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2 hours ago, jamie92208 said:

  It's also interesting to look at the lines that different companies built and how they were engineered. I'm no expert but the LNWR's line up the Spen valley, in part, built around 1900 had gradients as steep as 1 in 70 and required double heading till the end of steam.  The Midland's proposed line of 1897 up the same valley had a ruling gradient of 1 in 200. 

 

The Stephensons, Father and Son, were wedded to the idea of keeping gradients down even at the expense of longer routes and missing out major traffic centres - e.g. Sheffield not on the North Midland. Their lines usually have a significant summit tunnel - Kilsby, Clay Cross.

 

Locke started out as George Stephenson's pupil but following something of a palace revolution on the Grand Junction took over the engineering of that line. He displayed his independence and confidence in the development of the locomotive - overconfidence, perhaps - with less fear of gradients. His lines are characterised by a gradient profile that looks like the roof of a house, eschewing the summit tunnel - Grand Junction, Lancaster & Carlisle, Caledonian - there is no tunnel on the WCML north of Stafford! Undoubtedly cheaper to build - which goes a long way to explain the success of the partnership of Locke & Errington - but more expensive to work. Brunel started out with the Stephensonian philosophy but his inventiveness led him towards a Lockian approach, which, he realised, would work if the source of power was fixed, with power being transmitted to the train by some means. Unfortunately his engineering materials weren't up to the task and his system was also fatally flawed by the power limitation of a pressure difference of less than one atmosphere available. From this perspective, it's hardly surprising that the WCML was electrified long before the ECML.

 

After the crash of 1846, money was tight, so the Lockian approach ruled by necessity - right down to the 1860s. By the 1890s, ideas had changed again - maybe more capital was sloshing around, certainly tunnelling techniques were more advanced. Studying a list of long railway tunnels, it's notable that they fall into two main groups by date: 1830s/40s and 1890s/1900s with rather fewer in the intervening years.

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When challenged over the ruling gradient on his suggested route for the Caledonian line North of Carlisle, Locke remarked that with the advances in locomotive power being made, the problem would not be getting up the hills but slowing or stopping on the way down (not a verbatim quote but a paraphrasing).

 

Dave

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11 hours ago, Dave Hunt said:

The threads here are fascinating and informative but I just want to point out that it is an indisputable fact that notwithstanding any evidence to the contrary the Midland was the finest railway on planet earth. In stating this I am completely unbiased in any way.

 

Dave Hunt

Chairman, Midland Railway Society.


Facts are fine but don’t let them get in the way of a good story! It is worth remembering that the G&SWR had a close working relationship with the Midland and almost took them over, 3 times!  
 

Ian Middleditch,

Chairman, Glasgow and South Western Railway Association.

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Comparing Locke and Brunel as Dave did above is in my mind a heresy but not in the way that most people will think. Brunel is often described as a genius, which IMHO he was not. He was a brilliant structural engineer but his ideas for locos were a disaster, his choice of gauge was poor and cost the GWR a fortune, his treatment of contractors was scandalous, he spent a fortune on the relatively untested concept of atmospheric propulsion and his schemes went massively overbudget. And then there were his ships which contained some good conceptual ideas but were also flawed.

 

On the other hand, Locke built railways on time and to budget. There were no flashy expressions of ego but instead as an engineer he did his job and did it well. If I was a shareholder, I would be much happier if I invested in one of Locke's schemes. He deserves to be much more famous than he is but as always history favours the showman.

Edited by John-Miles
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I do think Brunel's willingness to experiment with alternatives to Stephensonian orthodoxy is admirable, even if his ideas were flawed - there were some worth-while ideas whose success in practice was frustrated by the technology to hand; unfortunately he was indulging his experiments at the investors' expense. Brunel and the Stephensons shared some common misconceptions such as the need for low centre of gravity and rigid permanent way. The Stephensons and their circle were successful through the application of hard-won practical experience whereas Brunel was close to the French tradition of state-sponsored engineering education, although neither he nor his father were products of the Grandes écoles - Brunel was educated at the Lycee Henri IV in Paris, a very prestigious school, but as a foreigner was ineligible for the École Polytechnique. Brunel moved in an altogether different social circle.

