Signalling for modellers who don't know much about signalling

[The Stationmaster]

And that remark gets us how much nearer to a solution?  Yes, I meant block section.  Now answer the question.

 

Look at the list in Post 198 - that tells you what stop signals are needed for so you can start to grasp from that (I hope) where some of them will go.  That of course does not take account of how different Companies/Regions did it in their particular way nor does it give you precise positions but that is about as simple a list as can be produced of the way stop signals are used.

[The Stationmaster]

The picture you reference , as I understand it , is two starters and the accompanying text explains there used to be a siding between the two.

 

But these are " edge " cases and largely irrelevant for vast majority of model railway layouts . We can all document unusual situations on the prototype , but this doesn't deflect the basic argument

 

 

With reference to post 198, this isn't sufficent to allow modellers to position signals. The key way to do that is a series of diagrams showing the position of junction signals , typical home signal positioning , including outer homes , starters and advanced starters etc. Ground signals can be ignored as few layouts have working examples

 

Yes it can get complex but that's not the point , nor is pointing out oddities with the prototype , because modellers arnt generally going to model oddities unless they are following a prototype , and in that case they can reference the prototype directly

 

If you want diagrams you need a book.  Sorry but that list strikes me as pretty clear (I would say that wouldn't I) but if anyone wants to go further and can't visualise a stop signal protecting a trailing point without a diagram you need a heck of a lot more than diagrams because you get into all sorts of other areas which take us into slightly different realms but they might not make much sense unless you know the basic reasons for having a stop signal.

 

Thus below -

1. A stop signal protecting a level crossing  (but also protecting the facing connection in advance of the crossing).  The signal in the opposite direction serves exactly the same function but its position depends on the trailing point and the crossover it makes which is out of shot.   It is also the Section Signal. Key feature A - a stop signal protecting a level crossing can be very close to that crossing.  Key feature B - a stop signal can perform more than one function depending on track layout etc.

 

 

 

2. A clearer view of the signal in the opposite direction showing how it is placed well in rear of the fouling point of the crossover which it protects in addition to protecting the level crossing

Key feature - position of a stop signal protecting a trailing connection.

 

 

3. A stop signal protecting a trailing point, it is also the Home Signal.

 

 

4. Another stop signal protecting a trailing point.  Although it is at the end of a station platform its primary role is to protect the trailing point.

 

 

5. The back of a splitting stop signal protecting a facing point.  Key feature - see how close it is to the point toe - a typical arrangement in semaphore signalling partly resulting from the Requirement to ensure that the points cannot be moved under a train which is passing over them

 

 

6.  A stop signal protecting a trailing point. 

 

 

7. But look how different things can be.  Key feature - past rationalisations can lead to signal positions being different from what one might expect plus signal sighting (by Drivers) is as important as signal siting (i.e where the signal is) - thus signal 2 is 236 yards from the level crossing it protects (for sighting reasons on a curve plus a former station has gone) and is also the Home Signal whilst again for sighting reasons the Section Signal, No.3, is on the wrong side of the line.  But look too at the opposite direction where Signal 14 is 88 yards from the level crossing but also protects the trailing crossover - apart from which it is both the Home Signal and the Section Signal.

Key feature - signal sighting is as important as signal function and can affect the position of signals.  Key feature - once again a single stop signal can perform more than one role, in this case Signal 14 is performing 4 roles and its siting reflects 2 of them.

 

 

8.  But beware of traps - these 3 stop signals on a  bracket structure apply to three different lines and protect the departures from bay platforms towards trailing points (and thence in one case through a facing point).  The arrows - a poost mid 1990s addition give a clue they apply to different lines.  Key feature - things might not be what they seem when looking at photos or diagrams unless they are further explained.

 

 

Seen from the back of the signals things are a bit more obvious, and we can also clearly see a splitting stop signal protecting a facing point  -

 

[big jim]

whats that old saying "a picture paints a thousand words"

 

where is/was the triple arm signal mike, at a first glance without your explination (or arrows) i'd read it as there is a 3 way junction ahead and the signal applies to the line to the right of the platform but with your explanation im now looking at it as 65 is the left hand line (line with tpws grid), 52 is the right hand platform and 54 is the furthest right bay road which to futher complicate things has a signal near the end (the one that is off) that relates to the line your train is departing from!

 

i assume its a through station by provision of the distant on SM47 signal?

 

and people wonder why i wont sign them off on the route through shrewsbury without a walk round and a visit to the boxes, thats as complicated as your pics in places!

