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Imaginary Locomotives


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10 hours ago, DenysW said:

As an afterthought, Bulleid might well have decided to out-Ivatt LMS, and pro-actively embrace the incoming diesel era at LNER immediately post-war. After all, Gresley had produced the right express steam for the London-Edinburgh route, and adequate express steam for the Edinburgh-Aberdeen route, so what is left? Better goods steam locomotives - not sexy at all.

Mrs Bulleid might have had a little word or two with her hubby after all Henry the younger was her brother.

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On 10/11/2021 at 10:35, DenysW said:

As an afterthought, Bulleid might well have decided to out-Ivatt LMS, and pro-actively embrace the incoming diesel era at LNER immediately post-war. After all, Gresley had produced the right express steam for the London-Edinburgh route, and adequate express steam for the Edinburgh-Aberdeen route, so what is left? Better goods steam locomotives - not sexy at all.

Really? I'd say that the end-of-steam-era Big Boy and Challenger types were some of the sexiest steam designs anywhere. The South African Garratts were right up there, too. 

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22 minutes ago, Flying Pig said:

Over 400 Thompson B1s were built and the requirement would still be there if Bulleid had the Big Pencil.  What would a Bulleid equivalent look like, with similar wartime constraints on cost and complexity?

He did, and they look exactly like a West Country cos' that is the Bullied B1 equivalent.

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"Really? I'd say that the end-of-steam-era Big Boy and Challenger types were some of the sexiest steam designs anywhere. The South African Garratts were right up there, too. "

 

Let's also not forget the AE class of the Virginian Railway, with the 48" low pressure cylinders. Slow but hugely powerful.

 

However, this thread routinely points out the stranglehold on locomotive power imposed by UK loading gauge, and the US designs are a very long way indeed from fitting into it. I also believe (i.e. it's my own calcs) that the Big Boys required 40 tons/axle permanent way, and the Virginian 30 tons/axle. And that's before thinking about how to fit freight trains that long into our block system, and how they'd cope with our unbraked goods, and with needing 130' turning circles (the Virginian cheated with short tenders because it only had 105' turning circles).

 

So I still don't think that improved UK-relevant goods designs got you a knighthood, and nor, it seems, for example, did fixing the design and maintenance practices that gave hot axle boxes on MR/LMS designs.

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The general philosophy of UK freight locomotives should generally be "how can we move 40 wagons at 35mph more efficiently", rather than "how do we get a 100 wagon train to 35mph". I'm rather surprised turbine & geared locomotives didn't flourish under those conditions, given their efficiency at design speed, although the more variable speeds on a railway and the "good enough" mentality towards 0-6-0's ultimately explain precisely why.

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I believe 25 mph (full) and 50 mph (empty) for mineral traffic may be more representative of LMS in the 1920s/30s, judging by the Garratts.

 

What they all failed to solve (due to a combination of freight rates agreed to avoid ruinous competition, inertia, and lack of capital) was conversion to braked goods to get those speeds up to 40 mph, and get more trains/hr down the congested lines into the conurbations.

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2 hours ago, DenysW said:

So I still don't think that improved UK-relevant goods designs got you a knighthood, and nor, it seems, for example, did fixing the design and maintenance practices that gave hot axle boxes on MR/LMS designs.

 

Though instituting those policies seems to have got Guy Granet one.

 

3 hours ago, john new said:

He did, and they look exactly like a West Country cos' that is the Bullied B1 equivalent.

 

Not really - the B1 was built down to a price as part of Thompson's standardisation campaign (the range of types it was initially intended to represent is listed on lner.info).  Bulleid might not have persued such a wide-ranging standardisation program, but it is unlikely the LNER,would have allowed him to build anything as outré as the West Country in the required numbers.

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8 minutes ago, Flying Pig said:

 

Though instituting those policies seems to have got Guy Granet one.

 

 

Not really - the B1 was built down to a price as part of Thompson's standardisation campaign (the range of types it was initially intended to represent is listed on lner.info).  Bulleid might not have persued such a wide-ranging standardisation program, but it is unlikely the LNER,would have allowed him to build anything as outré as the West Country in the required numbers.

