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Signalling for modellers who don't know much about signalling


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Hundreds of examples where the home (on one line) is after the platform - don't confuse a station with station limits.

 

Fair enough, but equally... 

 

I'm trying not to! As was said earlier, stopping at the platform has more to do with the timetable than the signalling...

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It's not extravagant if the complexity of the moves justifies it. In my example you want to minimise the risk because it's mixing passenger trains, military dangerous goods and heavy loaded wagons of clay products. You have to consider there were regional differences, historic rights and different levels of traffic.

If a line has two or three trains a day and low line speed then you could get away with blocking up the whole station for an hour or so shunting but if that's on a busy through line with restricted sighting it's going to be a lot faster with full Signalling as it takes time to keep walking back and forth to change points and hand signal.

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It's not extravagant if the complexity of the moves justifies it. In my example you want to minimise the risk because it's mixing passenger trains, military dangerous goods and heavy loaded wagons of clay products. You have to consider there were regional differences, historic rights and different levels of traffic.

If a line has two or three trains a day and low line speed then you could get away with blocking up the whole station for an hour or so shunting but if that's on a busy through line with restricted sighting it's going to be a lot faster with full Signalling as it takes time to keep walking back and forth to change points and hand signal.

 

Exactly so. So signalling a layout depends on more than just the track plan.

 

Which is easier - working ground signals or a working signalman showing a green flag out of the box window?

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If it's blowing a hooly or driving rain or snow definitely a signal purely on visibility grounds ;)

The Signalman is working either way, if he pulls off a signal he can get on with other moves, he has to stand there holding a flag and can't do anything else.

Edited by PaulRhB
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The clearing of a signal also proves the points are fitting up properly.

 

 

Yes, this is assured by the interlocking,  The signal physically cannot be cleared, the lever cannot be pulled as a locking bar prevents it, unless the road is correctly set.

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Yes, the point lever can be pulled, and then the locking will permit the signal lever to be pulled, but that does not prove the point switches are correctly closed, or in an extreme case have actually moved. It is the "Detector", either mechanical or electric, worked by the Point Stretcher that allows the signal to clear..See attached simplified drawing. attachment=893635:DETECTION 1.jpg]

post-702-0-94025700-1504307209_thumb.jpg

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Sorry chaps, but no. Once again, it depends upon the railway in question, but if you look at the GWR or (to a lesser extent) the SR, then the terms 'Home' and 'Starter' - and the variations thereof - relate to the position of the signal relative to the controlling signal-box. So, in the example diagram 2 is a Home, even though in effect it controls 'starting' from the station. Most models do have 'station limits' which exist within the modelled area, with the start/end of the 'block sections' often - but not always - being within the visible modelled area.

The vast majority , of model railways do not operate a block system , even if they try to simulate one. Hence there is no box in advance or in the rear . Hence my comment that there are in effect no block sections or station limits. Hence my comment that all signals in such cases are in effect simple " stop " signals

 

Remember this is a signalling a model thread not a discussion of the real thing

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The vast majority , of model railways do not operate a block system , even if they try to simulate one. Hence there is no box in advance or in the rear . Hence my comment that there are in effect no block sections or station limits. Hence my comment that all signals in such cases are in effect simple " stop " signals

 

Remember this is a signalling a model thread not a discussion of the real thing

So the terminology of parts of a loco should change because it's not the real thing? :no:

Any model railway is a model of part of a railway system, the signalbox doesn't become a shed because they didn't model another box so a Home signal is still a Home signal by it's placing in relation to the station limits.  Distants aren't stop signals so we don't change their name so why not call the one in the appropriate place a Home or Section Signal? Modelling is about learning too so why not learn what they are as the reason is important IF you choose to include them on your model.

This is about helping people to make their model a bit closer to the real thing, if they so choose, so the correct name helps describe which signal you are talking about it just confuses the issue if we add another level of description for something that already has a perfectly usable name.

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The vast majority , of model railways do not operate a block system , even if they try to simulate one. Hence there is no box in advance or in the rear . Hence my comment that there are in effect no block sections or station limits. Hence my comment that all signals in such cases are in effect simple " stop " signals

Remember this is a signalling a model thread not a discussion of the real thing

However this is precisely where modellers go astray.