 

Topic relevance: Brunel was engineer of the Bristol & Gloucester and hence several of his delightful country stations passed to the Midland.

Edited by Compound2632
Clarity
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4 hours ago, Compound2632 said:

The Stephensons, Father and Son, were wedded to the idea of keeping gradients down even at the expense of longer routes and missing out major traffic centres - e.g. Sheffield not on the North Midland. Their lines usually have a significant summit tunnel - Kilsby, Clay Cross.

When they built the L&B, they avoided Northampton because as one of them commented, there was no difficulty getting trains into Northampton, only in getting them out again!

(There is no truth in the often repeated rumour about the town council protesting about the railway: they wanted it, and it is still an important generator of passenger train revenues.)
Of course, the 1:200 gradient out of Castle Station as was eventually created and which followed a speed restriction through the point work at the south of the station, meant coal trains headed south were often reduced to a crawl by the time they got to Roade, but that must have been an impressive sight.

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29 minutes ago, Compound2632 said:

Brunel's willingness to experiment with alternatives

The problem is that he did it with other people’s capital, intended for an overall purpose (e.g. a railway between two points) rather than as a proper experiment.

 

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24 minutes ago, Regularity said:

When they built the L&B, they avoided Northampton

Yes it would have been one hell of a detour between Lynton and Barnstaple!

 

I have been following this thread because it is inhabited by grown ups who are producing a very interesting read, especially on the technical side.

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The nature of the lines that engineers such as Stephenson, Locke, Brunel et al built affected the engines that ran on them. This, together with the way the operating people ran the railway, nudged the pre-grouping locomotive engineers consciously or subconsciously into designing engines that suited the characteristics of their railway.

For example, the operators of flat routes invited their engineers to develop engines that could haul heavy, fast trains. This necessitated developing high horsepowers at speed which in turn demands a large steam circuit (and not just the valve lap) so the necessary large steam flow will not lose too much pressure on its way to and from the cylinders.

On railways, such as the Midland, forced to haul their trains up steeper gradients than their competitors, the size of the steam circuit was of less importance because their engines tended to make their greatest effort lifting the train against gravity rather than overcoming air resistance. Although, an engine that has to haul a up a hill may still have to develop a quite high power despite pulling a lighter train, engine speed usually fell while cut-off was lengthened. Both of these factors tending to reduce the throttling the steam was exposed to, so a smaller steam circuit sufficed. Once a flatter portion of line was encountered the smaller circuit was large enough for the engine to pull its lighter train at as a high a speed as perhaps the more generously proportioned one.

417583337_Georgev2P.jpg.7c9db6e20976bbecdc1c38df909dfd22.jpg

We may see this difference comparing a Midland express engine steam circuit with one carried by an equivalent LNWR engine. Both are essentially short-lap engines. While the lap fitted to the George the Fifth was originally 1¼ins because they were fitted with Joy valve gear (constant lead) at 20/25 per cent cut-off the port openings would not have been that dissimilar to those of a 483 class 4-4-0, which were fitted with Stephenson’s gear (variable lead). Thus, we may deduce most of the difference in performance displayed by the two classes was due to the sizes of their respective steam circuits.

If a ‘George’ was working with say a pressure drop between the boiler and the steam chest of 15 or 20lbs, then in the Midland engine, the equivalent drop will have been 45 to 60lbs/sq in – hence why red engines didn’t produce high powers at high speeds.

Another simple but crucial relationship that affected locomotive performance was the water consumption. Mr Rous-Martin described how a Class ‘T’ 4-4-0 Nº 2596, took the 9-30 am fast Scotch express weighing approximately 300 tons, from St Pancras to Leicester (99 miles) in 111 minutes 34 seconds - gaining nearly 1½ minutes on the booked time in the process. He observed the run could have been 2 or 3 minutes quicker but for shortage of water, which forced Driver Turner to shut in for the latter part of the journey to eke out the remainder. Horsepower estimates confirm there would have been precious little water left in the tender (5-10%) by the time the train had reached Leicester, as was confirmed by Mr Rous-Martin:-

“Indeed, I was assured that even more could have been done had the locomotive been fitted with a larger tender, like the ‘2601’ and ‘2606’ Classes”

This is enginemanship of a very high order, the more so when we remember tender tank contents gauges were not fitted until the railway companies were compelled to do so by the BOT in 1904. That rash of bogie ‘water carts’ which appeared at the turn of the century were the inevitable accompaniment to building more powerful, saturated locomotives. In the absence of water troughs, engines had to lug 20 and more tons of water behind them, in order to make non-stop journeys of 100 or 120 miles while pulling heavier and/or faster trains.

