Help with basic signalling please

[45157]

HI all

 

I am trying to figure out the basic signalling arrangement for my imaginary ex GNSR layout (the big problem with non-prototypical stuff)

 

 

The layout is shown above.

I started to base it (space permitting) on Macduff but soon realised I had nothing like enough room and it has had to be "cobbled up" to fit the space available.

Although Macduff did have a Signal Box I know from photographs that the loco release from the platform was by local ground levers.

 

My big "need to know" is really ground signalling and the positioning of "normal" signals.

 

I fully accept that the smaller railways varied a great deal and do not expect a definitive answer from anyone, but, I just don't want to make any stupid mistakes as I know nothing about signalling etc so even during my own research, I am not really sure what I am looking for.

 

Thanking you all in anticipation.

 

regards

Stewart

[Ray H]

My initial guess would be:

• A running signal for departures from the platform
• A running signal - the Home signal, possibly with two arms, for arrivals at the platform and (optionally) arrivals into the goods yard. The latter may be replaced by a shunt signal.
• A shunt signal adjacent to the Home signal, to allow locos to run into an occupied platform (e.g. after running round) although this move could be controlled by handsignal from the signal box.
• A shunt or running signal controlling exit from the yard. The running signal is probably only required if a section signal, which would be beyond your bridge, is not provided. If you have a running signal then you'd probably need a shunt signal to route trains to the headshunt. If you have a shunt signal that would either cover both the route to the main line and the route to the headshunt or it would need two signals, one for each route.

Depending on the length of your headshunt, you may need a signal controlling exit therefrom to stop collisions on the loop.

 

Goes and hides in the equipment room under the signalbox as I suspect I've got it completely wrong.

 

 

[Guest stuartp]

Somewhere at home in a book there's a photo of Macduff taken from the top of the adjacent hill during the 1960 railtour, which I'm pretty sure shows most of the layout. I'm also pretty sure it consists of two running signals - one in and one out, and maybe a dolly controlling the exit from the yard, everything else being done by handsignals. Unusually for me I can remember exactly which book* - I will check when I get home and sketch the signals. It shouldn't be too difficult to adapt real to model without taking too many liberties.

 

No-one could ever accuse the GNSR of oversignalling a location.

 

(*Scottish Branchlines 1955-65 by CJ Gammell if someone would like to beat me to it).

 

[Edit - two signals alright, but one on the platform line and one on the bay. Home signal for arriving trains is out of shot]

[The Stationmaster]

I know little about the GNofSR but suspect it to be little different from most of the less well off Railways- so not much in the signalling stakes! The only picture I can find of Macduff is from 1949 and doesn't show anything beyond the signalbox/locoshed roof going away from the station - the only signals visible are starters for each platform and the release crossover is definitely not worked from the signalbox.

For you layout there would, I think, be a ground signal controlling the exit from the loop/sidings - it would only be cleared when teh points are set towards the 'main' line and would be ignored for any move towards the headshunt. The one area I can't be sure of is the Home Signal - definitely a running arm for the move to the platform but I don't know if it would have either a miniature arm or co-located ground signal to read into the loop and sidings. Finally I understand that the GNSR used Stevens as its signalling contractor and thus had that company's distinctive 'flap' type ground signals.

[45157]

Many thanks Ray, Stuart and Mike for the replies so far.

 

I think I probably have most of the published photographs of Macduff (please prove me wrong as I have yet to obtain the station entrance) and as a member of the GNoSR a goodly ammount of information and photographs.

My real problem is a lack of practical knowledge of how signalling is meant to work.

I have plenty of photographs of signal installations throughout the GNoSR area for various periods in time but there seems to be no hard and fast "rules" as such, to how a "typical" location would be treated.

 

So, although I could probably take examples of most of the features I would like to see on my train set (ground signals, point rodding etc) I don't want to make it look stupid because of my lack of knowledge.

I am certainly not a "accuracy fanatic" but would like it to remain within the realms of possibility (although some of the stock waiting in the "to be built" drawers will push that to the limit !!) but deep down I think I know that in this case "less is more" if I want my non prototype layout to remain realistic.

