What do Theatre Boxes display?

[Rugd1022]

22 hours ago, keefer said:

@Rugd1022 So the Dudding Hill line is still semaphore then, Nidge?

Have watched a lot of cab-ride videos of the area (admittedly filmed a few years ago now) and while the NLL/WLL have colourlights and electrification for their modern trains, the DH line still looked like a '60s line with its mechanical 'boxes and semaphores.

Does it see much traffic these days or is it still a kind of 'forgotten' alternative route?

 

Still a mix of semaphores and colour lights semaphore Keefer - here's a (very) quick sketch of the route with Acton Wells on the left and Dudding Hill on the right...

 

 

 

There is still plenty of traffic using as it's a vital north to south connection in that part of London.

 

 

 

Edited December 8, 2023 by Rugd1022

[The Stationmaster]

23 minutes ago, Pacific231G said:

Indeed (though I didn't know it could also apply to a junction between two single lines) I assume this was to avoid a facing crossover that in principle could put a train on the wrong line. Yeovil Town was odd though (AFAIK) by using the up platform for down departures on the branch rather than having a bay. I'm guessing that the Yeovil Town shuttle was an autotrain.

Yeovil Pen Mill wasn't alone in using a through platform line instead of a bay for reversing passenger trains.  As part of their journey it happened at Twyford on the GWML where through trains between Reading and Henley, and return, reversed on the Up Relief Line (there was no access between the branch bay and the Relief Lines)

Edited December 8, 2023 by The Stationmaster

[keefer]

18 minutes ago, Rugd1022 said:

 

Still a mix of semaphores and colour lights semaphore Keefer - here's a (very) quick sketch of the route with Acton Wells on the left and Dudding Hill on the right...

 

 

 

There is still plenty of traffic using as it's a vital north to south connection in that part of London.

 

 

 

Cheers for that Nidge.

Just looked at the CartoMetro map and see the northbound connection at NJ to Neasden (Met/Chiltern) but the main connection at DH is to the MML not the WCML as I mistakenly remembered. (Down WCML via ACW, Up via AWJ & NSW sidings)

Edited December 8, 2023 by keefer

[HillsideDepot]

Penzance is a location which is heavily influencing my big layout project, still at the planning stage, so I am following along here with great interest. 

 

One of the websites which has yielded much information is the Cornwall Railway Society and the galleries therein (I'm also drawing on elements of Newquay and Barnstaple, both of which they cover) and they have a photo of the real signal in question from July 1974, just after the layout was resignalled.  
http://www.cornwallrailwaysociety.org.uk/uploads/7/6/8/3/7683812/_1767584_orig.jpg 

 

Another useful site is The Eric Curnow Collection, and he has the signalling notice posted. Arguably 1974 is mid-70's rather than early-70s, but these sources may be of interest.

Edited December 8, 2023 by HillsideDepot
To add photo

[beast66606]

9 hours ago, bécasse said:

The crucial point is that they can only be used where speeds are low. IIRC (and the rule hasn't changed) Theatre Light indicators in c/l areas require an imposed speed limit of 40 mph or less and the limit for mechanical indicators was probably even less - 25 mph?

 

Only for the theatre indicated route = PN249, acting as up main home for Lancaster, has a theatre but shows a straight Y/YY/G for the up fast with a line speed of 75mph

[BluenGreyAnorak]

33 minutes ago, HillsideDepot said:

One of the websites which has yielded much information is the Cornwall Railway Society and the galleries therein (I'm also drawing on elements of Newquay and Barnstaple, both of which they cover) and they have a photo of the real signal in question from July 1974, just after the layout was resignalled.  

 

Another useful site is The Eric Curnow Collection, and he has the signalling notice posted. Arguably 1974 is mid-70's rather than early-70s, but these sources may be of interest.

 

That is a great find, thank you. So that signal clearly has a route indicator of some description. Does anybody know what form it took or what it displayed? 

 

[beast66606]

On 06/12/2023 at 18:05, Jeremy Cumberland said:

Not just station limits. For the distant to be cleared, Line Clear is needed for the section in advance (if there is one). Terminal stations don't have a section in advance, of course, and until about 1975 or 76, the distant could be cleared if the line was clear to the buffer stops.

 

 

For a distant to be cleared all the stop signals controlled from the box need to be cleared (and sometimes other things like a face disc showing it's ok to be cleared) - line clear is part of block working, not interlocking, and until the mid 1970s some boxes still worked passenger lines without requiring a line clear release on the section signal.

 

Generally semaphore distants would not be cleared for a terminal station, Birkenhead Woodside had a working distant up to the buffer stop but was unusual in this.

