Lynton and Barnstaple - Operations and Development

>>>In general, as you may already be aware the Lower Quadrant signals were more common originally....

For a long time LQ signals were the only type of semaphore signals in the UK (other than some 'cross bar' shunt signals which rotated horixontally). Apart from a brief experiment with 3-position signals, which were done as UQ to follow their American origin, UQ signals were not adopted until that experiment ended (to avoid any confusion) in the late 1920s. Even then many LQ arms remained in use well into the 1960s.

>>>With Lower Quadrant signals they require extra balance weights at the signal post in order to ensure the signal arm lifts back up to to the horizontal position in the event of a wire failure.

Sorry, but I must disagree with that fallacy. It was a BoT requirement that LQ arms had to be able to return to danger under their own weight (hence the heavy spectacle plate casting). After all, what else would have happened if the down-rod between the arm and the weight lever broke? The weight lever did help of course to bring the arm back to danger more quickly, but its primary purpose was/is to pull in the slack in the signal-wire once the lever in the signal-box frame has been replaced.

 

I'm not sure that I understand the question ;-) Are you talking about the original 1898-1935 railway or the current-day line?

If the former, then all L&BR signals were always lower-quadrant with the sole exception of the Up Home at Woody Bay, which was renewed by the SR in 1934 in the new contemporary standard of upper-quadrant arms.

If the latter, then the answer is simply that the initial restoration at Woody Bay used whatever was available - in this case an UQ arm if I recall for the Down Home - until such time as the correct LQ arm could be sourced.

 

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I hear what you say, but surely making an extra heavy casting for what could otherwise be a lightweight spectacle plate is 'adding extra balance weights'

After all, even UQ signals need some balance weights to overcome the drag of the wire run.

 

This is starting to remind me of:

 

With respect, but the weights on a weight lever have nothing to do with 'balance'. The purpose of the weight lever is to pull in the signal wire slack and therefore must be weighted accordingly.

If the down-rod broke on an UQ arm then the arm would return to danger, but there would be nothing to pull in the wire without the weights on the weight lever, same with a LQ arm. So there are no 'extra' weights on the weight lever, just the amount necessary to do its job.

With a LQ arm, clearly there must be more weight to the right of the pivot than to the left, in order for the arm to return to danger by itself. Therefore whatever exists to the right of the pivot (which is usually the spectacle casting) must be made heavy enough to fulfil that purpose. Again it is not 'extra' weight, simply the weight needed to fulfil the requirement.

 

Glad that we've got up and down sorted out (not)! Now that we are in the twenty-first century perhaps it is time to consign it all to history. As far as the L&BR is concerned surely all we need is Barnstaple direction or Lynton direction? Signalling buffs might well continue as consenting adults of course, but ordinary mortals will undoubtedly prefer to know where they are going!

 

In Sweden lower quadrant signals were banned 100 years ago. This because the risk of ice on the wing rendering the counter weight insufficient.
But the term "lowering the signal" has remained as an unofficial term used as long as we had semaphore signals, i.e. still on preserved railways.

 

As a point of order, ‘ordinary mortals’ have always had things like timetables and signposts and destination boards to tell them where they are going. Signalling ‘buffs’ can do what they like but the railway itself needs some kind of official designation as these are used not just on signal box diagrams but in all sorts of paperwork. You can call the two directions whatever you like but there does need to be some sort of official name for them.

Before we get back on topic... which current UK railway doesn’t use ‘up’ and ‘down’ at all?


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Before we finally leave the discussion of signals: why do we call them upper or lower quadrant, rather than octant, considering that they move by only about 45°?

 

Like slotted post signals were banned here for a similar reason. Snow could get packed in the slot, preventing movement.
Does anyone recall which accident was caused by this?

 

Possibly because I’m days past they moved over a much larger arc (think of a GNR somersault signal, or a slotted post, where the signal is more or less vertical when off.
@RailWest wil know better, but I think in the very early days of signalling there were time installations that used horizontal for danger; 45 degrees down for caution s as me fully down (and hidden) for proceed - that would have been in time-interval days when, without a signal post, the Bobby would have given similar indications with flags.

Tom

 

Abotts Ripton, 21st Jan. 1876. The up Flying Scotsman ran into the rear of the proceeding coal train which was shunting clear to let it past. Signals had frozen in the clear position as a result of a severe snow storm. A down Leeds express then ran into the wreckage. Thirteen people died.

Interestingly slotted signals do not seemed to have been banned. They were extensively used by the former North Eastern Railway and survived in use on BR at least until the late 1970s.

Peter

 

I think the last one went late 1980s/early 1990s - I'm sure I recall seeing it marked in the railway press when I first started taking magazines. On the Skegness line?

 

Thanks for that, Peter. Yes there was still a lot of slotted posts around after that. Certainly on the LBSCR well into the 1890s, although the only picture of one in more modern times I can recall, was at the mouth of Newhaven Harbour, and I'm pretty sure that controlled shipping, rather than trains on the West Harbour branch.

 

You’ve sent me scuttling back to the accident report for an afternoon’s reading ...

https://www.railwaysarchive.co.uk/documents/BoT_AbbottsRipton1876.pdf

(One of those vast sprawling accidents with lots going on in different places and a whole series of learning points and things being done very differently then than later came to be common).

Tom

 

There are a few in preservation. NYMR have several, as do the Aln Valley, so there must be allowances in signalling design protocol

 

I've often wished that the Bluebell could have recreated a couple of examples at Sheffield Park, seeing as the period portrayed is the 1880s, I'd just figured that they were no longer legal. Interesting.
Theres some serious thread drift going on here, though!

 

I think you might be confusing sumersault signals, as used on the GN, among other railways, with slotted post signals as preferred by the NER. Both survived in use until recent years. This is the ex GNR somersault signal outside the NRM (and now starting to look the worse for wear after 45 years there):-

while this is a NER slotted signal in the foyer of York station


The blurb at it's base tells that it was the up distant signal at Haxby on the Scarborough line and when replaced in 1984 it was the last of its type on a main passenger line.

Peter

 

I believe the continued use of slotted post signals was because, unlike in very early days, they no longer had an indication in which they were completely hidden within the post (and liable to get frozen in place in bad weather). So by time they disappeared, they were operationally no different from any other LQ semaphore, except the the pivot was within a slot rather than on the face of a solid signal post.

Tom

 

Correction noted with thanks