 

A little extra info ... (1) The head shunt is very short, really just to save a loco from needing to continually block the passenger line when shunting the yard.

(2) It should be possible for a passenger train to be signalled to arrive and/or depart while the yard is being shunted by a second loco.

(3) I simply do not have the room to model any of the "station entry" signalling.

Thanks again

 

regards

Stewart

[Kris]

I think that you could get away with 1 signal on the platform (or just off the end) as a starter, and a ground signal controlling the exit from the goods yard to the main. The home signal would likely be off scene, beyond the bridge.

[TheSignalEngineer]

I don't know if the GNoS used yellow shunt signals but if they did one would be appropriate, cleared only for moves onto the main line, at the exit points from the sidings assuming there was a short neck to a stop block.

There would be a main signal to control the exit from the platform line, probably between the signal box and water tower, so an engine taking water would still be within the signal.

The Home signal reading into the station or sidings would be beyond the bridge, as it would not be visible to approaching trains if it were on the layout. The Starting signal into the Single Line Section would be further out beyound the Home.

As you said in the OP, a Ground Frame would be used for the engine release crossover.

 

The GNoS website has an old picture of MacDuff, but the visible signalling is sparse except for a main running signal coming in. Go to GNSRA Website for more details.

[TheSignalEngineer]

This shows a few more pictures, including the platform starters, and a ground signal at the sidings exit points Railscot MacDuff

[The Stationmaster]

I don't know if the GNoS used yellow shunt signals but if they did one would be appropriate, cleared only for moves onto the main line, at the exit points from the sidings assuming there was a short neck to a stop block.

 

 

 

 

'Yellow shunt signals did not appear in the Rule Books until the late 1920s and seem to be a new invention from that time - when a lot of revisions were made to the meaning of the various Pre-Grouping subsidiary and shunting signals etc. For example a number of changes of meaning were made to some subsidiary signals on the Highland.

the situation of ground signals which could only clear for one route was a common feature of the early designs of independent signal presumably stemming directly form the earlier signals which worked in conjunction with points.

 

[Guest stuartp]

From the links supplied above, CJG's pic referred to earlier, and another Casserley one I found, I offer this:

 

 

Arriving from the left - the (off stage) home signal has two arms at equal height, left hand for the platform line and right-hand for the loop. Whichever route you take your fireman needs to drop off the token on the way past the box. Other companies would have used a bracketed miniature arm for the loop, or at least put the arm on a lower doll to show its lower status.

 

Departing - one starting signal on the platform, either as drawn or as shown by the arrow if you prefer, but not if the view of it would be obscured by the water tower. There might have been an advanced starter as suggested by Signal Engineer (also off stage), I don't have a pic looking in that direction. Again, you need to collect the token on the way past the box.

 

The loop. Hmm. Stephens drop flap as suggested, MSE do a working one. A vertical red board, it tips forwards edge on to the driver when clear. When cleared it allows you to proceed as far as the advanced starter if there was one, any further than that and you need to be in posession of the token.

 

If there was no advanced starter then I'm not so sure. Either (a) the ground signal reads straight out into the token section and there's nothing to stop you going all the way to the next block post provided you collect the token on the way past, or (b.) it allows you to proceed as far as necessary in order to shunt back into the platform line and depart on the authority of the platform starter. (Anybody know for sure ?). I suspect that if option 'b' applied then it only applied when anyone official was watching unless the interlocking required it.

 

Points marked 'H' are hand worked, those marked 'G' are worked from a ground frame near the buffer stops. Red line indicates a facing point lock.

 

You can arrive into the platform line with a goods train shut inside in the yard i.e. with the road set for the platform and the line clear to the buffer stops, and you can depart from the yard with a train in the platform provided option 'b' above doesn't apply, or shunt in the yard using the headshunt. You can shunt onto vehicles in the platform line passing signals at danger on the authority of handsignals from the 'box, and you can shunt your goods train out of the loop onto the dock siding to clear the loop if your passenger loco needs to run round.

