signals
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When wondering around exhibitions, it become
clear to me that many modellers make little attempt to get their signalling
correct. This is not at all surprising as it is an extremely complex
field. There are indeed some real experts around but they are quite thin
on the ground. I have one friend who actually operates his 009 narrow
gauge railway with beautiful replica lever frames and miniature electric
train staff.
working model of a miniature electric train staff by Bob Barnard
Airliners are the safest way to travel these
days. This can be partially attributed to the fact that the industry has
learned from its mistakes (crashes). In the same way, the safety
requirements of railways have become increasingly sophisticated in order
to avoid disasters of the past. Obviously, the worst thing
that can happen is a 'cornfield'. This is a head on collision between two
trains that have found themselves on the same track. Gradually, the design
of railways minimised the chances of this happening.
Just as in models, facing
points are a potential danger in real railways. Railway designers try to avoid this situation
when possible and require special locking devices in some circumstances.
In order to stop locos wandering onto the
main line from sidings, the siding may well be fitted with catch points.
These are interlocked with signals so only an idiot would actually drive
across one. Sadly we do have quite a few idiots around! The photo below
shows the consequences.
Peco catch point
Rather than tip over locomotives, where
possible a head shunt is installed. This also enables trains to shunt
without entering the main line.
So signalling is linked to point operation.
The levers in a signal cabin mechanically ensure that they are. Model
signals are available for some popular scales. Many are very crude and do
not operate. Probably the best signalling in several scales is produced by
Model Signal Engineering. Obviously, the
smaller the scale, the harder the kits are to build. This company will
also supply special motors that replicate the prototypical movement for
signals.
Some model signals can also be operated by memory
wire.
Of course the most wayward railways lines did not
bother with any of this and got away with it by operating one engine in
steam or ran at such a slow speed that nothing much would happen!
You will either get drawn in to this subject
or shy away. Working model signals, whether semaphore or lights does add
another dimension to your model railway. Many countries have signals which
are unique to themselves.
derelict French signals
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