The question asked was what would Bullied have built? I didn’t say the WC/BBs we’re better, just that they were officially a mixed traffic Bullied designed loco’ built for the Southern, i.e. the equivalent to the LNER’s B1, in a comparable time frame. Of the two I fully concur the B1 as a simple standard loco was what the LNER needed, the complex chain drive SR pacific arguably not so, the B1 better met the needs of the LNER. With the benefits of hindsight, and the later rebuilding programme put into place for the SR Pacific’s, it might well have better suited the SRs needs too.

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4 minutes ago, john new said:

The question asked was what would Bullied have built? I didn’t say the WC/BBs we’re better, just that they were officially a mixed traffic Bullied designed loco’ built for the Southern, i.e. the equivalent to the LNER’s B1, in a comparable time frame. Of the two I fully concur the B1 as a simple standard loco was what the LNER needed, the complex chain drive SR pacific arguably not so, the B1 better met the needs of the LNER. With the benefits of hindsight, and the later rebuilding programme put into place for the SR Pacific’s, it might well have better suited the SRs needs too.

 

Isnt that what the Std 5 & 4 did for the Southern?

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1 hour ago, DenysW said:

I believe 25 mph (full) and 50 mph (empty) for mineral traffic may be more representative of LMS in the 1920s/30s, j

In "Chronicles of steam" Cox talks about testing in the 1930s with "the 17mph average running speed of the working timetable" and some experimental runs  at 23mph with a lighter load.

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" "the 17mph average running speed of the working timetable"

 

This is absolutely true for the Garratts on the down (loaded) journey. Sixsmith quotes stops as being made at Brentingly (15 minutes) and Luton for water, and 25 minutes at Wellingborough for general engine requirements. The down running time was 7 hrs 49 minutes for 126.5 miles, but the total time start-to-stop was 10 hrs 24 minutes.

 

Care is thus needed to distinguish between running speeds, and journey-time speeds.

 

50 mph for return (empty) journey is an assertion from Wikipedia and is more likely to be running time than journey time.

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43 minutes ago, John Besley said:

 

Isnt that what the Std 5 & 4 did for the Southern?

Yes, but they were not built as MT engines (the Light pacifics official description) designed under WW2 conditions they came later. People may criticise Thompson’s locomotives but he was a very good production side engineer and saw the need to reduce variety and standardise. Riddles continued for BR what Thompson had also been aiming for namely moving towards a range of standard locomotives - Thompson’s B1 being one of the 21(?) identified types to be built/retained by the LNER going forward.

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On 14/11/2021 at 17:24, tythatguy1312 said:

The general philosophy of UK freight locomotives should generally be "how can we move 40 wagons at 35mph more efficiently", rather than "how do we get a 100 wagon train to 35mph". I'm rather surprised turbine & geared locomotives didn't flourish under those conditions, given their efficiency at design speed, although the more variable speeds on a railway and the "good enough" mentality towards 0-6-0's ultimately explain precisely why.

The question was more "how can we stop 40 wagons going at 25mph in less than 2 miles". A powerful 2-8-0 didn't have much more stopping power on an unfitted goods than an 0-6-0 did. 

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On 14/11/2021 at 19:55, DenysW said:

50 mph for return (empty) journey is an assertion from Wikipedia and is more likely to be running time than journey time.

 

That sounds highly improbable. It's still an unfitted loose coupled train with many wagons having grease axleboxes, whichever direction it's going in. 

 

On 14/11/2021 at 18:46, Flying Pig said:

Though instituting those policies seems to have got Guy Granet one.

 

Indeed; I'd assumed it was for his war work but looking it up I see he got his knighthood in 1911.

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(Sir) Guy Granet was an administrator and a lawyer, not an engineer. Having just exploded my brain by reading the thread about 'what would have made the Midland abandon its small engine policy', he does seem to have been a (very) competent administrator, who introduced coordinated system for goods management that reduced costs. He didn't get the knighthood for designing goods engines, or better matching what was built with what was starting to be needed. I still hold to the cynical opinion that faster passenger locos get knighthoods, and more efficient freight locos don't.