 

Experts please feel free to tear this to bits, but hopefully it stays true to the original Macduff plan with a bit of supposition. MSE also do the bits for your one visible main running signal if you want the proper Stevens signals, they survived until closure.

 

[edited for muppetry]

[TheSignalEngineer]

The Railscot site picture of Gordon Highlander arriving has a ground signal at the exit points. With the GNoS reluctance to put in any signals, there may even have been a Stevens Points Position Indicator there at one time.

[Guest stuartp]

The Railscot site picture of Gordon Highlander arriving has a ground signal at the exit points. With the GNoS reluctance to put in any signals, there may even have been a Stevens Points Position Indicator there at one time.

 

Thanks. I not only missed that, despite looking at the link I missed your reference to it two posts up . There is indeed someone stood in front of it on my pic.

[45157]

Thank you to everyone who replied, and to Stuart for the plan, very useful.

The links were also very useful, I discovered a view of the Macduff water tower I had not seen before.

 

I think I will need to attend a lecture or something on the basics of British Signalling and do a bit more research on what sort of changes, if any, were made in the area by the LNER and British Railways up to my late fifties period.

 

The train set is "on hold" at the moment as I may have to consider a rebuild of the baseboards to a more managable formation as I am now physically unable to spend any length of time underneath looking up so need to have an easily dismantled system while construction and detailing takes place.

Because it is a stay at home layout I used whatever wood I had with no regard to lightness (or any future back problems) and I simply cannot manhandle it on my own, so it's back to the drawing board I think (too cold in the garage at the moment anyway)

 

Many thanks again, this really is a first class forum.

 

regards

Stewart

[MarkAustin]

I think that you would need the advance starter, as, without it, you couldn't shunt the yard or run round a train without offering a train up to the next signal box, with all the attendant hassle. Having the advanced starter keeps everytghing withing the station limits.

[Guest stuartp]

Not sure. G&SWR practice (with which I'm more familiar than GNoSR but who were equally thrifty and who also used Stevens) would not have an advanced starter just for this purpose, the run round would be accomplished by withdrawing the token and shunting into the block section. The only additional hassle is that the chap at the next box has to get up to answer the 'shunt into fwd section' and 'shunt withdrawn' bell signals, and can't offer you another train in between times.

 

Where you might get an advanced starter (and an outer home) would be where traffic was frequent enough to need to accept a train with one already shunting at the terminus, and shutting it inside the loop was not an option.

 

However, without the advanced starter the ground signal in the yard is reading directly into a block section, and I'm not sure how permissible that would have been particularly as they've gone to the trouble of providing a full-sized arm for the opposing movement off the single line onto what is effectively a goods line. It certainly wouldn't have been permitted in later years (if re-signalled), a miniature arm would have been provided at least.

 

... a bit more research on what sort of changes, if any, were made in the area by the LNER and British Railways up to my late fifties period.

 

Here's one option:

 

 

This might be a bit over-signalled. The full-sized arm reading into the loop has been replaced with a minature arm on a bracket, likewise the signal reading out of the loop has been replaced with another miniature arm (if no advanced starter) or a yellow disc (if there is an advanced starter). You need to ask Micknich2003 or Beast60666 which of these is more likely for LNER practice. I've drawn a calling-on arm under the home to allow you to shunt into an occupied platform but I suspect this might be overkill. Same size as the miniature arm but with a horizontal white stripe, it allows you to pass the main arm at Danger to attach or detach.

 

You can do all the visible parts of this with one Ratio signal kit, either the LNER lattice post versions or the LMS round post ones - these vary only in detail from Railway Signalling Co round posts which the LNER also used. Even if you subsequently replace them with nice soldered ones they make good place-holders at less than a tenner a set. Or you could just leave the GNoSR arrangements in place - the prototype did !

[45157]

I think that you would need the advance starter, as, without it, you couldn't shunt the yard or run round a train without offering a train up to the next signal box, with all the attendant hassle. Having the advanced starter keeps everytghing withing the station limits.

 

 

Thank you for that explanation, I think I am beginning to get a grip of this now.

