BR(S) DEMU could they have been developed further.

[Oldddudders]

20 hours ago, 45655 said:

The SR centre buffer and link coupling was a cheap and robust solution where units rarely needed to be split.

And it was a highly reliable solution, indeed. But, trust me, on the rare occasions that it failed - i.e. the chain broke - it did rather mess things up, with jumpers pulled out and a dead short as a result. It happened in Platform 2 at Dartford, where isolation was fairly easily achieved, but it made operations a little difficult until the Slade Green wallahs were able to fix things and get the unit out of the way.. 

[Wickham Green too]

1 hour ago, Tom Burnham said:

... if EPB units had retractable side buffers as on Mark 1 loco hauled corridor carriages.

... yes, they did.🙂

[45655]

1 hour ago, Tom Burnham said:

Indeed there was.  Incidentally the buckeye couplers used within that one batch of suburban units were US MCB couplers rather than the Laycock take on the buckeye coupler used with Pullman gangways (or the buffing plates shaped like the lower part of a Pullman gangway faceplate).  I'll have to look out old photos to see if EPB units had retractable side buffers as on Mark 1 loco hauled corridor carriages.

The fundamental issue with the early SR buckeye (MCB) implementation was that they didn't fit buffing plates, and the buffing forces set up by multiple motor cars with automatic acceleration (very different from a loco hauled train) led to fractures of the cast steel buckeyes.  They didn't make the same mistake with the post-1951 stock.

 

The pre-War express stock was screw coupled throughout, with wide continental style gangways (basically bellows with faceplates clamped together) rather than the British Standard type.

 

Keith

Alton.

[Southernman46]

On 07/07/2023 at 21:53, phil-b259 said:

 

While its relatively easy to replace parts of the Mk1 bodyshell with new material you will get to a point where the underframe itself has lost so much strength due to 'natural wastage' it can no longer perform as designed.

 

and referring this back to the original thread subject - the vast majority of the issues with the Hastings DEMU's in the later decade or so of their lives were to do with underframe corrosion

[DY444]

4 minutes ago, Southernman46 said:

and referring this back to the original thread subject - the vast majority of the issues with the Hastings DEMU's in the later decade or so of their lives were to do with underframe corrosion

 

No doubt made worse by them being based at St. Leonards

[Tom Burnham]

7 hours ago, Wickham Green too said:

... yes, they did.🙂

As here -

 

 

[Oldddudders]

Elmstead Woods with a down Orpington on the slow lines. I once walked through the fast line tunnel, looking for a broken rail on the up fast - there was a track-circuit failure. I hadn't gone very far when I became aware of an up train approaching, albeit at reduced speed, so I rapidly headed for the cess. Evidently the signalmen at London Bridge and Chislehurst had not come to a proper understanding about my presence..... 

[Southernman46]

1 hour ago, Oldddudders said:

Elmstead Woods with a down Orpington on the slow lines. I once walked through the fast line tunnel, looking for a broken rail on the up fast - there was a track-circuit failure. I hadn't gone very far when I became aware of an up train approaching, albeit at reduced speed, so I rapidly headed for the cess. Evidently the signalmen at London Bridge and Chislehurst had not come to a proper understanding about my presence..... 

Yes I remember this incident - the recordings were briefed out and made sobering listening. We had a similar incident in Wells Tunnel with staff attending a TCF. The Up line should have been blocked with staff in the tunnel but a train was sent forward on the Up. The staff had to stand clear on the (as far as they knew) open Down line (there are no refuges) to avoid being run-down. Stewards Enquiry resulted.

[Nearholmer]

I’m sure there are different rules now, but on the underground the practise was to screw down a train at the entry to the tunnel, and for the person walking through to take the motorman’s key in their pocket.

[St Enodoc]

5 hours ago, Southernman46 said:

Yes I remember this incident - the recordings were briefed out and made sobering listening. We had a similar incident in Wells Tunnel with staff attending a TCF. The Up line should have been blocked with staff in the tunnel but a train was sent forward on the Up. The staff had to stand clear on the (as far as they knew) open Down line (there are no refuges) to avoid being run-down. Stewards Enquiry resulted.

My training, which, fortunately, I never had to put into practice, was to lie face down in either the six-foot or the cess (assuming there was room in a tunnel with juice rails).

[phil-b259]

On 08/07/2023 at 22:50, jim.snowdon said:

Something that has now come to haunt the Severn Valley Railway as an operator of ex-GWR stock. HMRI (aka the ORR) have, I believe now required that they are either taken out of use or fitted with proper slam locks.

 

There is however a benefit from this to the SVR as because most visitors don't appreciate how the GWR locks work they go and slam the door with the tounge of the lock sticking out (as you do with most slam doors) which then slams into the coach side damaging the lock and the doorframe.

 

That said its a cost burden the SVR would no doubt prefer not to have.

Edited July 10, 2023 by phil-b259

[Southernman46]

5 hours ago, St Enodoc said:

My training, which, fortunately, I never had to put into practice, was to lie face down in either the six-foot or the cess (assuming there was room in a tunnel with juice rails).

Or flatten yourself as close to the tunnel wall as possible as I once had to do in Swanscombe Tunnel (nasty little tunnel on a 70mph curve) when caught between refuges once .................... the lookout did get the rough edge of my tongue afterwards.

[Wickham Green too]

On 26/06/2023 at 15:02, 25kV said:

Given that control system interoperability existed between (say) 33s, 73s and EMU stock, it's probably not beyond the bounds of possibility that the SR could have made a bi-mode unit work, ...

