SR letter and number headcodes

contrex · 2 Aug 2020

In this article https://sremg.org.uk/RlyMag/GuildfordViaCobham.pdf there is a picture captioned "Train from London Bridge via Bookham joining the Cobham Line at Effingham Junction in April, 1955". The train has a 1925 type SUB leading, with the headcode L with two dots above (London Bridge - Guildford via Mitcham Junc and Epsom). The trailing unit seems to be a 1946 type "Queen Mary" 4-SUB. When the train made its return journey, would the post-war unit have shown the letter headcode or its numerical equivalent (03)?

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DerekC · 2 Aug 2020

I have no idea, but thanks for the link to the interesting article. Hopefully somebody else can answer your question.

Taunton · 2 Aug 2020

I'm pretty sure it would have shown the numbers. There was only one box of stencils in the cab, and at the transition there would have been no desire to have two of them.

With the numbers there were only 10 stencil plates, 0-9, which is why for 2-digit codes there were no double numbers like 44. It still gave sufficient combinations. I don't know how many old letter plates there might have been, but they did by the end have to resort to workarounds like upside-down plates to get as many different codes as needed.

contrex · 2 Aug 2020

i used to occasionally see SUBs with, in place of stencils, numbers crudely daubed in black paint on the white opal glass behind which light bulbs shone at night. I supposed the units were needed to go somewhere urgently and the needed stencils were absent.

big all · 2 Aug 2020

contrex said:
i used to occasionally see SUBs with, in place of stencils, numbers crudely daubed in black paint on the white opal glass behind which light bulbs shone at night. I supposed the units were needed to go somewhere urgently and the needed stencils were absent.

that would be buffer greace

you couldnt paint anything on as units jumped to different numbered service often several times a day ??
when we has a sub on the south london[vic to london bridge] on the odd occasion you would just carry the frame with 22 in it from end to end .

ianhr · 3 Aug 2020

If the leading unit was a Bulleid all steel 6 aside/wide bodied 4 SUB it would have carried a numerical stencil headcode. These were later replaced by roller blinds.

The letter stencil headcodes were introduced by the LSWR and carried by all pre-war suburban stock (the 3 SUBs) and also the stock rebuilt from LSWR 3E units and the augmented 4 SUBs formed from LSWR, LBSCR and SECR stock with Bulleid trailers.

However the 2 NOLs, pre-war conversions from LSWR steam stock with a strong resemblance to 3 SUBs, only ever carried numerical stencils as they were intended for outer suburban and semi fast services but soon became common user and often appeared on inner suburban routes, frequently in multiple with a 4 SUB.

When the first Bulleid 6 aside 4 SUBs, 4101-10, the 'Shebas', appeared in in 1941 they carried numerical stencils, as did all subsequent all steel suburban stock, 4 SUBs and 4 EPBs.

The last letter stencils disappeared in 1962 with the withdrawal of the last of the 1925 stock. The last LBSCR units were withdrawn a year or so earlier.

ianhr · 3 Aug 2020

Sorry, correction! 4 EPBs carried numerical roller blinds from the beginning, never stencils!......and of course they could not be coupled in multiple with 4 SUBs or 1935 stock.

contrex · 3 Aug 2020

There were a few "odd" postwar SUBs with roller blind headcodes and only part steel bodies (canvas roofs) that looked distinctly odd. They sounded odd too, with BTH motors I think. I don't mean the 4101 - 4110 "Shebas". They had the 1946 type flat front like standard 4-SUBs and tin HALs. I'm trying to find the unit numbers at the moment. They were the first to be withdrawn in the later 1960s.

ianhr · 3 Aug 2020

contrex said:
There were a few "odd" postwar SUBs with roller blind headcodes and only part steel bodies (canvas roofs) that looked distinctly odd. They sounded odd too, with BTH motors I think. I don't mean the 4101 - 4110 "Shebas". They had the 1946 type flat front like standard 4-SUBs and tin HALs. I'm trying to find the unit numbers at the moment. They were the first to be withdrawn in the later 1960s.