 

regards

Stewart

[45157]

Not sure. G&SWR practice (with which I'm more familiar than GNoSR but who were equally thrifty and who also used Stevens) would not have an advanced starter just for this purpose, the run round would be accomplished by withdrawing the token and shunting into the block section. The only additional hassle is that the chap at the next box has to get up to answer the 'shunt into fwd section' and 'shunt withdrawn' bell signals, and can't offer you another train in between times.

 

Where you might get an advanced starter (and an outer home) would be where traffic was frequent enough to need to accept a train with one already shunting at the terminus, and shutting it inside the loop was not an option.

 

However, without the advanced starter the ground signal in the yard is reading directly into a block section, and I'm not sure how permissible that would have been particularly as they've gone to the trouble of providing a full-sized arm for the opposing movement off the single line onto what is effectively a goods line. It certainly wouldn't have been permitted in later years (if re-signalled), a miniature arm would have been provided at least.

 

 

 

Here's one option:

 

 

This might be a bit over-signalled. The full-sized arm reading into the loop has been replaced with a minature arm on a bracket, likewise the signal reading out of the loop has been replaced with another miniature arm (if no advanced starter) or a yellow disc (if there is an advanced starter). You need to ask Micknich2003 or Beast60666 which of these is more likely for LNER practice. I've drawn a calling-on arm under the home to allow you to shunt into an occupied platform but I suspect this might be overkill. Same size as the miniature arm but with a horizontal white stripe, it allows you to pass the main arm at Danger to attach or detach.

 

You can do all the visible parts of this with one Ratio signal kit, either the LNER lattice post versions or the LMS round post ones - these vary only in detail from Railway Signalling Co round posts which the LNER also used. Even if you subsequently replace them with nice soldered ones they make good place-holders at less than a tenner a set. Or you could just leave the GNoSR arrangements in place - the prototype did !

 

When I asked the original question I didn't dare hope for such a detailed and easy to understand explanation, thank you indeed.

That the diagram may or may not be questioned is something I can happily live with for my non-prototype location, what was bothering me was going down the complete nonsense path with signals and point rodding placed where I thought they looked best (or were easiest to fit)

Apart from the signal wires, it looks like the only rodding detail coming from the box will be the facing point and its locking mechanism.

 

Thanks again for all the help, it is very much appreciated.

 

regards

Stewart

[PWSlack]

Back to basics.

 

Before spraying signals everywhere, the question of how the line is operated needs to be answered. If this is a branch terminus operated under the One Engine In Steam [OES] method, then signals are unneccessary: what is labelled as a "signal box" is in fact then a "ground frame", with the levers being released by a key on the Train Staff. On arrival at the terminus, the fireman or the guard inserts the train staff into a lock on the King lever, operates the frame, and directs all movements using hand signals. The departing train is then made-up in the passenger platform line, the frame locked, and the train proceeds on its merry way with the Staff on the engine.

 

And it could be an OES operation - after all, there's no loco shed at this terminus.

 

Five levers should be enough [King, Crossover FPL, Crossover points, Crossover FPL, Crossover points].

 

And not a signalman in sight.

[Guest stuartp]

Back to basics...

 

It's based on a truncated version of Macduff, so is the signalling. As backstories go how much more basic than (almost) copying the prototype do you want ? The only bit we're not sure about is whether there was an advanced starter. Yes, it could be operated as OES but the prototype was fully signalled until closure despite being goods only for a long time.

 

I did suggest the LNER version might be a bit overdone, particularly the use of a calling on arm. Maybe you could suggest examples one way or the other, preferably based on re-signalled GNoSR locations to prove me right or wrong ? Or go search for a photo of Macduff looking away from the terminus so we can solve the mystery of the advanced starter once and for all.

[The Stationmaster]

Back to basics.

 

Before spraying signals everywhere, the question of how the line is operated needs to be answered. If this is a branch terminus operated under the One Engine In Steam [OES]method, then signals are unneccessary: what is labelled as a "signal box" is in fact then a "ground frame", with the levers being released by a key on the Train Staff.

