Francis Webb,good or bad?

It's more complicated than that -- all the vehicles in the train could be switched between simple and automatic, and were so switched at various points of the journey. From the report:

So the train had been worked as both simple and automatic on the same trip - no wonder the driver got confused.

 

I'm even more confused than him, since an automatic brake vehicle won't work with simple vacuum - and vice versa.

 

Possibly prompted by this discussion I have again pulled out John Chacksfield's 'F.W. Webb - In the right place at the right time' (2007) Oakwood Press, Usk ISBN 978 0 85361 657 3. It's good, but after all the negative narratives of the man, possibly errs in the opposite direction.

Two paragraphs are quoted about his involvement in carriage design, whose construction was of course at Wolverton, not Crewe, so not directly within his sight:

"By now Frank was heavily involved in the design and development of the express compounds. The story of these locomotives is such that it warrants a Chapter of its own to clearly describe their development. But before launching into that, there is one crucial feature to be noted, that of the developments in carriage production at Wolverton. This was under Richard Bore who, although he was the Carriage Superintendent in his own right, worked closely with Webb on matters associated with carriage design. When Webb assumed office it was not long before he and Bore began to discuss how the carriage stock should progress. Bore was strongly in favour of four- and six-wheeled vehicles, these being relatively light and inexpensive to construct. He also was an opponent of the use of bogies. However, this latter trait was not too much of an embarrassment as, up to his retirement in 1886, the bogie vehicle was a relative rarity in Britain. Frank Webb enthusiastically encouraged this thinking, but eventually realised that eight-wheeled stock was inevitable. The outcome was that unique eight-wheeled carriage with the inner axles rigid and the outer ones incorporating his radial truck to enable curves to be safely negotiated. The first examples were of 42 ft length and this type of chassis was applied to passenger carriages, sleeping cars and Post Office vans, of which many examples served for over 40 years. Frank supported his backing of Bore by claiming this type of eight-wheeler reduced the rolling that was often associated with early bogie vehicles.

On Bore's retirement in 1886, he was succeeded by C.A. Park who advocated the introduction of bogie stock, accompanied by a lengthening, first to 45 ft in 1896, then to 50 ft by the following year, for standard vehicles. He had taken note of the growth of passenger traffic demands. This trend, however, contributed towards one major effect - the increase in amenities being provided for the passenger meant that the tare weight, in terms of weight per seat, grew dramatically. Train weights were, in the 1890s, to grow substantially and here we come to a point where locomotive performance, in terms of hauling power, was beginning to be outstripped. Problems lay ahead, particularly with the added urge to increase speeds overall after the 1888 Races to the North."

 

The vehicles -- not just the locomotive -- could be switched individually between the two systems.

 

The same book answered another question: electric v gas coach lighting. Although no date is given, apparently 'Problem' No. 44 Harlequin was fitted with a three-cylinder Brotherhood engine to drive a generator mounted on the tender in order to provide electric power for carriage lighting. This ran to three iterations, but the cost caused the experiment's abandonment. Before this is given as another example of Moon / Webb parsimony, all other railways refused to move from gas lighting for exactly the same reason. I believe the first electrically lit trains were the L&YR Liverpool - Southport sets, the first main-line electric trains in the world, and thus had a readily accessed supply. Although the risk of fire was present with gas, the outbreak of this was quite rare in accidents, although this was of little comfort to those burned alive. The Midland suffered three such conflagrations: Ais Gill, Hawes Junction and, post-Grouping, Charfield. The Caledonian of course had the tragedy of Quintinshill, Fire was involved at the LNWR's accident at Ditton Junction, although the biggest one at Abergele wasn't due to the lighting.

 

Just out of interest do we know how much an Anglo-Scottish express in say 1875 would have weighed, in contrast to say one in 1900. And average speeds.

I think there is a broader point here - that Webb was trying to come up with solutions, whereas the Midland's solution was to simply put another loco on the front. (There is a poem about the Midland in the LMS 150 book)

 

The Scotch expresses in 1875 would be in the range of 75 tons (very light) to 150 tons, although I think 100-125 was more typical. By the turn of the century the stock was corridor on four-wheel bogies, and 300 tons and more is quoted.