 

I agree with the previous rebuke on this that the company might have a greater need for better goods vehivles, irrespective of sexyness.

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4 hours ago, Compound2632 said:
On 14/11/2021 at 19:55, DenysW said:

 

 

That sounds highly improbable. It's still an unfitted loose coupled train with many wagons having grease axleboxes, whichever direction it's going in. 

 

Two schools of thought here.  The subject under discussion being the running of loose coupled unbraked coal trans and the return empties, the trains being up to 60 wagons long on 'normal' routes and up to 100 wagons on the London runs (Severn Tunnel-Acton, Toton-Cricklewood, Peterborough-Finsbury Park and the like) where special signalling instructions  were used.  In my day on BR, loose coupled class 9 trains were speed restricted to 25mph and in practice rarely ran that fast.

 

But there was also the 'Windcutter/Annesley Runner' method, in which a through road was established over a long distance and, in the interests of keeping the couplings tight, the loco pulled consistently all the time and speed built up, to some surprising figures in the case of the Windcutters, despite the 9' wheelbase wagons, and predicated on the concept of having a long time available to gently slow the train down at the end of the adventure.  This worked well on the Great Central where traffic was light in the 60s and the method was not only possible but arguably the best use of the resouces.  Risky, though...

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Open mind. Sixsmith doesn't quote the return times (and those numbers originate from a Derby report 6 months into the trial of the first three units, thus with new-conditions locos), so that avenue is closed.

 

There was the one-off trial of using an LMS Garrett in the 1930s with a rake of passenger coaches, implying LMS didn't totally rule out using them on heavy stopping services. But it did fail due to a hot axle box and limped only as far as Leicester. So it may come down to whether you believe that the lighter-load/higher-speed (less slow?) combination caused the failure, or whether it was just a random incident of that (relatively) common problem.

 

There also seem to have been several Toton-Cricklewood routes, at least in Leicestershire, and I find it difficult to believe the riskier approach would have been available on all and for all timings.

 

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Back to the imaginary ones ...

 

Would the next development for the Beyer-Garratt (and even the LMS ones once you fix the axleboxes) have been to go the turbine route with fore-and-aft turbines? On 6202 Stanier/LMS seem to have reduced the one-speed-only characteristic of turbines to manageable levels, and a Garratt design gives you the opportunity to re-engineer the exhaust pressure from the turbine to give the same suction into the chimney with half the steam. Then you can condense to recover the energy from the rear engine's steam. This overcomes the direct problems seen with the Erie triplexes. Result: more efficiency, more complexity.

 

Not sure I'd want to drive something that much of a juggling act with loosely coupled goods wagons.

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1 hour ago, DenysW said:

There also seem to have been several Toton-Cricklewood routes, at least in Leicestershire, and I find it difficult to believe the riskier approach would have been available on all and for all timings.

 

I'm fairly sure the standard route for mineral workings was via Trent and the Midland Counties line, rather than via Nottingham, Melton, and Manton.

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9 hours ago, The Johnster said:

But there was also the 'Windcutter/Annesley Runner' method, in which a through road was established over a long distance and, in the interests of keeping the couplings tight, the loco pulled consistently all the time and speed built up, to some surprising figures in the case of the Windcutters, despite the 9' wheelbase wagons, and predicated on the concept of having a long time available to gently slow the train down at the end of the adventure.  This worked well on the Great Central where traffic was light in the 60s and the method was not only possible but arguably the best use of the resouces.  Risky, though...

 

I have to ask what the point is. Coal is not a rapidly perishable commodity and if traffic on the route is light then pathing isn't a particular problem either.  Why not just turn the line into a coal conveyor run at a comfortable and economical speed?  Was it an attempt to minimise crew costs, or what?

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3 minutes ago, Flying Pig said:

I have to ask what the point is. 

 

Advantages:

  • reduced turn-around time means less rolling stock - i.e. less capital tied up, reduced staff costs;
  • a good run at the banks.

Disadvantages:

  • higher maintenance costs;
  • inability to stop safely in an emergency.

Anything else?

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