Signalling for modellers who don't know much about signalling

[Chimer]

I'm not confused any more!!  You have explained perfectly clearly how the railway uses those terms, and why, and I now understand completely.  My point has always been that before I had that explanation my interpretation of the terms was exactly the opposite of what, in the railway context, I now know to be right.  Other people on here asking questions about signalling may not have the knowledge I now have, thanks to you and others, and may similarly misinterpret the answers if those terms are used without explanation.  Which I why I light-heartedly (!) asked people not to use them in answering my original question. 

 

In my opinion, when explaining anything to someone with less knowledge of the subject, jargon must either be explained or, preferably, avoided.  So you should either say "the signal comes before the point as the driver sees it" or "the signal is in rear of the point, which means it comes before the point as the driver sees it".  You shouldn't just say "the signal is in rear of the point".

 

For "runs as required" - Thank you.  Yes, I do feel better now, and was cross with myself the moment I pressed "post" last night.

 

Peace to the world!

[Colin_McLeod]

Peace to the world!

That reminds me. Christmas is coming and maybe Santa will bring me some Peco bullhead points.

 

 

Edited to correct the autocorrect!

Edited September 9, 2017 by Colin_McLeod

[The Stationmaster]

I would like to say, to get back to the OPs point , that in my view, it's entirely possible to produce a simple explanation of how to site semaphores on a model railway and how to avoid any obvious howlers in relation to the operation of those signals and the trains they control.

 

Yes such description will be by necessity generic and reasonably time period independent but the basics of semaphore signalling from the 1900s on, are very similar and reasonably consistent. Modellers looking for specific regional situations will of course need further research.

 

One only needs passing references to absolute block and various rules associated with it ( or single lines etc ) , most modellers will not be interested in block working , blocking back inside or outside the home, or shunting into forward sections etc. These concepts all presume you are in fact operating bells and blocks etc. They are meaningless and best ignored in the context of the average model railway layout.

 

These simplifications along with stacks of other compromises tend to known as " modellers license "

 

So what does the list in Post 198 do apart from exactly that? (although it does, inevitably, have to relate to block working and railway terminology in some respects in order to make complete sense or why else would there be stop signals a long way from any points).

 

And how else might you be able you make sense of something like this arrangement of stop signals at Ledbury (picture at top right of the linked page) -

 

http://www.roscalen.com/signals/Ledbury/

Edited September 9, 2017 by The Stationmaster

[The Stationmaster]

I'm not confused any more!!  You have explained perfectly clearly how the railway uses those terms, and why, and I now understand completely.  My point has always been that before I had that explanation my interpretation of the terms was exactly the opposite of what, in the railway context, I now know to be right.  Other people on here asking questions about signalling may not have the knowledge I now have, thanks to you and others, and may similarly misinterpret the answers if those terms are used without explanation.  Which I why I light-heartedly (!) asked people not to use them in answering my original question. 

 

In my opinion, when explaining anything to someone with less knowledge of the subject, jargon must either be explained or, preferably, avoided.  So you should either say "the signal comes before the point as the driver sees it" or "the signal is in rear of the point, which means it comes before the point as the driver sees it".  You shouldn't just say "the signal is in rear of the point".

 

For "runs as required" - Thank you.  Yes, I do feel better now, and was cross with myself the moment I pressed "post" last night.

 

Peace to the world!

 

This is one reason where I feel the forum/thread approach falls down.  I can absolutely understand where you're coming from (yes, honest) and it comes back to building knowledge and understanding and that has to include simple basic terminology.

 

It is far easier to do that in book than on the 'net/in a forum.  And,  especially as a thread grows, it is probably easier to refer back and re-read in a book than in a thread where you're trying to delve out the particular post you need.

[asmay2002]

We are on page 10 of this thread already and I'm not sure much of it is of any help for somone trying to signal a layout.  Many (most?) layouts will be a single station within one block. What goes on outside that block may or may not be relevant but probably won't (I think) affect where most of the signals are placed. What (I think) a modeller needs is a logical procedure to go through of how and where to place signals and what they need to consider on the way through this process (there must be one). 

Edited September 9, 2017 by asmay2002

[The Johnster]

Absolutely agree, asmay, but it's harder than it looks.  I know, I tried.  And failed.