On the face of it, a bi=mode Hastings Unit : - 

 

.... but just working as straight electric ...... even 73.213 on the back was along for the ride with its shoes up ! : Eden Park, 10/10/09

 

[DY444]

On 02/08/2023 at 16:43, Wickham Green too said:

On the face of it, a bi=mode Hastings Unit : - 

 

.... but just working as straight electric ...... even 73.213 on the back was along for the ride with its shoes up ! : Eden Park, 10/10/09

 

 

Yes because you can't multi a 73 with a Hastings unit so it and the rear ED is just an air braked formation being hauled.

[jim.snowdon]

On 26/06/2023 at 15:02, 25kV said:

Given that control system interoperability existed between (say) 33s, 73s and EMU stock, it's probably not beyond the bounds of possibility that the SR could have made a bi-mode unit work, so it's perhaps that they just didn't need to... 

Now I'm leaping to the 1980s in my head and a bi-mode Class 210/455 design... :)

Could, but probably never needed to. Full compatibility would only have been justified had there been services which had an operational need to combine with electric units for pathing purposes. During the DEMU era, I can't think of any. There were very few services that required diesel traction and ran into the London termini, which is were the available line capacity is tightest.

[Nearholmer]

The Hastings trains did eat pathing space north of Tonbridge, but to my recollection paths weren’t at quite such a premium ‘back in the day’, and north of Croydon everything seemed to go at a fairly sedate pace to allow all the complex interlocking paths to work anyway, so the DEMUs again weren’t a serious impediment, they kept up reasonably well.
 

As for diesel emissions considerations, it seemed to be the case of “the more the merrier” in the London area, with every bus, taxi, lorry, building-site dump-truck, and everything else contributing to the rich atmosphere of partially burned fuel and soot particles.

 

Plus, DEMUs were always seen as a bit of a temporary stopgap until electrification.

 

So, I’d agree: could have, but didn’t feel the need to add the complexity.

 

 

Edited August 4, 2023 by Nearholmer

[St Enodoc]

4 minutes ago, Nearholmer said:

The Hastings trains did eat pathing space north of Tonbridge, but to my recollection paths weren’t at quite such a premium ‘back in the day’, and north of Croydon everything seemed to go at a fairly sedate pace to allow all the complex interlocking paths to work anyway, so the DEMUs again weren’t a serious impediment, they kept up reasonably well.
 

As for diesel emissions considerations, it seemed to be the case of “the more the merrier” in the London area, with every bus, taxi, lorry, building-site dump-truck, and everything else contributing to the rich atmosphere of partially burned fuel and soot particles.

 

Plus, DEMUs were always seen as a bit of a temporary stopgap until electrification.

 

So, I’d agree: could have, but didn’t feel the need to add the complexity.

 

 

Agreed but I think Jim's point was that there was no operational need to combine EMUs and DEMUs on the same train. Certainly not on the Central, although it might have been an option with Hastings and Ashford trains on the London side of Tonbridge. Those services were probably busy enough in their own right to demand separate trains/paths though.

[Nearholmer]

Ah, I see, yes, slightly different question, and I agree: no need to combine.

[The Lurker]

3 hours ago, St Enodoc said:

Agreed but I think Jim's point was that there was no operational need to combine EMUs and DEMUs on the same train. Certainly not on the Central, although it might have been an option with Hastings and Ashford trains on the London side of Tonbridge. Those services were probably busy enough in their own right to demand separate trains/paths though.

They were in the morning rush - viewing the phalanx of commuters on Tonbridge platform as we schoolboys tried to get off is a vivid memory even now 40+  years later. They weren't keen on letting us through even though it slowed them down getting on...!

[Nearholmer]

At Tunbridge Wells Central, they used to line-up in files, knowing exactly where the doors would be, and then all go aboard in strict order, to their personal favourite seats, each armed with a folded newspapers (mostly Telegraph) to beat-off anyone who might buck the queueing system or steal their seat. If people back down the line at Battle or wherever had mucked things up by sitting in the wrong chair, the silent fury was palpable. Some of them carried folding wooden fishing stools for use in case of  extreme delays and congestion too - they usually came out on the way home if there was a hippopotamus on the line at Grove Park, or the like.

[Tom Burnham]

9 hours ago, Nearholmer said:

The Hastings trains did eat pathing space north of Tonbridge...

As I recall in the late 60s the Ashford line semi-fasts had an Orpington stop but the Hastings diesels were non-stop from Waterloo East to Sevenoaks. Presumably as the diesels had slower acceleration on the climb to Knockholt.

[Wickham Green too]

It's the reverse now - Hastings trains stop at Orpington but if I want to head to the Kent coast I have to change at Sevenoaks or Tonbridge ......... though the Journey Planners often suggest back-tracking to St.Pancreas and using HC1* !

 

*High Cost 1

[Mike_Walker]

18 hours ago, Nearholmer said:

At Tunbridge Wells Central, they used to line-up in files, knowing exactly where the doors would be, and then all go aboard in strict order, to their personal favourite seats, each armed with a folded newspapers (mostly Telegraph) to beat-off anyone who might buck the queueing system or steal their seat. If people back down the line at Battle or wherever had mucked things up by sitting in the wrong chair, the silent fury was palpable. Some of them carried folding wooden fishing stools for use in case of  extreme delays and congestion too - they usually came out on the way home if there was a hippopotamus on the line at Grove Park, or the like.

I think you'd find similar on many commuter routes into London; it certainly applied even on my local branch line.  If the unit arrived the "wrong way round", i.e. with the van and first class not where they were expected, confusion and chaos abounded.  As for the Telegraph (and other broad sheets back in the day) it was amazing how many concealed a copy of the Sun!  You could spot that more easily on a open DMU than in compartments.

[Southernman46]

Indeed - spent many a happy hour sat in CEP / VEP corridors on one of these back in the 80's - folded up small enough to go inside a briefcase (pre-backpack days) 👍