[Martin Shaw]

Jim

 

It's Stirling Middle, I haven't been there for a while so the current position is probably a bit different., there has been some rationalisation. The distant under SM47 is for Stirling North. The three way bracket is as you surmise correctly, The off arm at one time had a distant arm for Stirling South, long gone, although I agree if you don't know the layout the capacity to confuse is great

 

Regards

Martin

[Junctionmad]

 

 

'd read it as there is a 3 way junction ahead and the signal applies to the line to the right of the platform

without a diagram and just seeing it , thats exactly  as how I would see it too. I was always of the view that semaphores brackets were predominantly " route indicators " and not " protecting crossing ahead " as a primary function ( since that could be done with a single arm ) 

Edited September 10, 2017 by Junctionmad

[Junctionmad]

Heres the diagram , personally Id say the bracket  platform starter is unusual to say the least  SM 10 , 30,34 being more usual in indicating routes , but  I can see the point of 65,52,54. because all those lines lead more or less directly onto the UP line.  They are in effect simply a space saving way of not having three separate  signal posts, but in reality they are read exactly as if there were three separate posts ( i.e. unlike bracket signals that typically read from one line to multiple routes  ) 

 

Again, getting back to the OP, where this example is " interesting ", its not at all terribly relevant to the average modeller, typically siting platform starters ?

 

Edited September 10, 2017 by Junctionmad

[runs as required]

Merely clicking Informative/useful seems an inadequate response to Stationmaster's well thought out selection of signal pics with  attendant commentary.

 

It seems evident from the range of posts on this thread that there are a good many railway enthusiasts who could be entranced for hours by a pictures-with-extended captions printed book or web site on signalling.

 

So how might it be structured? One might immediately think chronologically. But modellers would probably wish to skip flag waving, discs and slotted posts, opting instead for modelling epoch

i.e. post Grouping Big 4; BR early/late or by Region.

Others might want a typology of single/double line and junction formats and through or terminus station layouts rural and urban.

Traditionalists might just want semaphores, some opting for colour light as easier to animate.

Then there would be the Modern Image/contemporary scene.

 

Mmm...difficult subject

dh

 

Ed of typos

Edited September 10, 2017 by runs as required

[Junctionmad]

again , I think a book about signalling for railway modellers, would be heavy on using fictitious layouts to illustrate " typical " placement and usage of signals.  helped by some useful prototype pictures to illustrate the diagrams.

 

whats not useful to beginners is pictures of prototypes illustrating signalling in itself , because typically  such modellers cant relate the prototype correctly to their model.  ( if they could , they wouldn't be on here , with cries of " signal my layout for me please " ) 

 

Hence the nice idea to signal CJF's Minories and perhaps some others from the same book etc 

Edited September 10, 2017 by Junctionmad

[Clive Mortimore]

again , I think a book about signalling for railway modellers, would be heavy on using fictitious layouts to illustrate " typical " placement and usage of signals.  helped by some useful prototype pictures to illustrate the diagrams.

 

whats not useful to beginners is pictures of prototypes illustrating signalling in itself , because typically  such modellers cant relate the prototype correctly to their model.  ( if they could , they wouldn't be on here , with cries of " signal my layout for me please " ) 

 

Hence the nice idea to signal CJF's Minories and perhaps some others from the same book etc 

Hi

 

I have signaled a Minories type layout. Mike was very kind and only suggested that an outer home was added, which would be off scene.

 

[The Stationmaster]

without a diagram and just seeing it , thats exactly  as how I would see it too. I was always of the view that semaphores brackets were predominantly " route indicators " and not " protecting crossing ahead " as a primary function ( since that could be done with a single arm ) 

 

When I first saw it (some years earlier and without the arrow signs) I had exactly the same thought, until I looked at the track layout because the spacing of the dolls (the small posts which carry the arms) was typical of a splitting signal rather than the way I would expect them to be arranged for three separate lines.  Clearly the Caledonian Railway didn't waste money on such fancy ideas as making the purpose of some of its signals as clear as we might like.

 

And several people have lighted on my reason for including the picture as even in photos there is a need to try to understand what might be happening and one which doesn't show the track layout can mislead. 

[The Stationmaster]

Merely clicking Informative/useful seems an inadequate response to Stationmaster's well thought out selection of signal pics with  attendant commentary.

 

It seems evident from the range of posts on this thread that there are a good many railway enthusiasts who could be entranced for hours by a pictures-with-extended captions printed book or web site on signalling.

 

So how might it be structured? One might immediately think chronologically. But modellers would probably wish to skip flag waving, discs and slotted posts, opting instead for modelling epoch

i.e. post Grouping Big 4; BR early/late or by Region.

Others might want a typology of single/double line and junction formats and through or terminus station layouts rural and urban.

