Signal needed?

[John Donnelly]

As some of you will know from my layout thread, I'm building a model of South Pelaw Junction on the Tyne Dock to Consett Line which, due a slight cockup on my part isn't 100% accurate, and that has presented me with a signalling dilemma...

Below is the Templot plan of the layout and the round circle represents a home signal that was there on the real thing.



The mistake I've made is that the crossover is further away from the signal than it was in real life. In reality, as the crossover was that much closer to the signal, there was also a calling on arm on the post to allow banking locos to pass the home signal before reversing back over the crossover.

On the model, there is more than enough room for a loco to pass the crossover and reverse without going past the home signal so the question is, would there likely still be a calling on arm?

As I understand it, as long as the loco doesn't pass the home signal there would be no need for one but I'm wondering if the arm would be there to allow, should the need arise, for a longer train to pass the crossover and reverse?

John

[grovenor-2685]

Its unlikely that a call on arm would be provided if no regular need for it. Could you not move the signal back closer to the crossover to replicate the prototype operation?

[davebradwell]

Why not just shift the crossover to where it should be? Even if you wrecked it and had to build a new one it would be a small job in the scheme of things. There's bound to be other problems arising from its position.

DaveB

[John Donnelly]

Its unlikely that a call on arm would be provided if no regular need for it. Could you not move the signal back closer to the crossover to replicate the prototype operation?

I could although that would almost be making up a reason for the calling on arm to be there...

[John Donnelly]

Why not just shift the crossover to where it should be? Even if you wrecked it and had to build a new one it would be a small job in the scheme of things. There's bound to be other problems arising from its position.

DaveB

Definitely no other issues with it being in the wrong place, so far as I have been able to ascertain, it was only ever used by banking locos to get them back on the up branch so they could reverse back in to the bankers siding, it being a foot or so in the wrong direction causes no operational problems.

[davebradwell]

........except for the signal!

DaveB

[grovenor-2685]

Its unlikely that a call on arm would be provided if no regular need for it. Could you not move the signal back closer to the crossover to replicate the prototype operation?

I could although that would almost be making up a reason for the calling on arm to be there...

Surely the reason is the prototype you are modelling, if you can't move the crossover then move the signal to keep the correct relationship. But if you are happy not to have a calling on arm then that is fine too, rule 1 applies.

[John Donnelly]

........except for the signal!

You got me!

I'll have to give it some thought, don't really want to move the crossover as I only got the thing fully operational last night!

[John Donnelly]

Surely the reason is the prototype you are modelling, if you can't move the crossover then move the signal to keep the correct relationship. But if you are happy not to have a calling on arm then that is fine too, rule 1 applies.

I may have to go for rule 1. On the prototype, the signal in question is right up against a bridge so moving it might be more jarring that the calling on arm not being there.

[bécasse]

Surely it is a shunt ahead signal rather than calling on. Given that your prototype railway was the NER who were reputed to signal every move that was necessary - and quite a few that weren't - I would be inclined to keep it. One possible "excuse" might be that, on rare occasions, several banking locos coming off shed and needing to reverse over the crossover to reach the bankers' siding simply had to shunt ahead past the main signal. If the box wasn't in the immediate vicinity, such a move couldn't readily be flagged.

[John Donnelly]

Surely it is a shunt ahead signal rather than calling on.

It may well be, you'll have to excuse my lack of the correct terminology, all of this is pretty new to me...

Given that your prototype railway was the NER who were reputed to signal every move that was necessary - and quite a few that weren't - I would be inclined to keep it. One possible "excuse" might be that, on rare occasions, several banking locos coming off shed and needing to reverse over the crossover to reach the bankers' siding simply had to shunt ahead past the main signal. If the box wasn't in the immediate vicinity, such a move couldn't readily be flagged.

Indeed the NER were like that, the box was within sight of the crossover but the move was signalled rather than flagged.

[Martin Wynne]

Hi John,

Leave the Shunt Ahead arm on the signal, but paint the lever in the signal box white. Signal out-of-use after the PW dept. moved the crossover. S&T dept. coming next week to remove the arm.

Martin.

[John Donnelly]

Leave the Shunt Ahead arm on the signal, but paint the lever in the signal box white. Signal out-of-use after the PW dept. moved the crossover. S&T dept. coming next week to remove the arm.

Funny you should say that as, on the prototype both the crossover and the signal were actually moved. My crossover is where it was originally but by the period I am modelling it had been moved further to the left on my plan and the signal moved to where I indicated. When the crossover was where I have modelled it the signal was to the right of the crossover...

John

[John Palmer]

Speaking as one who is attempting to make an accurate scale model of a real station and its surrounds as it was at a particular date, give or take three years or so either side, I think the answer to your dilemma depends a great deal upon how you choose to apply Rule #1. It's clear you have undertaken in-depth research of your chosen prototype to the extent that you are able to pinpoint changes in the track layout. If you leave signal and crossover in their present positions, you will be aware throughout the layout's lifespan that the crossover is wrongly located, given the signal's current position, and I'm assuming that you can't re-locate the signal to its former position because that won't fit with the date/period you have chosen to represent. So the solution to the dilemma that you choose very much depends on whether your interpretation of Rule #1 tolerates subordination of historical accuracy to convenience/time saved by not re-locating the crossover to its correct position.

There's no correct answer to the solution you adopt. I've made a building with a roof that fitted an incorrect assumption I had made about the shape and size of its tiles. By the time I chanced upon a photograph revealing my error, changing the roof to a more accurate representation of the tiles would have caused serious damage to the building as a whole. I keep telling myself that my decision not to change the roof and so avoid causing such damage was the rational and sensible one to make, but even though no-one else will ever be aware of the error I am aware of it, and it still niggles. How far will your knowledge that the crossover is in the wrong place be a gnawing source of continuing dissatisfaction?

[John Donnelly]

Thanks for that John.

Rule 1 is already rather evident at the other end of the layout. By 1970 the track had already been severely rationalised due to the closure of local collieries but, for more operational potential for the layout, I've not removed as much of the track as BR had.

Here's what the other end of the layout looks like:



and here is what the real thing looked like where, as you can see, most of the track on the right of the photo above had already been lifted...


South Pelaw Junction in 1970, photo from Bill Jamieson.

Over the time period that the layout is meant to represent there were even more significant changes to the track layout so I've already accepted that the track plan was never going to be accurate for all of the trains that will run.

With regards to the crossover specifically, I'd already decided it was staying where it was but, allowing for that, I still wanted to make sure that, for where it is, it was signalled correctly.

John