 

Colour light areas were different as the signals reading to the final stop signal were (normally) repeaters rather than distants so could show a green if the next signal was showing proceed, only the last stop signal was peculiar in that it used to show a green onto a red (the buffer stop) - this was "corrected" after Moorgate. I can remember hanging out of train windows (tut tut) while running into Lime Street with greens all the way down the cutting, running into platform 9 on greens could be "lively"

[beast66606]

3 minutes ago, BluenGreyAnorak said:

 

That is a great find, thank you. So that signal clearly has a route indicator of some description. Does anybody know what form it took or what it displayed? 

 

 

Looks like a stencil, it's made up of blocks, each block would show a single character - probably 1,2,3, etc and possibly S for siding or G for goods - a copy of the signal box diagram for the era will show what it's capable of showing

[beast66606]

1 minute ago, beast66606 said:

 

Looks like a stencil, it's made up of blocks, each block would show a single character - probably 1,2,3, etc and possibly S for siding or G for goods - a copy of the signal box diagram for the era will show what it's capable of showing

 

et Viola ..

 

https://www.gwra.co.uk/auctions/british-railways-western-region-signal-box-diagram-2023mar-0250.html

 

1,2,3 and 4 it can show

[BluenGreyAnorak]

Ah, thanks. I realise now that that detail was included in the signalling notice that HillsideDepot linked to above.

[The Pilotman]

49 minutes ago, beast66606 said:

et Viola ..

[Pacific231G]

13 hours ago, bécasse said:

The crucial point is that they can only be used where speeds are low. IIRC (and the rule hasn't changed) Theatre Light indicators in c/l areas require an imposed speed limit of 40 mph or less and the limit for mechanical indicators was probably even less - 25 mph?

They could in principle show a blank display when set for a fast route but I  don't know if the GWR/WR's mechanical "cash register" or "clack box" indicators ever did. I suspect that they had to offer a posiive indication of direction past a cleared signal as, unlike a junction signal, they'd give no indication of direction, so wouldn't fail safe . All of those I've found in SBDs so far had a lever for each indicator that also clears the stop signal but no lever indicated to clear a stop signal without a directoopn indication.

I thought I might find something at Oxford where a gantry just off the down end of the platforms had no less than five of them. howeve, those on the down lines are associated with a junction signal and the remaining three are for reverse down working on the two up lines  and the bay. none of which would have been a fast movement. 

I was though wrong about there being no fast movements through Oxford, I've just seen a photo of a football special passing through the station on the down middle road.

I have also found, in a very grainy corner of a photo, an example of how they were lettered

I can't make out what the two smaller letters  to the right of UP M are.

[Michael Hodgson]

3 hours ago, The Pilotman said:

 

It's a big fiddle.

Edited December 9, 2023 by Michael Hodgson

[keefer]

7 hours ago, Pacific231G said:

I can't make out what the two smaller letters  to the right of UP M are.

Looks to me like OR but I don't know enough about the lines/locations to know what it could be referring to.

[Pacific231G]

3 hours ago, keefer said:

Looks to me like OR but I don't know enough about the lines/locations to know what it could be referring to.

That's how they look to me but " UP M OR  "didn't make any sense to me so I wasn't sure they really were an O and R . The signal was at Banbury until very late- about the late 1980s apparently.

[Jeremy Cumberland]

1 hour ago, Pacific231G said:

That's how they look to me but " UP M OR  "didn't make any sense to me so I wasn't sure they really were an O and R . The signal was at Banbury until very late- about the late 1980s apparently.

The exit from the engine shed at Banbury had a theatre box, with the routes described in the 1958 SRS diagram as "Spur", "Down Main" and "Up Main or Up Sidings". Is this the signal in your photograph?

[The Stationmaster]

15 hours ago, BluenGreyAnorak said:

 

That is a great find, thank you. So that signal clearly has a route indicator of some description. Does anybody know what form it took or what it displayed? 

 

It's a standard WR stencil indicator with the individual boxes for each route stacked vertically and a common shade fitted around them

[The Stationmaster]

12 hours ago, Pacific231G said:

They could in principle show a blank display when set for a fast route but I  don't know if the GWR/WR's mechanical "cash register" or "clack box" indicators ever did. I suspect that they had to offer a posiive indication of direction past a cleared signal as, unlike a junction signal, they'd give no indication of direction, so wouldn't fail safe . All of those I've found in SBDs so far had a lever for each indicator that also clears the stop signal but no lever indicated to clear a stop signal without a directoopn indication.

I thought I might find something at Oxford where a gantry just off the down end of the platforms had no less than five of them. howeve, those on the down lines are associated with a junction signal and the remaining three are for reverse down working on the two up lines  and the bay. none of which would have been a fast movement. 

I was though wrong about there being no fast movements through Oxford, I've just seen a photo of a football special passing through the station on the down middle road.

I have also found, in a very grainy corner of a photo, an example of how they were lettered

I can't make out what the two smaller letters  to the right of UP M are.