I think I know the sets you mean. I believe the numbers followed on directly from the Shebas, i.e. 4111......etc. Yes they were not strictly all steel as they had canvas roofs with a rain strip at the normal level along the tops of the doors?....which made them recognisably different from the later, more typically Bulleid units with the high rain strip, which incidentally enabled heavy rain to pour down over an open door (not one of Bulleid's better ideas!). I think some were all compartment like the Shebas and some had semi saloon driving motor brake coaches like later 2-EPBs and 2-HAPs. I understand that it took Eastleigh works some years to develop jigs for the assembly of the all steel Bulleid stock, which is why the wood and canvas roofs were perpetuated since the fabrication of the steel roof proved more difficult than sides and ends, and was not worthwhile until orders for long production runs could be guaranteed. The rain strip position of the Bulleid 4-EPBs evolved in the opposite direction to the SUBs. The first series had the high roof join and later units the more conventional position, presumably by then Bulleid was well out of the way! They did not revert to canvas roofs though!

contrex · 3 Aug 2020

4111 looks all steel to me...

https://www.gettyimages.ca/detail/n...-unit-4-sub-carriage-set-news-photo/102725609

Deepgreen · 3 Aug 2020

contrex said:
4111 looks all steel to me...

https://www.gettyimages.ca/detail/n...-unit-4-sub-carriage-set-news-photo/102725609

4111 was the first of the flat-front design. It also included a composite trailer, which never ran as such in service. These vehicles were easily recognisable by their much wider compartments and surprisingly many survived in SUBs and EPBs (replacing damaged vehicles) into the 1980s.

Deepgreen · 3 Aug 2020

The first photo of the article shows the Oxshott bridge from which a cement mixer lorry fell several years ago, landing on the roof of a class 455 which, unluckily, was departing towards London at that moment.

big all · 3 Aug 2020

looking at "southern electric album " book and on page 59 says" canvas roofs perpetuated even on 4101-10 ??
with 2 pictures

big all · 3 Aug 2020

it also says 4111 was the first all steel unit and set the standard for all subsequent units

ianhr · 3 Aug 2020

contrex said:
4111 looks all steel to me...

https://www.gettyimages.ca/detail/n...-unit-4-sub-carriage-set-news-photo/102725609

Yes, I agree it does. It also has the rather odd semi circular scoop type vents over the door droplights rather than the more usual lozenge shaped toplights.

The early history of the Bulleid 4-SUBs is very complicated but described in great detail in David Brown's "Southern Electric" Volume One. It looks as though sets 4355-4377 were decidedly non standard. 4111 onwards were all steel. Most of the augmentation trailers had the wood and canvas roofs and externally resembled the Shebas. With reformations of the sets and eventual scrapping of the LSWR and SECR stock some of these may have ended up with all steel MThBs. Your picture of the train coming off the Bookham line looks like one of the LSWR 4 SUBs which would have been very near the end of it's life by 1955, although 2 vehicles, a MThB and a trailer survived until c1960 formed into a hybrid set with 2 LBSCR vehicles in the 45xx series, and I remember this one well.

I'm still trying to identify the Bulleid 4 SUBs with the cantrails but it now seems that they must have been all steel.

ianhr · 3 Aug 2020

Deepgreen said:
4111 was the first of the flat-front design. It also included a composite trailer, which never ran as such in service. These vehicles were easily recognisable by their much wider compartments and surprisingly many survived in SUBs and EPBs (replacing damaged vehicles) into the 1980s.

Yes, luxurious. You would always go for one of these. What a contrast to the Shebas which were probably the most uncomfortable trains ever, although 4101 had a pseudo composite trailer.
I believe at some point all the remaining compartment trailers were withdrawn and replaced by saloons to deter antisocial behaviour.

Taunton · 4 Aug 2020

I saw a list of what was the difference between the SUB and EPB, and although the basic body and frame were the same (a number of SUB cars were converted to EPB and remarshalled), the systems differences were substantial. Not just the brakes but everything.

I was quite surprised in using a SUB from Waterloo in what must have been 1983 to find the guard dispatching it at each station by holding a green flag, and the driver looking back. Having known dmus since they first came along, and Wirral electrics from our time there, older than SUBs and which would have been getting on for 50 years old by that time were they not long replaced, I really couldn't believe the SUBs didn't have starting bells/buzzers; they had no low voltage system.