 

For modellers who want to provide semaphore signals on their layouts and don't quite know how to, and as an extremely gross and highly inaccurate oversimplification, stop signals need to be placed on running lines where they will protect conflicting movements, level crossings, and the entrance to the next block section.  They also need to be where they will protect the exits from sidings and yards, but not, for example on every road in a yard where movements are controlled by handsignals, so the difference between running lines and sidings needs to be understood at a simple level.

 

There needs to be a basic understanding of what interlocking is, what it does, and why, and a basic awareness of what each type of signal looks like, including shunting and ground 'dummy' (GW/WR parlance) signals, also what they do, and why.

 

A similar body of information, grossly simplified and inaccurate as it may have to be if it is simple, needs to be available for those using 'modern' MAS colour light type signalling, in which many of the principles are similar but the actual practice is different.

 

In practice, my contention that an entry level modeller with no railway background does not need to know jargon, block regulations, or the precise meaning of 'in rear' or 'in advance', just where the signals go, proved impossible for me to describe without invoking jargon, block regulations, and the whole shebang; I shot myself in the foot.  I still believe that entry level modellers do not need to know the whole story until they are ready to learn it for themselves out of curiosity, but how to provide them with basic information without having to go through the whole master's degree course has defeated me; I retire hors de combat.  It probably needs a book, but I'm not going to write it.

[RailWest]

Many (most?) layouts will be a single station within one block. 

Pardon?

 

The only 'block' in signalling terms would be a 'block section' and I would suggest that most layouts would lie outside of a block section - to be more precise, outside of one block section if a terminus, outside/between two block sections if a through station. 

[MarkC]

OT, but worth a thought

 

You think signalling terminology is tricky, be grateful you're not explaining the rules of cricket...

 

The Rules of Cricket

You have two sides, one out in the field and one in.
Each man that's in the side that's in goes out, and when he's out he comes in and the next man goes in until he's out.
When they are all out, the side that's out comes in and the side thats been in goes out and tries to get those coming in, out.
Sometimes you get men still in and not out.
When a man goes out to go in, the men who are out try to get him out, and when he is out he goes in and the next man in goes out and goes in.
There are two men called umpires who stay out all the time and they decide when the men who are in are out.
When both sides have been in and all the men have out, and both sides have been out twice after all the men have been in, including those who are not out, that is the end of the game!

 

Howzat!

[asmay2002]

Pardon?

 

The only 'block' in signalling terms would be a 'block section' and I would suggest that most layouts would lie outside of a block section - to be more precise, outside of one block section if a terminus, outside/between two block sections if a through station. 

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

[Grovenor]

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

There is no question in your post, just a statement!

Regards

[Junctionmad]

So we agree it's possible , but none will write it. Ok.

[Junctionmad]

So what does the list in Post 198 do apart from exactly that? (although it does, inevitably, have to relate to block working and railway terminology in some respects in order to make complete sense or why else would there be stop signals a long way from any points).

 

And how else might you be able you make sense of something like this arrangement of stop signals at Ledbury (picture at top right of the linked page) -

 

http://www.roscalen.com/signals/Ledbury/

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

Edited September 9, 2017 by Junctionmad

[Clive Mortimore]

OT, but worth a thought

 

You think signalling terminology is tricky, be grateful you're not explaining the rules of cricket...

 

The Rules of Cricket

You have two sides, one out in the field and one in.

Each man that's in the side that's in goes out, and when he's out he comes in and the next man goes in until he's out.

When they are all out, the side that's out comes in and the side thats been in goes out and tries to get those coming in, out.

Sometimes you get men still in and not out.

When a man goes out to go in, the men who are out try to get him out, and when he is out he goes in and the next man in goes out and goes in.

There are two men called umpires who stay out all the time and they decide when the men who are in are out.

When both sides have been in and all the men have out, and both sides have been out twice after all the men have been in, including those who are not out, that is the end of the game!

 

Howzat!

Hi Mark

 

With all those ins and outs I started to dance the Hokey-Coky :danced:

[Clive Mortimore]

We are on page 10 of this thread already and I'm not sure much of it is of any help for somone trying to signal a layout.  Many (most?) layouts will be a single station within one block. What goes on outside that block may or may not be relevant but probably won't (I think) affect where most of the signals are placed. What (I think) a modeller needs is a logical procedure to go through of how and where to place signals and what they need to consider on the way through this process (there must be one). 

