Imaginary Locomotives

[The Johnster]

26 minutes ago, DenysW said:

The conventional-bunker LMS Garratts had an ineffective tarpaulin-style arrangement to stop coal dust blowing into the cab. So it seems that although Garratts could run either-end-first, you'd rather not make them do so at speed.

 

Which does not sound like a problem beyond the wit of man to solve...  but high-fronted tenders were rare as rocking-horse doodoo in 1924, and off-hand I can only think of the Gresley A1 pacifics that had anything like that.  Tender-first running at speed was not really foremost in anyone's mind, and it seems that Beyer-Garratts were not thought of as tank engines; indeed, big tank engines on fastish outer-suburban work were usually turned to run smokebox-first despite the advantage of bunker-first running being clear of any exhuast.  If you say a steam loco is running forwards, you mean it is running smokebox-first, despite the concept of 'forwards' being an operational nonsense as applied to a tank engine. 

 

20th-century UK steam-loco design produced some astonishinginly good locos within a restricted loading gauge and axle load limit, but was, even up to 1924, still bound by convention; don't forget it was not very long previously that Dean, Stirling, and Johnson, presented with steam sanding gear, reverted to the simplcity of singles immediately; they looked magificent but were hadly progress!  Railway culture has always been small c conservative; find something that works and stick with it, sometimes long after it has stopped working (pre-Stanier LMS, post-Collett GW/WR, and they weren't the only culprits), and a high-front coal unit for a Garratt was not as likely as it should have been.  The revolving coal bunker was a significant improvement but I'm not sure that was available in 1924...

Edited October 6 by The Johnster

[The Johnster]

22 minutes ago, Compound2632 said:

 

Ah, yes, but then there's the Algerian streamlined Garratts, designed for long continuous runs on a 60 mph timing, with 75 mph top speed.

 

The key word here is 'streamlined', and oil-fired, no coal dust in the well-enclosed cabs.  And those engines didn't exist in 1924.

[DenysW]

6 minutes ago, The Johnster said:

Which does not sound like a problem beyond the wit of man to solve... 

 

6 minutes ago, The Johnster said:

The revolving coal bunker was a significant improvement but I'm not sure that was available in 1924...

My understanding (from Ian Sixsmith's book) is that it was Beyer Beacock's response to feedback/complaints from the LMS in 1927 once the tarpaulin had failed. My belief is that Toton used turning circles, but Brent used turning-chords.

 

Incidentally, my reading of Durrant is that the Algerian streamlined Garrattts were coal fired, with a coal-pusher and two firemen.

[Michael Edge]

The first  Garratts were built with cylinders inboard but Beyer Peacock very quickly changed to fitting them at the outer ends so obviously the above theoretical disadvantages didn't exist. The Algerian ones were the only high speed ones built and they worked well - not Beyer Peacock but proves there was nothing wrong in principle. There were very few 6 cylinder Garratts, the LNER one being the best known but the extra cylinders were at Gresley's insistence and not very succcessful. The only other 6 cylinder ones were built for New Zealand and were so bad that they were cut up and converted into 4-6-2s.

[Compound2632]

4 hours ago, DenysW said:

Brent used turning-chords.

 

At Brent, there was a loop line connecting up and down sides, that ran under the bridge over what became the A406 North Circular. Unfortunately on the 25" map it straddles two sheets:

https://maps.nls.uk/view/103657928

https://maps.nls.uk/view/103657934

I'm not sure when it was built; it's not on the 1894 survey but is on that of 1912. So it wasn't built specifically with the Garratts in mind but rather for getting engines arriving from the north over to the engine shed without crossing the running lines. Turning was an added convenience, but running over the loop line would perforce be tender-first in most cases.

Edited October 6 by Compound2632
removed grammar blurp.

[Michael Edge]

Many other places had nowhere to turn the Garratts, Hasland shed had a special straight road alongside the roundhouses to stable them. On the other hand the LMS Garratts never went very fast in either direction and the LNER one spent half its working life at walking pace....