Regarding the timber/canvas roofs, if the SR was anything like Swindon, as BR moved into all-steel vehicles it was a real issue what to do with the substantial force of bodybuilding carpenters at the main works; I believe there was a longstanding issue that those working with steel on welding/riveting were a different union (boilermakers?) to those working with timber, and something had to be found for the existing workforce to contribute; of course, the carpenters continued to work on the interiors.

big all · 4 Aug 2020

Taunton said:
I saw a list of what was the difference between the SUB and EPB, and although the basic body and frame were the same (a number of SUB cars were converted to EPB and remarshalled), the systems differences were substantial. Not just the brakes but everything.

I was quite surprised in using a SUB from Waterloo in what must have been 1983 to find the guard dispatching it at each station by holding a green flag, and the driver looking back. Having known dmus since they first came along, and Wirral electrics from our time there, older than SUBs and which would have been getting on for 50 years old by that time were they not long replaced, I really couldn't believe the SUBs didn't have starting bells/buzzers; they had no low voltage system.

Regarding the timber/canvas roofs, if the SR was anything like Swindon, as BR moved into all-steel vehicles it was a real issue what to do with the substantial force of bodybuilding carpenters at the main works; I believe there was a longstanding issue that those working with steel on welding/riveting were a different union (boilermakers?) to those working with timber, and something had to be found for the existing workforce to contribute; of course, the carpenters continued to work on the interiors.

subs did have control voltage via a potentiometer a big resistance that reduced line voltage to 70v for lights and control voltage for the 8 wire control jumper the lighting wire was seperate but could act as an unofficial "starting buzzer" as the relays where in the cab so lights off and lights on would give a "click click " like a ding ding
if you look back at my earlier posts it covers the all steel canvice situation ??

big all · 4 Aug 2020

just to clarify its 70v control voltage on lights at the actual circuits where between 4 and ten bulbs in series giving 240v in cabs and 70v in gaurds vans and passenger accommodation

30907 · 4 Aug 2020

Taunton said:
I was quite surprised in using a SUB from Waterloo in what must have been 1983 to find the guard dispatching it at each station by holding a green flag, and the driver looking back. Having known dmus since they first came along, and Wirral electrics from our time there, older than SUBs and which would have been getting on for 50 years old by that time were they not long replaced, I really couldn't believe the SUBs didn't have starting bells/buzzers; they had no low voltage system.

Even if the post-war Subs had had buzzers, none of the earlier stock had, so they would have been of limited use. The changeover to EP stock would have been the obvious moment to change.

I wonder, did the desire for buzzers lead to the low voltage supply or the other way around?

Journeyman · 5 Aug 2020

Yeah, the post-war SUBs were designed to be compatible with all suburban and semi-fast EMUs built since the initial batch of LSWR electrics in 1914! This is why the Southern was so slow to introduce electro-pneumatic brakes, starting buzzers and even really simple stuff like electric tail lights. The SUBs had no low-voltage or battery supplies, and pretty much everything worked off line voltage. By the time they were built, their electrical systems were shockingly crude - if the traction supply was lost, the train was instantly plunged into darkness. Although the EPBs looked similar and had a lot of interchangeable parts, like motors and compressors, they were a lot more sophisticated.

ianhr · 5 Aug 2020

Journeyman said:
Yeah, the post-war SUBs were designed to be compatible with all suburban and semi-fast EMUs built since the initial batch of LSWR electrics in 1914! This is why the Southern was so slow to introduce electro-pneumatic brakes, starting buzzers and even really simple stuff like electric tail lights. The SUBs had no low-voltage or battery supplies, and pretty much everything worked off line voltage. By the time they were built, their electrical systems were shockingly crude - if the traction supply was lost, the train was instantly plunged into darkness. Although the EPBs looked similar and had a lot of interchangeable parts, like motors and compressors, they were a lot more sophisticated.

Yes that is my understanding. The first LSWR 3-E units were even cruder. The full line voltage went through the control stand and there were uninsulated conductors in the cabs and switchgear compartment (which was above floor between the motorman and guard's van)! I'm not sure if it is on record whether anyone got a 600V shock, or what the SR did about it. The lighting circuits were energised from tap changers and wired in series and if someone unscrewed a bulb the entire car and possibly the entire unit went dark. There was also a 600V bus line running along the roofs of wooden bodied stock. The last were not withdrawn from traffic until c1940. Does anyone know if the SR carried out safety modifications before that?

