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White disks on the front of steam locomotives

Discussion in 'Steam Traction' started by charterplan, Nov 3, 2015.

  1. charterplan

    charterplan Member

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    I have always been wondering why they have these disks on the front of the locos,as they do look silly, but know they are there for a reason but what?
     
  2. Spamcan81

    Spamcan81 Nat Pres stalwart

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    Why do SR/BR(S)/GER/BR(GE) route indicator discs look silly?
     
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  3. flying scotsman123

    flying scotsman123 Resident of Nat Pres

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    They were used by the southern, called route indicator discs, and they indicated the route. :) who to though I don't know, I wouldn't have thought the average commuter would memorise route indicators? I've never thought there's been anything aesthetically wrong with them.
     
  4. Charles Parry

    Charles Parry Member

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    The various routes codes for Southern can be found here: http://www.semgonline.com/headcodes/sheadcodes.html

    Head lamps are used to show what sort of train it is (express, parcels, unfitted goods etc), these discs instead show what route the train is taking.
     
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  5. LMS2968

    LMS2968 Part of the furniture

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    Signalmen?
     
  6. Martin Perry

    Martin Perry Nat Pres stalwart Staff Member Moderator Friend

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    + Station staff.
     
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  7. flaman

    flaman Well-Known Member

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    They were also used on the Great Eastern and their use continued well into BR days. The GE system involved discs coloured white on one side and purple surrounded by a white ring on the reverse. The use of these two indications in the various permutations possible with the four head-end lamp brackets, permitted a large number of different routes to be indicated to signalmen, essential particularly for the operation of the "Jazz" services out of Liverpool Street, which when introduced in the 1920s were the world's most intensive steam-worked commuter service. Incidentally, the discs were only used in daylight, head lamps, which, on the GE section had an additional purple indication, being used at night.
    In later years, the use of the discs for route indicating purposes became restricted to the London area, but the discs continued to be used throughout the GE area for the standard codes indicating the type of train. There is plenty of photographic evidence of "Britannias", B1s, Cl.40 and 31 diesels (the earlier examples of which were equipped with permanent folding discs) etc., working with headcode discs into the '60s.
     
  8. Nick Gough

    Nick Gough Well-Known Member

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    Didn't the GER, Southern, etc., put headcodes on their trains to assist book authors in writing appropriate captions for the photos many years later? :)
     
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  9. Wenlock

    Wenlock Well-Known Member Friend

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    In daylight they were also easier to see than a (possibly grubby) headlamp. The SR/BR(S) system used 6 brackets to give a great variety of route indication.
     
  10. flaman

    flaman Well-Known Member

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    I suspect that's the reason for their original introduction. As I'm sure that those members involved with the sharp end of loco operation will know, it is very difficult to keep a headlamp clean and even a white painted one quickly becomes invisible in daylight, even in a present-day preservation situation. Now consider the London area prior to the 1960s, with, at best, a perpetual smoke haze summer and winter and the reason for discs becomes clear (excuse the pun:))

    The question of the Southern discs intrigues me. Not only did they fit an additional lamp bracket either side of the smokebox, they, or the Brighton at any rate, also used a variety of symbols on the discs. Why? Their operation was no larger than the GE's, so was it that much more complex? I'm sure somebody must know!
     
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  11. Martin Perry

    Martin Perry Nat Pres stalwart Staff Member Moderator Friend

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    Was it because the LBSCR had more junctions or shared lines than the GE? Clapham must have been quite an exciting challenge for signalmen in those days.
     
  12. S.A.C. Martin

    S.A.C. Martin Part of the furniture

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    One of the anecdotes I have enjoyed writing about concerns the experiments Edward Thompson took with fixed discs on his Pacifics and one of his B1s during the war. It was pointed out to him on the Pacifics the top folding white disc might foul the loading gauge. Once that was sorted, there were problems with sending the locos out on the Eastern section - as the rulebook didn't cover the use of discs outside of the GE section! The idea was quietly dropped towards the end of his tenure, albeit 4470 Great Northern held onto hers for a time.

    His efforts with the folding route/train indicator discs pre-dated the early diesels with folding route indicator discs by some way. Of course they along with the four digit head code panels would become redundant pretty quickly too but it shows that the idea was sound if not carried out in the best way. As with a number of Thompson's ideas perhaps but I'll let you decide that for that yourselves.
     
  13. Jamessquared

    Jamessquared Nat Pres stalwart

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    The system simplified over time, which suggests to me that it was maybe over-specified during the middle Victorian period and then simplified in the light of operational experience.