[DenysW]

53 minutes ago, Michael Edge said:

There were very few 6 cylinder Garratts, the LNER one being the best known but the extra cylinders were at Gresley's insistence and not very succcessful.

I thought that it was simply that he asked Beyer Peacock to replicate the design used for the GNR 2-8-0s, duplicated and mirrored. And that they in turn had 3 cylinders because the Tractive Effort was too much to supply with two cylinders and fit within the LNER loading gauge. I have no opinion as to how well the cylinders fared trying to apply power at slow speeds up the Worsborough Incline. I suspect nothing was/would have been happy.

 

30 minutes ago, Michael Edge said:

Many other places had nowhere to turn the Garratts, Hasland shed had a special straight road alongside the roundhouses to stable them

Agreed, and you do see photos of the LMS Garratts running bunker-first. But I think an appreciable majority are running chimney first - as photographed.

[Compound2632]

2 hours ago, DenysW said:

 But I think an appreciable majority are running chimney first - as photographed.

 

But is that because the photographers thought a Garratt running chimney-first made a better picture? They didn't photograph every train that passed, I presume, so the photographic record is biased.

[rockershovel]

4 hours ago, Compound2632 said:

 

This begs the question of why Beyer Peacock stuck with having the cylinders at the outboard ends?  They built large numbers of successful locomotives with this arrangement.

 

 

But isn't the point that many Beyer Garratts were built for use in places where only poorer quality coal was available, so a big grate was vital to being able to release enough energy? Coupled with either a mechanical stoker or a colonial attitude to native labour, the firing rate wasn't such an issue.

I've seen accounts of the very large Beyer Garratts built for East and South Africa running with two, or even three firemen. 

[Ohmisterporter]

AIUI the SAR class GMAM Garratts were always run bunker first due to the many tunnels they ran through. They also pulled a water tank behind the loco as they traversed long stretches of waterless terrain. As an aside, I recall an American enthusiast saying that the USA did not like Garratts or other tank engines because as fuel and water were used the weight and tractive effort were reduced. It was pointed out that diesel locomotives do the same thing and have done rather well in North America.

[Mol_PMB]

4 hours ago, Michael Edge said:

The first  Garratts were built with cylinders inboard but Beyer Peacock very quickly changed to fitting them at the outer ends so obviously the above theoretical disadvantages didn't exist. The Algerian ones were the only high speed ones built and they worked well - not Beyer Peacock but proves there was nothing wrong in principle. There were very few 6 cylinder Garratts, the LNER one being the best known but the extra cylinders were at Gresley's insistence and not very succcessful. The only other 6 cylinder ones were built for New Zealand and were so bad that they were cut up and converted into 4-6-2s.

The very first Garratts were compounds, and had a distinctive steam circuit from the regulator down to the rear (high pressure) bogie, then directly forward to the front (low pressure) bogie and then up to the chimney. The long horizontal low-level pipe had to have sufficient flexibility to take account of the relative movements of both bogies, and also tended to act as an unwanted condenser. They were also 0-4-0+0-4-0 and therefore the relatively short bogies didn't have much sideplay, so there was less of a problem with clearance between the cylinders and the carrier frame.

[Northmoor]

32 minutes ago, Ohmisterporter said:

AIUI the SAR class GMAM Garratts were always run bunker first due to the many tunnels they ran through. They also pulled a water tank behind the loco as they traversed long stretches of waterless terrain. As an aside, I recall an American enthusiast saying that the USA did not like Garratts or other tank engines because as fuel and water were used the weight and tractive effort were reduced. It was pointed out that diesel locomotives do the same thing and have done rather well in North America.

Perhaps Yes and No.  A decent size diesel loco might only get a couple of tons lighter in a whole day's work, while a steam loco might go through that cycle several times in a day with its water consumption.  So that would be harder to plan for (when you'd have reduced TE); I suspect the issue was more that hanging a tender on the back wasn't an issue when you had a train as long they typically were in the USA.