HI Asmay

 

I understood what you meant.

 

I fully agree most of us will only be modelling what is under the control of one signal box, so we need to know where to place the signals. Now I also appreciate  where the "professionals" are coming from, to understand where and why certain signals are where they are then a basic knowledge of block working is needed. That is why I posted fig 1 from "Railway Signalling and Communication" back in post 34. An illustration from a book by professionals for professionals, not a children's book "Noddy plays in the signal box". But a few post after it, it was poo-pooed because the GWR didn't always leave enough room for the their trains between the last potential place of a collision and the starter signal so needed permission of the box in advance to enter their block section to shunt, an unnecessary complication which some of the professionals seem hell bent on  throwing into this thread.

Edited September 9, 2017 by Clive Mortimore

[Dave John]

Well, as my mother was fond of saying, the road to hell is paved with good intentions. 

 

Perhaps as a tentative suggestion it might be an idea to restart the thread. Look at the signals, both semaphore and lights which are available off the shelf to modellers. Then suggest via some practical examples the way in which they could be used in a manner which would, within the limits of an average model railway, control the movements of trains within the context of a model railway. 

 

Surely the idea is to get folk going with signalling, which was I think the ops concept.  Its a complex subject and of course is both time and location specific. But getting started and thinking about the absolute details on a case by case basis might be a practical approach ? 

 

Just a thought. 

[RailWest]

>>>But a few post after it, it was poo-pooed because the GWR didn't always leave enough room for the their trains between the last potential place of a collision and the starter signal so needed permission of the box in advance to enter their block section to shunt, an unnecessary complication which some of the professionals seem hell bent on  throwing into this thread.....

 

With respect, such an unwarranted jibe IMHO shows a lack of understanding of exactly why there are some of use who caution that "it is not as simple as...".

 

There were many places (on the GWR, if you want to be specific) where, if you placed the 'section' signal sufficiently far enough away for the longest train to be able to draw clear of a siding or crossover for shunting purposes, the front of the train would have been out-of-sight of the signalman. This might be because of the curvature of the line or an intervening overbridge etc. Now consider the case of a light engine, or perhaps a very short goods train, drawing up to the 'section signal' to await 'LIne Clear' from the box ahead. In the days before the widespread use of track-circuits there would be nothing to remind the signalman of the presence of that engine/train, other than what he could see from his box. Sadly, the inevitable results of occasional human failings was an accident when a second train was signalled into the back of the first. Consequently it became the practice in earlier days to place the 'section signal' in such a location that any engine stood at it could be seen from the signal-box - which is why, in many cases, a shunt-ahead arm became necessary to facilitate shunting.

 

This was not an "unnecessary complication", but an example of adopting what today would be called "safe working practice". The modeller needs to understand that there is more to the correct placing of such a signal than simply the length of the longest train to be shunted.

[Reorte]

This was not an "unnecessary complication", but an example of adopting what today would be called "safe working practice". The modeller needs to understand that there is more to the correct placing of such a signal than simply the length of the longest train to be shunted.

What is essential to make a safe running real railway can be an unncessary complication for the modeller trying to understand the basics. Even if the modeller wants to understand every little aspect all you're going to do is overload him if you try to explain all this in one go; at most have the first post in the thread, the first chapter in the book, not mention anything else at all beyond "there are issues with this that'll be explained later."

Edited September 10, 2017 by Reorte

[Junctionmad]

What is essential to make a safe running real railway can be an unncessary complication for the modeller trying to understand the basics. Even if the modeller wants to understand every little aspect all you're going to do is overload him if you try to explain all this in one go; at most have the first post in the thread, the first chapter in the book, not mention anything else at all beyond "there are issues with this that'll be explained later."

I agree , and this is a failing of the " experts" to relate to " real life " model railways! . Worrying about " sighting distances " or " shunt ahead" when no block exists in a model railway is ridiculous.

 

So to take the previous posters issue , it doesn't matter on a model railway if one is required to " shunt ahead" because the section signal is close , you just do it ! , either by pulling of the signal , or " assuming " the driver has received specific verbal instructions to proceed etc. It's just your imagination. !

