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Discussion Starter · #1 ·
As my lay out is now progressing at a steady rate, I want to start putting on the signals.

This is something I have never had on a layout before as my last one I was only a young lad and not into all the 'Bits' to make it real.

I do not have a huge understanding of signals, so where is the best place for knowledge on this?

ie, What signals where, Home and Distant?????

Relation of points to signal and vice verse

Cheers
Cpt Jact
 

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Welcome to this specialist bit of the Forum.

Deciding where to put signals on a model railway is difficult, mainly because the distances are so compressed that Distant signals, for example, would often be well off the scene.

I would recommend visiting John Hinson's web-site on signalling matters www.signalbox.org which gives a straightforward description of the British signalling system.
For books I'd suggest "Railway Signalling and Track Plans" by Bob Essery, published by Ian Allan in 2007, ISBN 978 07110 32156. This describes how the prototype did it with some comments at the end about interpreting it into model form.

If you want to post track plans here a couple of us will try and suggest where you might put signals (on the layout, that is!).

Regards,
John Webb
 

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Discussion Starter · #5 ·
QUOTE (Lancashire Fusilier @ 21 Oct 2008, 03:34) <{POST_SNAPBACK}>Capt, please post up your track plans cause if it's signalling you're after it's signalling you're gunna get mate!

That's very kind of you


Cheers
Cpt Jack
 

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Can we conclude that signals are to give train drivers instructions about the state of the line ahead?

So if there is a junction, point, crossing, siding, station or stopped train up ahead then a signal will be in place to protect the line where the problem could occur.

A stop signal (home?) is where the train must stop, and a distant signal is located at the point where the train must start breaking so that it can stop in time at the stop signal if the stop signal is in the 'stop' position.

Is this right?

I want signals to tell me the state of the layout so I can walk around and drive the trains. I don't want to have to look back at the control panel to see if the points ahead of me are set for or against me.

I really hope that Hornby, Bachmann or another large company can produce a range of semaphore signals that are ready and easy to use as well as being reasonably priced.
 

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Paul Hamilton aka &quot;Lancashire Fusilier&quot;
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Doug, everything you say makes sense.

Capt. What era is your layout set in? I am assuming some sort of semaphore signalling would be what you want, as accurate as is practical with considerations that distant signalling on most modest layouts is not really practical due to the length of the block section and as a compromise having a fixed distant on a home signal is sensible.

If it is coloured light then it is a different approach.

I would suggest too that your layout could benefit from another signal box, perhaps near the goods shed on the lower level.

If you haven't already have a look at my thread on my layout here signalling as there are some similarities present.
 

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Discussion Starter · #8 ·
QUOTE (Lancashire Fusilier @ 21 Oct 2008, 12:17) <{POST_SNAPBACK}>Doug, everything you say makes sense.

Capt. What era is your layout set in? I am assuming some sort of semaphore signalling would be what you want, as accurate as is practical with considerations that distant signalling on most modest layouts is not really practical due to the length of the block section and as a compromise having a fixed distant on a home signal is sensible.

If it is coloured light then it is a different approach.

I would suggest too that your layout could benefit from another signal box, perhaps near the goods shed on the lower level.

If you haven't already have a look at my thread on my layout here signalling as there are some similarities present.

Hi there, set in the early sixties, and yes semiphor is th style I want, I have since built a second signal box and it's ready to go in location.

Cpt Jack
 

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Hi Cap'n.

Just found your thread which I must have missed first time around.

I too have been looking at signalling for my layout, which, incidentally, bears a striking resemblance to your own. However, the more research I do, the more confused I get.

I think I have cracked the 'Home' v 'Distant' issue but the difference between Upper and Lower Quadrants is totally eluding me. Common sense would suggest that upper quadrant signals should be taller than lower quadrant but, having looked at countless pictures, I find that this is most definitely not the case as I've found pictures of lower quadrant signals which are taller than upper quadrant and vice versa.

As I am modelling GWR I am aware that GWR used lower quadrant only and I would therefore not wish to have an upper quadrant signal by mistake.

If anyone else reading this thread can enlighten me I would be very grateful. Incidentally a diagram of my layout can be found in my 'Model of the Model' photo album if that is any help.
 