 

You can say 'it's only a model' as much as you like - but unless you are modelling an entire railway system with no external influences then you CANNOT ignore what happens off stage if you want to start signalling a layout with any degree of accuracy. If modellers do adopt such an attitude then they should stop asking for advise because it's a pointless executive - they might as well stick signals where they want and be done with it.

 

As I have said before when this topic comes up, the first thing a modelled needs to do is draw out the wider railway environment in which their small modelled section sits. Are we talking about a sleepy branch line worked by tokens, a busy terminus / urban railway with Absolute block signalling, a modern railway with track circuit block and multiple aspect signalling? All require a different mindset and approach when it comes to placing signals and as such skimping on such details is a recipe for chaos.

 

Once the wider railway enviroment has been defined however, signalling the layout actually becomes a bit more straightforward as you can then use the real thing for inspiration.

 

Yes signalling seems complicated as a subject when taken as a whole, but if you break it down and only focus on what you need to know it is not that hard to understand. For example if you are modelling a area signalled by absolute block then that is what you need to research - NOT modern multiple aspect signalling.

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However this is precisely where modellers go astray.

You can say 'it's only a model' as much as you like - but unless you are modelling an entire railway system with no external influences then you CANNOT ignore what happens off stage if you want to start signalling a layout with any degree of accuracy. If modellers do adopt such an attitude then they should stop asking for advise because it's a pointless executive - they might as well stick signals where they want and be done with it.

As I have said before when this topic comes up, the first thing a modelled needs to do is draw out the wider railway environment in which their small modelled section sits. Are we talking about a sleepy branch line worked by tokens, a busy terminus / urban railway with Absolute block signalling, a modern railway with track circuit block and multiple aspect signalling? All require a different mindset and approach when it comes to placing signals and as such skimping on such details is a recipe for chaos.

Once the wider railway enviroment has been defined however, signalling the layout actually becomes a bit more straightforward as you can then use the real thing for inspiration.

 

As a signalling aficionado and with a reasonable , even detailed knowledge of my own prototype and timescale , I am uncomfortable finding myself on the other side of this argument.

 

However, based on feedback from my club and looking at members own layouts . I would point out the following

 

Many layouts are fictitious in the extreme, with modellers often running a mix of regional stock , stock of different eras etc.

So decisions on the type of signal are often down purely to the whim of the modeller.

Even so , in LQ, UQ and colour lights , we have the concept of a simple " stop " signal

I have specifically excluded , in this context the concept of Home and Starters etc. This is because this concept is meaningless in the context of these layouts. Homes are merely stop signals in this context , they carry no other purpose

 

What many modellers ask for is a simple approach to " signal their layout " in some form that isn't meaningless

 

The suggestion that you must be aware of what's happens offscene is frankly ridiculous in this context , there is no offscene., typically the train loops around on itself

 

In this case, I suggest that modellers are simply siting " stop " signals. There are typically no distants

 

" note that the nomenclature of " stop" signals is correct, this is generically what they are.

 

I can see the aficionados aren't for turning on this one

 

So back to my 61 lever project , with computer generated ETS belling and tokens project , onwards towards my working ground signals !!

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The suggestion that you must be aware of what's happens offscene is frankly ridiculous in this context , ...................................

 

Why? My line is a joint station which splits between ex-LNW and ex-GW at the next signal box a few hundred yards away. It needs a lower distant arm under the starter to make sense. What i have to decide now is if it should be a single fixed distant, a single working distant for one line or a splitting distant for both lines at the off-scene junction.  

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Having read some of the posts in this topic it seems to me that there are too potentially irreconcilable positions being taken.

 

On the one hand we have the professionals - they know the full complexities of railway signalling and can explain all the background with reference to the block system, interlocking etc etc

 

On the other there is a modeller who wants to make his signalling look convincing, including the aspects it shows BUT...

 

Doesn't have a block system 

May well have only one signal box

Has no interlocking

 

Now it seems to me that that modeller can quite legitimately ask where do I put what signals on my Caledonian BLT or my LNWR double track junction or whatever. His model will be riddled with compromises dictated by space, time, ability etc etc. Which means that a full implementation of all the safety devices that a real railway would have is not going to happen. How many model railways have full interlocking? Some do, most don't. How many have separate signal boxes communicating with bell codes? 