LNWR engines running from Euston typically encountered water troughs every 40 miles or so thereby giving the crews ample opportunity to top up the tender tank. The knowledge that they would not run out gave LNWR enginemen the confidence to work their charges in a way that has whet the appetites of contemporary and later locomotive enthusiasts. The Drawing Office reflected this, by providing (for the day) good exhaust systems, generously proportioned internal steam pipes and large free gas areas through the boiler barrels, which supported high combustion rates.

image.png.ca1d6cc4b5a18747016cb99bf857d359.png

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Finally, it was pointed out a 483 class 4-4-0 based on the power calculation was a Class 3 engine, so I thought you might like to see these two tables. The first gives the loads for the Special Limit trains, which were faster, between London and Leicester. The 483 4-4-0s were lumped in as Class 2 engines. The second table records one of these engines taking a Class 3 Special limit Load and gained 3¾ minutes on the way.

At this point I feel I have said more than enough.

 

Crimson Rambler

 

 

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The potential MR/GSWR amalgamation is a fascinating subject and one which I have been interested in for a long time. I am convinced that the Midland saw it as a major step in its aim of eventually becoming the London, Midland and Scottish Railway (with Northern Ireland thrown in for good measure) half a century before that name actually came about. It spent a huge amount of time, effort and money trying to get a proper foothold in Scotland as well as going to great lengths to get a major share in Ireland. As I see it, the traffic arrangements with the NBR were part of the process along with amalgamation with the GSWR and designed as a prelude to getting the NBR into the Derby bag too, possibly followed by the GNSR. Why otherwise would the Midland have chosen to be a major shareholder in the Forth bridge? Add in the involvement with Stranraer, which unfortunately didn't fulfill its promise, and the Midland board must have been frustrated many times over, eventually settling on developing Heysham instead (once its dalliance with the FR had been ended). Of course, it is intriguing to ponder on how much of its ambitions the Midland would have satisfied even at the late stage of its final attempt to get its hands on the GSWR had Sir Matthew Thompson not been taken ill and died when he did.

 

As I stated, a fascinating subject.

 

Dave     

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6 hours ago, Happy Hippo said:

I have been following this thread because it is inhabited by grown ups..........

 

My wife would take severe issue with you on that, Richard.

 

Dave

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49 minutes ago, Crimson Rambler said:

We may see this difference comparing a Midland express engine steam circuit with one carried by an equivalent LNWR engine. 

 

Now that really is waving the red rag to the Crewe bull!

 

49 minutes ago, Crimson Rambler said:

This is enginemanship of a very high order, the more so when we remember tender tank contents gauges were not fitted until the railway companies were compelled to do so by the BOT in 1904. That rash of bogie ‘water carts’ which appeared at the turn of the century were the inevitable accompaniment to building more powerful, saturated locomotives.

 

I didn't know about that BoT requirement. Presumably it was partly in response to the 1898 case of the Caledonian engineman who was killed by his head striking a bridge while climbing back over the water-cart tender of his Dunalastair II, working the Royal Train?

Edited by Compound2632
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35 minutes ago, Compound2632 said:

I didn't know about that BoT requirement. Presumably it was partly in response to the 1898 case of the Caledonian engineman who was killed by his head striking a bridge while climbing back over the water-cart tender of his Dunalastair II, working the Royal Train?

 

There was also a similar incident in 1901 on the Caley Glasgow - Carlisle mainline (pg. 200 of The Springburn Story) , so the BoT requirement may have been the result of multiple such accidents across several companies.   The Royal Train accident might have brought the issue to greater prominence mind

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18 minutes ago, Caley 439 said:

 

There was also a similar incident in 1901 on the Caley Glasgow - Carlisle mainline (pg. 200 of The Springburn Story) , so the BoT requirement may have been the result of multiple such accidents across several companies.   The Royal Train accident might have brought the issue to greater prominence mind

 

That is the incident I was actually thinking of, because the driver had been up on the tender to check the water level. In the Royal Train fatality, it was to sort out a problem with the communication cord.