 

And it could be an OES operation - after all, there's no loco shed at this terminus.

 

 

I'm puzzled as to what difference results from the presence, or otherwise, of an engine shed when it comes to the method of working used on a line. Perhaps you could explain?

(Incidentally the arrangement you propose for a central ground frame, i.e. remotely operating points without fixed signal protection, would not usually have been acceptable as some of the points are remote from the lever frame operating them. And if the frame is released by the train staff why would it need a King Lever?) With due apologies to the OP for comments which don't really relate to his query.

[PWSlack]

.....what difference results from the presence, or otherwise, of an engine shed when it comes to the method of working used on a line....

 

Simples!

 

If the engine berthed at a shed at a terminus operated under OES were to be unavailable for operation, then the Train Staff would need to travel on foot or by road vehicle to the last-station-but-one on the line for the replacement engine to arrive from there and pick up the duties of the failed engine, which costs time.

 

In the absence of a signalman at the terminus, where is the Train Staff kept overnight under OES <rhetorical question>?

 

If an engine were to assist a train engine to an OES terminus and be left there while the train engine returns to the last-station-but-one, then the absence of the Train Staff at the terminus would render the assisting engine's presence there quite useless, as there is nothing much it could do in the absence of the Staff being available to unlock the frame. Rather than an engine, a horse or a pinch bar would be a more likely piece of equipment to be found - lower capital investment and operating costs and the redundant assiting engine could be better deployed elsewhere!

 

Which is sort-of-why the method is called One Engine In Steam. There are no conflicting train movements that might possibly require a signalman and signals.

 

...if the frame is released by the train staff why would it need a King Lever?....

 

Because there are two facing point lock [FPL] levers on a single 5-lever frame for the track layout as currently conceived - one for the platform end crossover and one for the yard release crossover for the junctions on the passenger line - and there is only one train Staff. There would likely be only be one Annet's Lock on a single Ground Frame installation. One King lever would release two FPL levers, hence 5 levers in total. It's either that or fit two Annet's Locks, one each to the FPL levers of a four-lever frame - feasible though less likely to have occurred on the prototype.

 

Slightly different concept - if the OP were to demolish the ground frame hut and replace it with two separate frames, one for the engine release crossover and close to it and one for the yard exit crossover and close to it, then both frames would have an Annet's Lock, which means that each frame would need only two levers: one for the combined Annet's lock and FPL, and the other for the points. That is the way it is currently done at Dufftown on the Keith & Dufftown Railway - incidentally once part of the GNoSR system too.

 

As always, it pays the modeller to study the prototype. The opportunities are there - many heritage railways follow traditional operating practices and their volunteers are always keen to answer questions from curious students.

[Guest stuartp]

As always, it pays the modeller to study the prototype.

 

Which, funnily enough, was exactly what we did ...

[The Stationmaster]

Which, funnily enough, was exactly what we did ...

 

 

 

 

 

[45157]

From photographs I have, there was no advanced starter at Macduff, just a platform mounted signal for the "main" platform and another between the platform end and the signal box for the bay.

Entering the station (outside the scope of the model) there was a gantry with three home signals.

There were at least two facing point locks but I will need to do some more detailed study.

Rather than trying to figure out what might have been done should such a location been built, I think, as suggested, I will just copy Macduff and just leave out what I did not have room for.

 

I think a nice summer break in or around Dufftown will have to be discussed in the near future.

 

Thank you again for all who took the trouble to reply, it was much appreciated.

 

A Happy and Prosperous New Year to all.

 

regards

Stewart

[The Stationmaster]

The Stationmaster asked .. .....what difference results from the presence, or otherwise, of an engine shed when it comes to the method of working used on a line....

Simples!

If the engine berthed at a shed at a terminus operated under OES were to be unavailable for operation, then the Train Staff would need to travel on foot or by road vehicle to the last-station-but-one on the line for the replacement engine to arrive from there and pick up the duties of the failed engine, which costs time.