Not quite as you describe in ternms of what the signals were.  in the two Down lkines there was a running signal witha 4 ft arm plus a splitting signal with a 3 ft  and teh splitting signals read to a variiety of low speed routes.  The ones applying to the Up lines - at the right handd part of the gantry had basically replaced Backing Signals which also had indicators to read to various routes.

 

The Backing Signals all had route indicators and the one for the Up Main had read to 4 routes, the other two seem only have read to a couple of routes.   The splitting arms on teh Down Lines had originally been 'stacked' 3ft arm signals and only read to two routes but presumably the indicators were used to improve sighting of the running signals.  according to one source the gantry was erected in late 1959.

 

The signal in your photo is showinga route to UP Main - using small letters for part of a word was a thing Reading sometimes did.  

Here's a photo of mine which includes part of the Oxford gantry - a bit washws out as my intetest was the Bulleid pacific.  I have colour slides I took of the gantry in 1973 before it was replaced under Oxford MAS scheme.

 

 

 

Edited December 9, 2023 by The Stationmaster

[The Stationmaster]

16 hours ago, beast66606 said:

 

Only for the theatre indicated route = PN249, acting as up main home for Lancaster, has a theatre but shows a straight Y/YY/G for the up fast with a line speed of 75mph

There was one like that on the D wn Relief at Reading (R132??) and it gave no indication of route for a route set to the Down Relief but an indication for all the other routes.

[Mike_Walker]

53 minutes ago, The Stationmaster said:

There was one like that on the D wn Relief at Reading (R132??) and it gave no indication of route for a route set to the Down Relief but an indication for all the other routes.

Quite a few like that have been installed in recent times.  Not sure I approve...

[Michael Hodgson]

13 hours ago, Pacific231G said:

They could in principle show a blank display when set for a fast route but I  don't know if the GWR/WR's mechanical "cash register" or "clack box" indicators ever did. I suspect that they had to offer a posiive indication of direction past a cleared signal as, unlike a junction signal, they'd give no indication of direction, so wouldn't fail safe . All of those I've found in SBDs so far had a lever for each indicator that also clears the stop signal but no lever indicated to clear a stop signal without a directoopn indication.

In principle I think they could have could have done it if they wanted to, as the interlocking would look after it.  The separate levers for each route would be interlocked with points appropriate to the relevant route, so would be fail safe as you suggest.  An additional lever for the higher speed main route would merely need to operate  the main arm directly without needing any indication to lift, and as it too would of course be locked against diverging points it could only clear when that route was set.  So should a signalman erroneously attempt to clear the main signal instead of that for the diverging route he had set, he would find the main lever locked and have to pull the appropriate lever.  The distant would be released by the main signal for the high speed route, but not for the diverging routes, so if divergence was set, the trains should approach at reduced speed.

[BluenGreyAnorak]

2 hours ago, The Stationmaster said:

It's a standard WR stencil indicator with the individual boxes for each route stacked vertically and a common shade fitted around them

 

Thank you, Mike. Any idea what the each indicator might say? It seems rather large to just be the platform numbers, so might they have each read 'Platform X' or perhaps abbreviated to 'Plat X'?

[TheSignalEngineer]

20 hours ago, Rugd1022 said:

 

Still a mix of semaphores and colour lights semaphore Keefer - here's a (very) quick sketch of the route with Acton Wells on the left and Dudding Hill on the right...

 

 

 

There is still plenty of traffic using as it's a vital north to south connection in that part of London.

 

 

 

We put in those colour lights at Acton Canal Wharf when the Acton Wells panel was done for making two roads through South West Sidings into passenger lines. 

[Rugd1022]

33 minutes ago, TheSignalEngineer said:

We put in those colour lights at Acton Canal Wharf when the Acton Wells panel was done for making two roads through South West Sidings into passenger lines. 

 

I remember going into SW Sidings in the old days and coming to a stand at the stop board at the Acton Wells end, then having to walk all the way down to the other end to wake the shunter up who was fast akip in Acton Lane 'box!

 

About a year ago I was sat at Canal Wharf waiting to get across the junction at Wells when a Richmond bound unit failed right on the points, I sat there for two hours while it all got sorted. With five double track lines converging it's a very busy bottleneck at times.

[TheSignalEngineer]

A few memories of that area. When we took the panel up to Acton Wells I had finished my stuff by about 5am. Started to drive back north up the M1 but could hardly see the road in front of me through the fog so pulled off at the services and had a sleep for a couple of hours. 

The gang doing the base for the new colour light distant at Acton Canal borrowed a troley. Unfortunately the brake was faulty and they lost control of it. Fortunately it was derailed by the traps at Acton Wells and ended up about six feet from the main line.

Later during the commissioning of the passenger lines I went into South West Sidings shunt frame to see it signed out for the last time and to set the gang to work on recovery. The painters turned up to paint the box, so we informed them that we could demolish it quicker than they could paint it. The foreman said they would go to the next job on the sheet, Acton Lane. "Too late" said the the S&T inspector, "It's already been signed out."