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Sorry I don't know how to put in the necessary link but if you Google Railway Employment (prevention of Accidents) Act 1900 you will find the details.

 

The first six pages can be largely disregarded it is the schedule of twleve items on page 7 that is important - and item 10 concerned the arrangement of tool boxes and water gauges on engines - tool boxes had to be accessible. David Tee told me it included to introducing water contents gauges on tenders.

 

Crimson Rambler

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I had a quick look at the pdf - the Act enables the BoT to make rules on the topics mentioned in the schedule. Not all such rules would have been drafted instantly, hence the 1904 date for the rule on tender water gauges.

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Just catching up because the dreaded "list " emerged a few days ago and I have been forced to do some decorating.

 

First the Stephensons, under-rated in my opinion. George put a huge effort into persuading the L&M to adopt locomotives rather than stationary engines. This was a huge step forward and given the state of locomotives at the time a bit of a leap of faith but it paid off handsomely. Robert with  Fairburn invented the box girder, a type of bridge which has since been used all over the world. Interestingly it has been contrasted with Brunel's Saltash bridge which is always quoted as being cheaper but I can't find any reason why the Saltash form of construction has never been copied. I can guess that it was partially a suspension bridge which has never suited rail traffic.

 

Secondly - steam circuit - what exactly is meant by this. The pipe from the regulator to the cylinders. I believe the diameter used by the Midland was relatively small which would lead to higher friction losses. Does it also include the design of the regulator, which again could lead to pressure losses. As the valves come in for separate consideration are these excluded.

 

When the Midland invested in the Forth Rail bridge, its chairman was a Scot and so maybe this was part of the reason?

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4 hours ago, John-Miles said:

When the Midland invested in the Forth Rail bridge, its chairman was a Scot and so maybe this was part of the reason?

 

A small part of the reason maybe but buying a third of it would seem to be a bit excessive just to show solidarity with the descendants of Braveheart and the rest of the Derby boardroom may have had something to say about it.

 

Dave 

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I was fiddling about with the power formula, and I decided to try the L&YR Class 28, a 3F. The class had the following dimensions:

180 PSI boiler

Two 20.5"x26" cylinders

61" drivers

 

Piston speed:

(2 x 26/3.14 x 61) x 25 x 88 = 594

 

Checking the curve, the MEP is about 42.5 - 0.425 x 180 = 76.5

 

2 x 2 x pi x (20.5/2)^2 x 26 = 34,308.39

 

34,308 x 76.5 / 3.14 x 61 = 2,624,591.84

 

2,624,591.84/2240 = 6.1 long tons

 

In other words, a 5F. 

Can anyone tell what I'm getting incorrect?

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7 hours ago, GWRSwindon said:

I was fiddling about with the power formula, and I decided to try the L&YR Class 28, a 3F. The class had the following dimensions:

180 PSI boiler

Two 20.5"x26" cylinders

61" drivers

 

Piston speed:

(2 x 26/3.14 x 61) x 25 x 88 = 594

 

Checking the curve, the MEP is about 42.5 - 0.425 x 180 = 76.5

 

2 x 2 x pi x (20.5/2)^2 x 26 = 34,308.39

 

34,308 x 76.5 / 3.14 x 61 = 2,624,591.84

 

2,624,591.84/2240 = 6.1 long tons

 

In other words, a 5F. 

Can anyone tell what I'm getting incorrect?

 

Have you checked the boiler power calculation? What is the grate area?

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The grate area of the boiler carried by the LYR class 28 was 18.75sq ft, so at 40ihp/sq ft that gives 750 horsepower just making the engines Class 3 for power.

 

The Great Eastern, for example, built a couple of powerful 0-6-0 classes - J19 and J20.

On Nationalization the former was class 4F and the other 6F. In 1953 both were reclassified 5F which I guess was when BR introduced its modified system - or were there complaints from the operating people?

 

Crimson Rambler   

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