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The GWR (and subsequently the WR of BR) always used lower quadrant signals, as indeed did other companies, for example the Midland Railway. But as I understand it, the lower quadrant arms needed heavy cast 'spectacles' (the bit with the coloured glass in) to ensure that that end of the arm was the heaviest so that signals automatically returned to the horizontal 'danger' position if any connection between the arm and the bits at the bottom of the signal post broke.

As signals developed, the upper quadrant became favoured as the arm and the spectacles could be made from lighter and thinner metalwork, yet the arm would still return to horizontal if the connections broke. But with the lighter and cheaper metalwork the signals were less costly to make and easier to maintain.

All signals, upper or lower quadrant, were sited at a height where the driver and fireman had the best view on approaching them. The various railway companies also had different driving positions for various historic reasons, and the GWR locos were all driven from the right-hand side. So the signals on the GWR had to be placed where the driver on the RHS of the loco could see them.
But railways are crossed by bridges and at stations there are buildings and canopies which may obstruct the view of signals. So the signals may have to be placed at different heights to give the best view. Even today with colour-light signals they still have to have 'Sighting Committees' when resignalling is taking place to ensure that the signals are placed where the drivers of all sorts of trains have the best view.

Take a look at www.signalbox.org which has a comprehensive history of British signalling and many examples of signals and signal boxes from pre-grouping to BR.

Hope the above helps,

Regards,
John Webb
 

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Hi John,

Thanks for the potted history but it still doesn't answer the question. What exactly is the difference between Upper and Lower Quadrant signals? Is it just the way they were made ?
 

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QUOTE What exactly is the difference between Upper and Lower Quadrant signals? Is it just the way they were made ?

Consider a signal at danger. The arm is in the horizontal position.

  • When a lower quadrant signal is cleared, it drops to the lower quadrant of an imaginary circle with its centre at the pivot point of the arm.
  • When an upper quadrant signal is cleared, it is raised to the upper quadrant of the same imaginary circle.
As John has already stated, a signal should fail to the danger position.
  • A lower quadrant signal, there must be a heavier counter balance to pull the arm back horizontal position.
  • An upper quadrant signal can fall back under its own weight
There is another significant difference in appearance between the two signal types.
  • The spectacle plate (the Red and Blue/Green) filters of a lower quadrant signal are arranged vertically. This gives the signal an overall "J" shape.
  • The spectacle plate filters of an upper quadrant signal are arranged horizontally. This means the signal arm is little more than a bar.

I hope this helps

David
 

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Trevor - sorry I didn't make clear the difference. The website I gave you above has much better diagrams and pictures than I could give you, so take a look at that for the detailed information.

And if you wondered why David (dwb) refers to 'Blue/Green' for one of the filters it's because the yellow light from the oil lamp behind the spectacles passing through a blue filter gives you a green light with minimum loss of intensity.

Regards,
John Webb
 

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Paul Hamilton aka &quot;Lancashire Fusilier&quot;
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QUOTE (Cpt Jack Sparrow @ 3 Feb 2009, 16:10) <{POST_SNAPBACK}>I did, 4 posts above this one.

Sorry about then. My new work has something that prevents these images from being displayed and I can't see anything. Oh well, John is on the case and he is excellent and did several iterations of mine.
 

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QUOTE (dwb @ 4 Feb 2009, 00:47) <{POST_SNAPBACK}>I hope this helps

David

Thank you very much David for your very clear and concise response. I have not seen this difference clarified in any of the books or magazines I have read but now I understand it fully. It's so simple really.

Thanks again
 

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Right, I've had a quick look at the plan and need to ask a few questions about parts of the Layout.

'Main Line Terminus'
Whats the purpose of the short line stopping short of the end of the lower platform?

'Branch Line Terminus'
Headshunt to Goods Shed - is this a platform face that could be used by a passenger train, or is there a wall or fence shutting off the line from the platform?
Likewise the line acting as a headshunt into the engine shed - is that also isolated from the platform?
(Just that if passenger trains are to use those tracks, the signalling requirements are more strict than if they are goods only.)

Regards,
John
 
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