 

It is then perhaps rather unfortunate then that the GWR - to name but one Company - engaged in the apparently unfortunate habit of siting engine sheds, and stabling engines overnight, at the end of branchlines worked under 'One Engine In Steam' Regulations. Yes it could create a problem if the branch loco failed but it seems those with experience of such matters didn't consider that to be a major problem otherwise they would no doubt have closed a number of loco sheds and moved them to the other end of the line? BTW as a matter of technical detail the train staff would need to be taken to the other end of the OES section, not necessarily 'the last-station-but-one on the line' .

 

In the absence of a signalman at the terminus, where is the Train Staff kept overnight under OES <rhetorical question>?

 

Numerous potential answers to that as there was never any specific requirement in the Regulations for the staff to be left in possession of a Signalman, plenty of other 'secure places' (no doubt on occasion including loco toolboxes).

 

 

If an engine were to assist a train engine to an OES terminus and be left there while the train engine returns to the last-station-but-one, then the absence of the Train Staff at the terminus would render the assisting engine's presence there quite useless, as there is nothing much it could do in the absence of the Staff being available to unlock the frame. Rather than an engine, a horse or a pinch bar would be a more likely piece of equipment to be found - lower capital investment and operating costs and the redundant assiting engine could be better deployed elsewhere!

 

I must admit to being puzzled - if it was necessary to assist the train engine in order to get to the terminus how would it manage to get back along the branch without further assistance? And why would anyone want to leave the assisting engine at the terminus.

 

 

Which is sort-of-why the method is called One Engine In Steam. There are no conflicting train movements that might possibly require a signalman and signals.

 

But there could be if there are two engines and one of them is left at the terminus as you just suggested.

 

 

Because there are two facing point lock [FPL] levers on a single 5-lever frame for the track layout as currently conceived - one for the platform end crossover and one for the yard release crossover for the junctions on the passenger line - and there is only one train Staff. There would likely be only be one Annet's Lock on a single Ground Frame installation. One King lever would release two FPL levers, hence 5 levers in total. It's either that or fit two Annet's Locks, one each to the FPL levers of a four-lever frame - feasible though less likely to have occurred on the prototype.

 

I'm now even more puzzled having known ground frames with a lot more than 4 four levers that were released by a single Annet's Lock (which in several cases locked two FPLs). The simple fact is that having the levers grouped in the way you described makes them remote from the points they control and that was not normally acceptable unless fixed signals were provided and even if they were grouped a King Lever was not needed.

 

Slightly different concept - if the OP were to demolish the ground frame hut and replace it with two separate frames, one for the engine release crossover and close to it and one for the yard exit crossover and close to it, then both frames would have an Annet's Lock, which means that each frame would need only two levers: one for the combined Annet's lock and FPL, and the other for the points. That is the way it is currently done at Dufftown on the Keith & Dufftown Railway - incidentally once part of the GNoSR system too.

 

Yes - if done with ground frames that is the way it should be done but you seem to be missing the point that the question was about the way it was actually done at Macduff, or possibly a similar location. The answers - various - from several sources who did a bit of investigation was to give the best information about the way it appeared to have been done, and not about what they happened to thing was the way they might have done it. Looking at the arrangements as they are today at such a location is probably of minimal relevance to the way it was done several ownership regimes and economy drives previously.

 

As always, it pays the modeller to study the prototype. The opportunities are there - many heritage railways follow traditional operating practices and their volunteers are always keen to answer questions from curious students.

 

 

Regrettably there is very little, if any, of the prototype left to study when it comes to such things as the way Pre-Grouping Companies signalled just about anything - let alone minor branch termini. We have to rely on archives, illustrations, and hopefully accurate articles and books to tell us about that which we can no longer see. And - always a point for the wary - in many cases the operating and signalling practices on preserved railways differ considerably from what was there when the line was in even its final BR operational state let alone what was there, say, 40 years before that. Similarly in some cases 'traditional operating practices' are not at all what many 'preserved'/tourist etc railways need - or can work to - nowadays, as I have found when auditing some of them or assessing their operational safety standards because things have changed enormously under recent legislation.