 

So, for most modellers (I would assert) what would be helpful would be a basic guide of the the type that the OP obviously has in mind. The modeller who wants to acquire the sort of in-depth knowledge that the professionals have can get it but for others it may not be what they want to concentrate on.

 

I have built a number of etched brass locomotive kits. They look reasonably convincing from the outside but they are only superficially accurate. Inside the firebox or the boiler lurks an electric motor. The springs under the axles are rigid white-metal castings and there is no water, fire or steam involved.

 

The signal they run past is operated by a point motor controlled by a switch. This signal is normally "pulled off" by the bloke driving the loco. WOOPS! 

 

post-9071-0-02931800-1504341863_thumb.jpg

 

My point is that we should respect the knowledge that the professionals can bring to bear - when someone knows enough to say "The LSWR never used that" or "That signal should be before the siding points" fair enough. But the professionals should be prepared to concede that a model, already heavily compromised for all sorts of reasons, will have to compromise with its signalling too. 

 

I'll shut up now.

 

Chaz

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As a signalling aficionado and with a reasonable , even detailed knowledge of my own prototype and timescale , I am uncomfortable finding myself on the other side of this argument.

 

However, based on feedback from my club and looking at members own layouts . I would point out the following

 

Many layouts are fictitious in the extreme, with modellers often running a mix of regional stock , stock of different eras etc.

So decisions on the type of signal are often down purely to the whim of the modeller.

Even so , in LQ, UQ and colour lights , we have the concept of a simple " stop " signal

I have specifically excluded , in this context the concept of Home and Starters etc. This is because this concept is meaningless in the context of these layouts. Homes are merely stop signals in this context , they carry no other purpose

 

What many modellers ask for is a simple approach to " signal their layout " in some form that isn't meaningless

 

The suggestion that you must be aware of what's happens offscene is frankly ridiculous in this context , there is no offscene., typically the train loops around on itself

 

In this case, I suggest that modellers are simply siting " stop " signals. There are typically no distants

 

" note that the nomenclature of " stop" signals is correct, this is generically what they are.

 

I can see the aficionados aren't for turning on this one

 

So back to my 61 lever project , with computer generated ETS belling and tokens project , onwards towards my working ground signals !!

 

But thats the point - as far as modellers are concerned trains don't simply 'loop round on themselves' - they are imagined as going from Great Gooseberry to Chipping Driveway (or whatever the places may be called). A train that goes round and round the same place is just a kids train set and no different conceptually to a fairground ride.

 

We all have something called imagination - how hard is it to employ that trait and imagine your model in a wider setting?

 

In fact pretty much every single club layout I have seen (and most of those featured by forum members in their posts) show just that principle, as the layouts are built around modelling a specific era or situation. Nobody can model an entire railway system so we take a small slice and recreate that in model form. Sure at times people will run what they want on it, but thats very different to just randomly throwing stuff together in some vague manor without a  coherent idea as to what they want to achieve from it

 

Thus if the idea is to create an impression of a between the wars branch line, then the signalling will need to confirm to a certain basic set of principles (even if compromises are necessary due to the use of 'ready to plonk' signals) to ensure that the overall 'impression' matches the theme set by the creator. If on the other hand you are attempting to create a late 50s transition era secondary line in an urban area with colour light signalling then completely different principles come into play. Again compromises may be needed due to the availability of signal types but it is a fundamentally different situation and the signalling needs to reflect that.

 

That is why there is a need for publications such as those being discussed in this thread - something to guide the modeller into adopting, as far as the modellers skills / availability of products allows) the correct signalling for their chosen era.

 

However, you will be happy that I do agree with you on one thing - given the space restrictions most modellers face there really isn't any point worrying about distant signals as if they are sited correctly they will never unusually be present on the scenic bits of the layout anyway*

 

*Those who are not clued up on signalling please take note:-  a semaphore distant signal being 'on' or 'off' means something completely different to a driver to a yellow or green colour light aspect!

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Now it seems to me that that modeller can quite legitimately ask where do I put what signals on my Caledonian BLT or my LNWR double track junction or whatever. His model will be riddled with compromises dictated by space, time, ability etc etc. Which means that a full implementation of all the safety devices that a real railway would have is not going to happen. How many model railways have full interlocking? Some do, most don't. How many have separate signal boxes communicating with bell codes? 