Traditionalists might just want semaphores, some opting for colour light as easier to animate.

Then there would be the Modern Image/contemporary scene.

 

Mmm...difficult subject

dh

 

Ed of typos

Just to give an example of one way of doing it my manuscript (all 100,000 incomplete words of it plus several hundred photos taken purposely to illustrate it - and none of them have appeared in this thread as it happens) was arranged thus with the idea being that knowledge would be added in logical steps based on what had already been read.  Whether it would or wouldn't have been split into two volumes depended very much on the publisher and keeping the cost at a realistic level as it would be 'photo heavy' with numerous diagrams as well as the text with Chapters 7 onwards being n the wrong place for, probably most modellers' needs.

 

 

[Talltim]

There's some good signals here!

[big jim]

Ok I'm gonna have to ask, is that a photograph or a computer generated image, I'm finding it hard to tell

[runs as required]

Oh my! Oh my!

Lower quadrant stuff; was that the throat of L,C,D & E C R  Chesterfield Market Place?

dh

[Pacific231G]

Oh there's lots of things changing, imagine my confusion when told :

 

"The fault was caused by the light engine on the signal. . . What it's run over it?

No it failed. . . So how's it on the signal then? What are you calling a light engine?

The lamp on the signal! . . . Well why didn't you call it a lamp then!????"

 

Why do we need to invent new names for something that has a perfectly adequate name? Call it the lamp unit don't call it the same as another common railway term!

I've got used to the new terms for either side of the signal ,although I was totally happy with the old ones, the new ones are always referencing the front of the signal is how I remember it.

Under and Overbridges also befuddle a lot of people.

 

A cynical, but probably often too true view, is that experts invent new names for things to ensure that their expertise isn't shared by too many people thus reducing its apparent worth. It is perhaps a bit like the wartime farmer told by the ministry bod that he should be referring to fertiliser and not manure. The farmer's wife immediately commented that it had taken her twenty years to get him to call it manure.

 

BTW, is a common crossing a working class frog?

 

 

I really hope 'spoiling your kipper' isn't a euphemism...

Whatever failings BR might have had, the quality of their restaurant car breakfasts was certainly not one of them. Edited September 11, 2017 by Pacific231G

[RailWest]

Oh my! Oh my!

Lower quadrant stuff; was that the throat of L,C,D & E C R  Chesterfield Market Place?

dh

If you look at the bottom left, it says 'Boston, Mass'. More obviously, all the signals are the wrong way round for the UK, as they point to the right not the left !

[Compound2632]

If you look at the bottom left, it says 'Boston, Mass'. More obviously, all the signals are the wrong way round for the UK, as they point to the right not the left !

 

I though there was something odd about it. Apart from being the wrong way round, it looks surprisingly British. Until I saw the small print, I was thinking Australia.

 

They're evidently a very trusting lot, these New Englanders. No buffer stops!

Edited September 11, 2017 by Compound2632

[The Johnster]

Not the station throat at Hemyock, then?

[Colin_McLeod]

I believe I understand this thread now. As a lot of our layouts are roundy roundy it follows that the signalling thread would go round in circles. :

[St Enodoc]

There's some good signals here!

And those double slips are nice too.

[Compound2632]

I believe I understand this thread now. As a lot of our layouts are roundy roundy it follows that the signalling thread would go round in circles. :

 

That's right. And as we have our signals unprototypically close together, with all that slotting they'll either be all off or all on together - a great simplification.

[Dave John]

Hmm, so what we want is a simple roundy layout. Just an inner and outer loop. Stations close together, some as close as 800 yards.  Track gauge that scales out to four feet so OO is actually right. Easy to handle 3 coach trains. A simple signalling system that says stop or go and actually stops the trains if they go when they should not. 

 

 

Fantasy?  Nope, its called the Glasgow subway....... 

 

Sorry , couldn't resist. 

 

 

 

Actually one of my walks, I do a lot these days, is to walk the subway. I live a stones throw from kelvinbridge so thats number 1. You can follow it on google earth but I calculate that visiting every subway station on foot is about 25 miles of walking. Takes a full day but you do get to see a lot of the city. The Caledonian pup slept for ages after that one.

[Junctionmad]

 

 

A cynical, but probably often too true view, is that experts invent new names for things to ensure that their expertise isn't shared by too many people thus reducing its apparent worth. It is perhaps a bit like the wartime farmer told by the ministry bod that he should be referring to fertiliser and not manure. The farmer's wife immediately commented that it had taken her twenty years to get him to call it manure.