[Michael Edge]

The GMAM was designed to be run with a water tanker, the loco only had minimal water capacity in its small tank on the front unit.

[john new]

15 hours ago, Compound2632 said:

 

But is that because the photographers thought a Garratt running chimney-first made a better picture? They didn't photograph every train that passed, I presume, so the photographic record is biased.

A bit like photos of today’s heritage lines - circa 50% of the running is backwards but tender/bunker first images published are a tiny percentage because the blunt end is boring compared to the smoke box end. With diesels and electrics  I suspect the number of A end versus B end leading images will be far closer to 50:50 as the differences aren’t significant other than for the odd class such as a 20 or a 91.

 

Edited October 7 by john new
Typo spotted on re-reading the thread.

[john new]

On 02/08/2024 at 11:08, Compound2632 said:

 

Indeed. Replacing the steam turbine with a diesel engine gives one a much more practicable proposition - as the LMS rightly saw. Better still, remove the generator from the locomotive altogether so one only has to cart the rectifier around. That was generally seen as the ultimate solution from surprising early on - I think there's a remark of George Stephenson's to that effect. The vogue for the pneumatic system was driven by the same idea but rope-worked inclines were the true precursors of the modern electric railway!

For those who like counter-factual history. The case is slim but there is surely a counter-factual case to be made, given proposals like Davidson’s in the early ish C19, that had it not been for the impact of Napoleon and the resultant war forcing the swap from horse to steam locomotives the swap on rails might well have gone horse to electric traction. 
 

The five spurs triggering eras of change in railway evolution were each a significant reaction to changes resultant of political issues:-

• Tudor to Stuart monarchy. James 1st of England was pro coal, Elizabeth had been anti. Huntingdon Beaumont’s taking of rails into the N East were part of expanding to feed that new market.
• Horse to steam - results on the economy of the Napoleonic war*
• Grouping - economic damage of WW1
• Nationalisation - ditto - WW2
• privatisation - political credo espousing reduction of government ownership.

* see New., J (2019) Why displace the horse. In Conference proceedings from Early Railways 6.

[DenysW]

13 hours ago, Compound2632 said:

the photographic record is biased.

Yes, and in several ways. For instance towards full-daylight hours, good/neutral weather, and towards weekends. The first of these is definitely a bias against goods.

 

But I think if a Garratt came along (the most powerful class in the UK seen outside geographically-restricted banking duty), you'd take the picture even bunker-first. After the technology changed from plates, you also want to use a full reel of film (unlike modern digital where there is essentially no limit) in an era where trains were quite widely spaced at most locations. The Sunday pictures from Toton in Sixsmith's book show them lined up ready to go, chimney-first, so the LMS had a preference.

[DenysW]

9 hours ago, john new said:

well have gone horse to electric traction

I didn't think that the technology of electricity generation, and of  >500 kW electric motors were well enough developed in the 1820s and 1830s for this to be true? More like the 1870s as the earliest reasonable?

[Compound2632]

13 minutes ago, DenysW said:

Yes, and in several ways. For instance towards full-daylight hours, good/neutral weather, and towards weekends. The first of these is definitely a bias against goods.

 

But I think if a Garratt came along (the most powerful class in the UK seen outside geographically-restricted banking duty), you'd take the picture even bunker-first. After the technology changed from plates, you also want to use a full reel of film (unlike modern digital where there is essentially no limit) in an era where trains were quite widely spaced at most locations. The Sunday pictures from Toton in Sixsmith's book show them lined up ready to go, chimney-first, so the LMS had a preference.

 

A quick count of a small sample of photographs, those returned when searching on "garratt" in the Midland Railway Study Centre online catalogue, turns up eight running chimney-first and three bunker-first.

 

One also has to consider not only the photographer's bias but also that of the picture editor, if looking at a book. 

 

By the way, the Toton shed photo does show them all chimney southwards?