 

 

 

You are going to deep - while he physical equipment will of course vary, a LSWR double track line in Devon signalled by Absolute block will share exactly the same fundamental principles as a Caledonian one in Perthshire. They will both have a signal that functions at the exit from the block section and another that controls entry to the next one. They will also probably both have distant signals - though given the size of most models these would not need to be considered. They both would have something called 'station limits' (which may or may not have a station) controlled by a single signal box.

 

THESE are the sorts things modellers need to be aware of to understand how to signal their layout with semaphore signals - whether the signals go up or down or 'off' is really rather irrelevant to the important mater of where they should be placed

 

As I have already pointed out one of the classic mistakes is for modellers to think a semaphore distant signal means the same as a yellow or green on a colour light signal - and that a stop signal with a distant below it is the mechanical version of a 3 aspect colour light signal!

 

THAT is the sort of thing many of us 'professionals' are trying to prevent by directing modellers to understand the basic principles of signalling.

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Ah, now your layout has a signal for every move. As I understand it, in many places such extravagance was avoided and all shunting was done by hand signals within station limits - no ground signals. Hence my remark about that up home signal. I have in mind the classic Midland wayside station layout, of which Monsal Dale is a nice simple example.

 

The BoT, from quite an early date, required that ground signals be installed controlling the exits from sidings on to running lines. In many cases, right through the steam era, these were the only ground signals to be found at smaller stations (and occasionally they were actually point indicators which worked automatically with the adjacent points). The only exception to this rule was when the siding connection was controlled from an immediately adjacent ground frame. As has been stated, in the absence of fixed signals, hand signals were used.

Edited by bécasse
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My point is, even if the signals are off-stage, one should operate believing in their existence.

My ultimate long-term goal (if I ever get that far, and get a good enough grasp of the subject) is to operate with an interlocked lever frame that includes all the signals off the layout (and would points too, but hopefully they'll all be on it), so I'll still have to move levers that move imaginary signals, or ones that can't move in reality, since I've not yet decided whether I'm going to try to make the ground signals move.

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The BoT, from quite an early date, required that ground signals be installed controlling the exits from sidings on to running lines. In many cases, right through the steam era, these were the only ground signals to be found at smaller stations (and occasionally they were actually point indicators which worked automatically with the adjacent points). The only exception to this rule was when the siding connection was controlled from an immediately adjacent ground frame. As has been stated, in the absence of fixed signals, hand signals were used.

 

From what date? Monsal Dale, 1966, has none but the exit from the down siding to the up and the nearer exit to the down are right in front of the signalbox and the further exit is controlled by the ground frame, which you've explained. Leafing through the 1950s - 60s signalling diagrams in Anderson & Fox's Settle & Carlisle book, I see that there are ground signals controlling all exits onto the running lines, as you say, but not (usually) for setting back into sidings except in some cases (but not all) where the points are far from the signalbox - the choice might have to do with visibility?

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The signal they run past is operated by a point motor controlled by a switch. This signal is normally "pulled off" by the bloke driving the loco. WOOPS! 

 

attachicon.gif P1060245-2.jpg

 

Chaz

What you say is true enough, but remember it is a 'model railway', do some take it a bit too far ( sometimes, like a few other threads, I worry why????), I for one wasn't worried about the position of the signal arm - but LIKE the N7. :sungum:

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From what date? Monsal Dale, 1966, has none but the exit from the down siding to the up and the nearer exit to the down are right in front of the signalbox and the further exit is controlled by the ground frame, which you've explained. Leafing through the 1950s - 60s signalling diagrams in Anderson & Fox's Settle & Carlisle book, I see that there are ground signals controlling all exits onto the running lines, as you say, but not (usually) for setting back into sidings except in some cases (but not all) where the points are far from the signalbox - the choice might have to do with visibility?

Looking at signal-box diagrams "in isolation" is also fraught with problems. Many layouts were altered over the years, at different times with different standards/requirements in place, so it was quite common to find somewhere with shunt signals at some points and none at others. To 'understand' the signalling of a prototype you need to know more about its history. This is why two or three seemingly identical layouts on the same railway may appear to have been signalled in different ways.

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This thread is very interesting but does not achieve the purpose of a simple guide to putting signals on a model railway. Perhaps the subject is too complex for that unless one is prepared to accept an over simiplified signalling arrangement. After all, so what if it is not quite accurate. Unlike the prototype no one's life depends on it.

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