 

Hence the futility of " nitpicking " by continuously mentioning situations where the " generality " doesn't apply , as if such specific cases then invalidate the " generality ". For the average modeller such specifics and nitpicking simply don't have relevance and merely serve to confuse rather then enlighten

 

This was not an "unnecessary complication", but an example of adopting what today would be called "safe working practice". The modeller needs to understand that there is more to the correct placing of such a signal than simply the length of the longest train to be shunted.

 

The average modeller with an average fictitious layout , simply doesn't have to understand the specifics you mention , everything is concatenated on a model railway and in reality sighting distances are entirely irrelevant and it's likely signals will be placed well short of the longest trains. In that case modellers will simply ignore blocking back or shunting ahead as these are only really relevant in the context of a functional block system

 

The same approach can be applied to interlocking, what the modellers needs is an understanding of how not to set up conflicting moves , i.e. To avoid obvious howlers. Then the interlocking can be imagined !

 

 

A classic example is my own layout , which is signalled prototypically as it's a model of a real location and hence the semaphores are a facsimile. BUT , distances are severely concaternated , especially between outer and inner homes and starters to advanced starters. Hence I will regularly breech the station limits and in shunting ( especially with the starters ) many trains are too long to shunt without effectively entering the section ahead or in the rear. Hence in reality, while the prototype rarely breached the station limits , I will habitually , hence I have to simply ignore any prototype practices since they don't basically work.

Edited September 10, 2017 by Junctionmad

[big jim]

All I can think about with this thread now is this.....

 

 

Substitute "puppet" with "model railway"

[Flying Pig]

But a few post after it, it was poo-pooed

I do hope you are not poo-pooing a poo-poo.

 

https://youtu.be/QeF1JO7Ki8E

[RailWest]

>>>The average modeller with an average fictitious layout , simply doesn't have to understand the specifics you mention...

 

It all depends what the 'average modeller' (and I put myself firmly in that category!) wants to do/achieve. If he just wants the 'right sort of signals' in 'roughly the right places', then maybe OK. But if - as you say when talking about interlocking' - he wants to avoid obvious howlers, then I would argue that he does need to have a modicum of knowledge of some of the associated issues. 

 

For example - I once saw a very nice layout equipped with all the right signals in all the right places, but.....the layout was for a pre-grouping period, but it used signals of a later type and installed in accordance with practices not introduced until nationalisation. Not a bit of knowledge that the builder might have gleaned simply from reading a 'simple guide to signalling' and looking at a few photographs.

[runs as required]

Oh dear This thread has done a Hard Brexit and lemming-like we've fallen off a cliff with abuse since I last clicked in.

 

About fail safe clearing distances beyond in advance of the Home signal and Clearing points, I can remember sitting in the Restaurant Car of the down 'West Riding' behind a brand new Deltic in 1961, enthusiastically tucking into a hearty breakfast at 100mph.

That is, until we heard a b£**%y Signal Engineer braying loudly with Authority across the aisle that our train had no hope of stopping for more than two Blocks ahead!

It nearly spoilt my kipper.

dh

[MarkC]

Hi Mark

 

With all those ins and outs I started to dance the Hokey-Coky :danced:

 

One aims to please, Clive

 

[The Johnster]

Oh dear This thread has done a Hard Brexit and lemming-like we've fallen off a cliff with abuse since I last clicked in.

 

About fail safe clearing distances beyond in advance of the Home signal and Clearing points, I can remember sitting in the Restaurant Car of the down 'West Riding' behind a brand new Deltic in 1961, enthusiastically tucking into a hearty breakfast at 100mph.

That is, until we heard a b£**%y Signal Engineer braying loudly with Authority across the aisle that our train had no hope of stopping for more than two Blocks ahead!

It nearly spoilt my kipper.

dh

 

 

 

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

[Ray H]

One of the difficulties that a "basic" description will give is that those that follow it may then think that they have become knowledgeable and start to use their so called knowledge to tell others how to signal their layout, a layout which may be more complex than their own.

 

It might be OK if one's misconceptions were limited to ones own layout but it is inevitable that the misconceptions will spread and the signalling of subsequent layouts will be erroneous.

 

There are several users of this forum who believe they have learned enough to class themselves as experts in whatever field, when in fact their knowledge is based on misconceptions and totally inaccurate when passed on.