    Even so, there was a plethora of different routes that all needed describing, hence the use of six discs. The Brighton also tended to have two codes for each route, for "ordinary" and "special" trains, the specials presumably getting priority at junctions. At night, the white discs were replaced with white lights and the crosses with green lights. In the earlier years there were also discs with double diamonds during the day, and purple lights at night; and then to further complicate things, it's not unknown to find pictures of engines carrying discs and lamps simultaneously.

    Another complication must have been trains working to "foreign" stations, particularly in London. Presumably there were provisions in the rule book to change the head code at the first available opportunity? I wonder what foreign engines (e.g. GNR etc) working on to the LSWR / LBSCR / SECR did, given that they may not have had sufficient lamp irons to show a proper code?

    Scope for an interesting research project for someone with access to the necessary rule books!

    Tom
     
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  14. Bean-counter

    Bean-counter Part of the furniture

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    Some of the Footplate Crews got hold of some Southern Region discs and the appropriate guide to what they meant a good few years back on the NYMR - presumably this started the year we had 34072 and 34027 (and yes, somebody managed to oil up the wrong one at least once!) and they kept appearing once we had 34101. Probably getting dug out and polished ready for 34101's return, hopefully in 2016!

    Certainly, the signalmen got to know the codes - I think a brief extract is still on the notice board in Levisham Signal Box. "Waterloo to Portsmouth Habour" was a favourite, I seem to recall!

    Steven
     
  15. Jamessquared

    Jamessquared Nat Pres stalwart

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    Presumably that is Waterloo to Portsmouth Harbour via Petersfield, and not Waterloo to Portsmouth Harbour via York, Pickering and all stations north? ;)

    Tom
     
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  16. Bean-counter

    Bean-counter Part of the furniture

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    I couldn't remember the via! - is it a code that doesn't involve reaching to the top brackets at all? :)

    There also was a Southern route (train hauled by 34101 Hartland from Ashfordly to Crewe once shown on Heartbeat, although Crewe had gained some stone built station buildings that looked as though they were originally designed by G T Andrews!

    Steven
     
  17. Spamcan81

    Spamcan81 Nat Pres stalwart

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    As an aside, in an early episode of The Royal, 34081 in malachite was seen working a train through Ashfordly. Quite a long trip for a Ramsgate loco. :)
     
  18. John Petley

    John Petley Part of the furniture

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    It is an interesting study to observe how discs have been used in preservation. The Bluebell tends to use either the LBSC or SR code for the line when an appropriate engine is rostered. Non-SR locos usually run with lamps, although I do have a photo of the North London Tank bearing the "West of England main line" discs! On the Swanage Railway, the single disc (above the buffer beam in the centre) which was the code for trains on the branch in SR/BR(S) days appears to be the norm and once again, 6695, being non-SR, has invariably run with lamps when I have seen it. I haven't quite worked out the Mid Hants' philosophy when it comes to discs. A quick rummage through my photos reveals all sorts of variations. Perhaps someone involved with that line could enlighten me!

    Both on the main line and when SR locos (particularly Bulleid Pacifics) operate on non-SR preserved line, the most common code in my observation is one disc above each buffer. This was the code for, among other things, some inter-regional trains, so about as appropriate as feasible. I must admit, it is always a bonus when a Salisbury- or Bournemouth-bound main line train runs with the correct disc headcode for the line in question, even if, in 2015, it will hardly bother the signalmen if it doesn't.
     
  19. Jamessquared

    Jamessquared Nat Pres stalwart

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    Indeed it is - one over the left buffer and one at left "half height", as viewed facing the engine. Short-a*ses should have no difficulty :) (No. 13 on this page: http://www.semgonline.com/headcodes/sheadcodes/04.html)

    I had it noted on my firing test that I left on my first trip with an incorrect head code. I wouldn't have minded, except I'd put a Waterloo to Bournemouth code on! If I was going to make a mistake, at least it should have been Salisbury, given where I live and the home shed of the engine... The rest of the day we had the regulation Oxted and Brighton via East Grinstead (Low Level) and Lewes code - I wasn't taking chances...

    Tom
     
  20. Wenlock

    Wenlock Well-Known Member Friend

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    I believe the use of routing codes was more prevalent pre-grouping, I seem to recall reading of green headlamps or coloured discs or even a "semaphore" style indicator on the top bracket on one of the Scottish companies locos.

    Yes I think the LBSC may probably have had more London terminals to choose from.
     

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