 

while this is often a view elucidated by those " outside " , its not why jargon gets invented. jargon is invented to name concepts or things that are specific to the industry in the name of brevity and understanding  amongst the cognoscenti.  Once a common understanding is reached within the industry on a term , it is then rapidly accepted, as its conveys a specific meaning to those that know. 

 

in that respect, the jargon or tech speak or a sector is not, by design, aimed at, the " general public ".  Where such communications are needed , geniuses! in the marketing department get together and produce " plain english " versions for the public.  Thats has it should be.  A railway signal engineer is not engaging with the public, he's or she is engaging with fellow professionals.  Try a lunch time chat with a group of software engineers, you'll be lucky to recognise it as english never mind jargon !!!!!

Edited September 12, 2017 by Junctionmad

[Chimer]

Indeedy.  Though on here the signal engineer is often engaging with the general public.  Anyway ...

 

I had a revelatory flash the other evening, realising that if a train is passing signalbox B, it makes perfect sense to describe box A, the last box passed, as "in rear", and box C, the next ahead, as "in advance" of the train, and therefore by useful extension is in rear/advance respectively of box B.  Because of course when you're going the other way, A is in advance of B, but you can now use the same terms to describe similar situations.  By further extension of this usage, then, the signal protecting a point is in rear of it.  But when the driver of the approaching train sees the signal and point together as he comes round the bend, and Mr Cuneo standing next to him paints the scene, the general public viewer in the art gallery (me) sees the signal in the foreground of the picture and the point to the rear of the scene.  To him, the signal is clearly in front of the point - and front is the opposite of rear.  When he hears the signal engineers in conversation next to him talking about the signal being in rear, he has, I think, a right to be confused - and the explanation of his confusion needs to be gentle.

 

Completely off topic, for Compound2632, I as a "former naval person" observe that "port" and "starboard" exist to resolve an ambiguity in the same way, but thankfully there is no non-marine situation in which port means right or starboard left.  We even pass the port to the left!  "Sheet" I give you - and I would expect most sailing instructors therefore avoid using it in the early days, and stick firmly to "rope".

 

Apologies for reverting once again to philosophy on what is turning out to be a fascinating thread which is answering many signalling questions, including lots I didn't know I needed to ask!

 

Cheers

 

Chris

Edited September 12, 2017 by Chimer

[Junctionmad]

Indeedy.  Though on here the signal engineer is often engaging with the general public.  Anyway ...

 

I had a revelatory flash the other evening, realising that if a train is passing signalbox B, it makes perfect sense to describe box A, the last box passed, as "in rear", and box C, the next ahead, as "in advance" of the train, and therefore by useful extension is in rear/advance respectively of box B.  Because of course when you're going the other way, A is in advance of B, but you can now use the same terms to describe similar situations.  By further extension of this usage, then, the signal protecting a point is in rear of it.  But when the driver of the approaching train sees the signal and point together as he comes round the bend, and Mr Cuneo standing next to him paints the scene, the general public viewer in the art gallery (me) sees the signal in the foreground of the picture and the point to the rear of the scene.  To him, the signal is clearly in front of the point - and front is the opposite of rear.  When he hears the signal engineers in conversation next to him talking about the signal being in rear, he has, I think, a right to be confused - and the explanation of his confusion needs to be gentle.

 

Completely off topic, for Compound2632, I as a "former naval person" observe that "port" and "starboard" exist to resolve an ambiguity in the same way, but thankfully there is no non-marine situation in which port means right or starboard left.  We even pass the port to the left!  "Sheet" I give you - and I would expect most sailing instructors therefore avoid using it in the early days, and stick firmly to "rope".

 

Apologies for reverting once again to philosophy on what is turning out to be a fascinating thread which is answering many signalling questions, including lots I didn't know I needed to ask!

 

Cheers

 

Chris

 

Your reference to Mr Cuneo, shows exactly was in the rear and in advance is used in signalling terms.  The terms apply to the direction of the train as it normally travels.  Hence the immediate confusion if you use  common terms , like " in front of ".   ( if you think about it , a signal in front of a point cant actually protect it !!, because what is the definition of the " front" of a point )

 

just like using left or right on a ship is ambiguous , because it refers to the orientation of the speaker , whereas the understanding of port and starboard is always in respect of the bow of the ship and hence to those that understand the point, its removes any ambiguity 

 

in exactly the same way to those that understand , the use of" in the rear " and "in advance " removes any ambiguity because in essence it references signalling to train direction , again because signalling is highly relevant to train direction 

 

I see no confusion , try putting a member of the public on a ship , theres no loo, no kitchen, only one rope, no front or back, left or right, no stairs, beds or floor!!!

Edited September 12, 2017 by Junctionmad