contrex · 5 Aug 2020

I once saw a TV prog about Sarah Siddons (the Met loco, not the actress) Slightly later (1922-23). They found a retired driver who mentioned the uncovered knife switches on the back wall of the cab just under the roof. You had to be careful, he said, to only touch the wooden handles, or you'd get a "jolt". He said how he must have touched live metal once because he came to on the floor of the cab amidst the smell of burning hair. Also in Youtube videos of the interior of the loco body you can see, on the switchgear a kind of orifice with a notice in old LT script saying "DO NOT STAND IN FRONT OF THIS ARC CHUTE". In the videos of the loco being driven on Met railtours, the drivers wear these substantial looking gloves. I always thought they were just because the controller hurts their hands if held down for long periods, but maybe there is another reason.

contrex · 5 Aug 2020

" There was also a 600V bus line running along the roofs of wooden bodied stock. " Barnes Bridge comes to mind. Also the Paris Metro and a nasty fire on LT with Standard stock.

Taunton · 6 Aug 2020

contrex said:
I once saw a TV prog about Sarah Siddons (the Met loco, not the actress) Slightly later (1922-23). They found a retired driver who mentioned the uncovered knife switches on the back wall of the cab just under the roof. You had to be careful, he said, to only touch the wooden handles, or you'd get a "jolt".

Some original electric locos were completely open inside, you just walked from cab to cab past the open components.

Bear in mind that drivers came from steam locos, where they generally managed not to put their head in the fire or fall out of the quite unguarded footplate sides. Stories of going up the side of the loco at speed to oil up, or even on double headers clambering across to the other loco, are not unknown either. Exposed loco elements would be nothing.

contrex · 6 Aug 2020

Taunton said:
drivers came from steam locos, where they generally managed not to put their head in the fire

I take your point, but I can't help thinking that electricity brought a new type of hazard. You can see a fire, and momentary fingertip contact with the firebox door won't knock you out cold, seriously injure you, or kill you. I think to some extent the wider electrical industry grew up in those decades too.

ianhr · 7 Aug 2020

contrex said:
I think to some extent the wider electrical industry grew up in those decades too.

We are wandering a long way off the original topic of SR headcodes but this is interesting and maybe worthy of a new thread.

Yes, at that time cWW1 and the 1920s there were no flexible plastics and the usual insulating materials were waxed paper, rubber, various fabrics and wood. I am not sure of the exact conductivity of wet wood but would not in the light of modern understanding want to risk my life to it. Until quite recently if a failed train on the Southern needed to be isolated from the traction supply the crew had to "paddle up" by inserting wooden paddles (which were stored in the cab or guard's van) between the conductor rail and the shoes.

contrex · 7 Aug 2020

Have they stopped paddling up?

This person in 2009 saw paddles in a Desiro cab

Wooden paddles in Desiro cab

Whilst waiting at New Street for my train earlier, I had a nose through the cab window of a Desiro and noticed what I could only describe as two large wooden paddles (like wooden rowing boat oars basically) attatched to the inside of the corridor connection. Any idea what these are for...

www.railforums.co.uk

ianhr · 7 Aug 2020

contrex said:
Have they stopped paddling up?

This person in 2009 saw paddles in a Desiro cab

Wooden paddles in Desiro cab

Whilst waiting at New Street for my train earlier, I had a nose through the cab window of a Desiro and noticed what I could only describe as two large wooden paddles (like wooden rowing boat oars basically) attatched to the inside of the corridor connection. Any idea what these are for...

www.railforums.co.uk

Well I think the technique is well known to a lot of Southern train crews. I would have thought the task became a lot more difficult when they changed from the cast iron 'gravity' shoes, which were held in contact with the conductor rail by their own weight, to the spring loaded de-icing shoes. I don't recall the EPB stock, or anything later, ever carrying gravity shoes, although the prototypes may have done, and I think the all steel SUBs were eventually fitted with the new type (1970s-80s ?). The 1935 stock had the original type of shoes until the end (early 1970s). You could always tell because the gravity shoes which were not in contact with the conductor rail used to rattle, particularly over junctions.

Taunton · 8 Aug 2020

Always seemed a bit of a lost opportunity that the post-war SUBs were not converted to EPB, these following directly after their construction, and the SUBs went for major works overhauls for the next 30 years. It would have made for a nice fully compatible suburban fleet for a long while.

SR letter and number headcodes

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