Edited October 7 by Compound2632

[DenysW]

26 minutes ago, Compound2632 said:

By the way, the Toton shed photo does show them all chimney southwards?

Yes, at least on 27 September 1953. from the Caption: "It will come as no surprise that this is a Sunday, and all the Garratts are coaled up and positioned tank first for the Monday morning job south." However, from the same caption "... but a former fireman at Nottingham, who worked on the things regularly, insists it was pure chance which way round a Garratt would turn up."

[john new]

38 minutes ago, DenysW said:

I didn't think that the technology of electricity generation, and of  >500 kW electric motors were well enough developed in the 1820s and 1830s for this to be true? More like the 1870s as the earliest reasonable?

I agree with you as a personal viewpoint. The beauty of counter-factual thinking however is that the parallel threads don’t have to match and given this is the imaginary locomotives thread we are already hypothesising events that might have/could have but didn’t. 
 

Fact - late 1700s pre Napoleon canals and horses were doing ok until the war economy made the running costs, and availability, of horses problematically expensive. On the historic timeline then cue in Trevithick, Blenkinsop, Hedley/Hackworth et al.

 

Counter factual - no war so far less urgency to bring on steam traction. Bring Davidson perhaps a bit earlier and the rapid development of steam on rails swaps to battery locos, then an earlier gestation of the electrical side.

[Ohmisterporter]

Pictures of Garratts running forwards or backwards on the WHR seem to be equal in number; certainly in my own collection. The possible exception is the Tasmanian Garratt which is almost always pictured chimney first. Perhaps this is due to its small size.

[john new]

15 hours ago, Compound2632 said:

 

But is that because the photographers thought a Garratt running chimney-first made a better picture? They didn't photograph every train that passed, I presume, so the photographic record is biased.

Irrespective of whether they went both north & south chimney first or only predominantly south chimney first, I suspect there is a preponderance of images looking north towards a southbound train. Although I haven’t checked it, with our geographic latitude the better lighting would favour the sun behind the photographer, as it still does for many locations. If the Toton photo does indicate a bias the two factors together would reduce the number of chimney to the rear images.

[Compound2632]

2 minutes ago, john new said:

 

Fact - late 1700s pre Napoleon canals and horses were doing ok until the war economy made the running costs, and availability, of horses problematically expensive. 

 

Principally the high cost of feed due to the Corn Laws? I would be surprised if the military requirement for horses made a very great inroad into the population. Even in the Great War, with the appalling equine mortality on the Western Front, Midland Railway data doesn't show a very great decline in the number of company horses until after the Great War. But that's another example of a technology shift, with petrol motor vehicles becoming widely available.

[Compound2632]

23 minutes ago, Ohmisterporter said:

Pictures of Garratts running forwards or backwards on the WHR seem to be equal in number; certainly in my own collection. The possible exception is the Tasmanian Garratt which is almost always pictured chimney first. Perhaps this is due to its small size.

 

Is there actually the facility for turning garratts at Caernarfon?

[john new]

9 minutes ago, Compound2632 said:

 

Principally the high cost of feed due to the Corn Laws? I would be surprised if the military requirement for horses made a very great inroad into the population. Even in the Great War, with the appalling equine mortality on the Western Front, Midland Railway data doesn't show a very great decline in the number of company horses until after the Great War. But that's another example of a technology shift, with petrol motor vehicles becoming widely available.

Several factors in a perfect storm, re horses, feed shortages & cost, decline in horse quality/availability and if my recollection is correct also some manpower shortages too. Nine years since I did the detailed research so would need to revisit the paper and my notes. 1812 was the interesting year, we were at war with the USA but still buying feed from them to feed the horses in Wellington's Peninsular campaign. The US foreign policy view being keeping the troops in Portugal & Spain meant we would not be sending them across the Atlantic to aid that campaign (We lost that but beat Napoleon).

 

Edited October 7 by john new
Missed a word out (Wellington)