on what it is you are trying to glue the balsa wood to, if you are gluing it to another...
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What is an A1A-A1A wheel arrangement?
Posted in: Rolling stock
22nd November 2021
In the UK, an A1A-A1A wheel arrangement was used on some early designs of diesel railway locomotives, most notably...
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How to fit drivers in locomotives
Posted in: Model Railway, Best practices
26th November 2020
Installing a driver or fireman into your locomotive can really bring it to life and add realism. After all, in real...
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Do cambers help model trains traverse a bend?
Posted in: Tracks
23rd May 2022
In real life, railway tracks tilt slightly as they negotiate curves. The tilt is known by many names, including a...
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Is modelling in N gauge cheaper than OO gauge?
Posted in: Model Railway, Rolling stock, Scenery
27th May 2020
Although N gauge is very popular (and for good reason), it can't be denied that the most popular gauge on the UK...
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What are vacuum pipes for?

Vacuum pipes can be seen on the front and rear of many older railway locomotives and rolling stock. They are usually located either on or around the buffer beam and are used to provide a 'through' vacuum to operate the train's braking system.

Vacuum brakes were introduced in the 1860s. Before then, trains were braked using a basic handbrake system which was slow to apply and required a member of railway staff per wagon. Needless to say, that setup meant accidents were commonplace and a more sophisticated system was needed.

Using vacuum as the power to operate individual brake cylinders was a natural choice as the ejectors (already used on steam locomotives) can be used to generate vacuum without complicated or moving parts. The vacuum pipes on the ends of locos, wagons and coaches are connected when a train is marshalled to provide a vacuum supply to all of the brakes throughout a train.

Although the new system now gave drivers the ability to apply the brakes to a whole train with the use of a single valve, it still required the locomotive to be attached and operational to operate. That was a problem as coupling breakages were commonplace back then and a runaway section of the train would lose its vacuum supply (and therefore its braking) when the train separated.

To combat the problem, engineers started using the vacuum to hold brakes off as opposed to pulling them on. This method became known as automatic vacuum braking and was advantageous because if a pipe was to separate mid-journey, the vacuum would be lost and the spring-loaded brakes would automatically apply, thus stopping the train.

The system worked and was failsafe, however, it was also expensive and railway companies were reluctant to install it voluntarily. It wasn't until a horrific rail crash at Armagh in 1889 that automatic vacuum brakes became mandatory and remained the standard until air brakes replaced them in the 1970s.

Posted in: Rolling stock

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