Remember that in those days on the LNWR train loads were given as number of vehicles, where a four-wheeler was 1; six-wheeler 1.5 and a bogie vehicle equal to 2. This doesn't always work out in actual weight. And while this is often derided today it had a point: at low speeds, accelerating from rest and climbing gradients, the weight was the main criterion; but at speed on level track aerodynamic resistance became the issue. Weight had no bearing on this but the frontal wind resistance of each vehicle did.

 

And, particularly in the days of grease axle boxes, rolling resistance - hence counting a six wheeler as 1.5.

In a slightly different context, I believe the Stroudley 8 coach block sets introduced in the 1870s were about 55 tons and seated 400 passengers - obviously in rather more spartan (bare wooden seats) and crowded conditions than a mainline train. That’s roughly 7.5 seats per ton of tare weight. To take the same number of passengers in a mixed rake of Mark 1s you would probably be at somewhere in the region of 1.25 - 1.6 seats per ton of tare weight. Or looked at another way, in the space of 75 years, the train weight goes up four or five times for the same number of seats. A major part of that rise was roughly in the period 1890 - 1910 or thereabouts.

Tom

 

The chain brake system started to be developed in the 1840s, some sources say that it began in 1840. Francis Webb returned to the LNWR in 1871 after working for the Bolton Iron and Steel Company as the manager from July 1866. During his period as works manager at Crewe in 1861 he was responsible for the installation of Bessemer converters at the works and the subsequent start of steel production. Webb must have learned much about steel production whilst at B.I.S. and this knowledge must have been very useful to the LNWR in terms of the quality of the material that their in house steel works could produce. Maybe Webb's locomotives did appear to be lightly built but the quality of the materials that were available maybe a factor here. Better material allows you to use less of it for the same or even superior result than would the case with a lesser quality material.

It would be 1875 when the Clark-Webb chain brake was perfected following on from the Clark and Wilkins variant of 1859 and in the June of 1875 a series of brake trials took place at Newark on the Nottingham-Lincoln branch of the Midland Rly. Various braking systems were involved in the tests, air, vacuum, hydraulic and mechanical and the results placed the Westinghouse air brake to be superior to the others but the train weights were not identical, neither were the train speeds at point of braking and some trials were on dry rail and others on wet but the Clark-Webb system was not disgraced. Other trials followed not only in the U.K. but also across Europe with the L & Y trials taking place in July 1880.

It would be in the 30th August 1889 when the Regulation of Railways Act received Royal Assent and this act empowered the Board of trade to require all railway companies to adopt block signalling on all passenger railways, to provide interlocking points on all such railways and to provide continuous brakes for use on all passenger trains. These brakes were required to be instantaneous in action, self applying in the event of any failure in continuity, capable of being applied to every vehicle of the train and to be in regular use daily. The Abbots Ripton accident took place in 1876 and the Armagh disaster 12th June 1889.

The Midland took up the air brake but found it to have serious reliability problems and so abandoned it and went over to the automatic vacuum brake. Board of Trade records are revealing when it comes to the two types, 71 million miles on air brakes gave rise to 3,900 failures and 42 million miles on the vacuum system 519 failures.

The Clark-Webb brake worked reasonably enough but the company realised that it needed updating and the report into the Liverpool Lime Street incident of July 1884 is critical of the system and suggests that it be replaced. The Carlisle report into the accident of 13th August 1883 was critical of the lack of compatible continuous brake system being fitted to a LNWR locomotive. The LNWR hung on to the system for too long but the company had an enormous fleet of vehicles to deal with and how much they knew of the experience of other companies and their applications of continuous systems I do not know but you can guarantee that they would not have wanted the Midland experience. Richard Moon continued to defend and justify the chain brake system to the shareholders, meanwhile the people at the workshops were organising the replacement.

 

Thanks. I often wondered what was meant when drivers in the accident reports would say 18 equal to 24.

Of course increasing train weights impacts upon stopping. Harder to stop a 300 tonne train than a 100 ton train.

So you have the designers of the Webb era being confronted with a massive change in circumstances which is posing serious engineering challenges to them at a number of levels. Webb wasn't the first designer to go down a dead end when confronted with changing circumstances.

 

That's only true if the braking is from the engine only, e.g. prior to the requirement for continuous brakes or on an unfitted goods. With continuous automatic brakes, it is easier to stop a heavy train than a light one. This is why speed limits for light engine movements are lower than for a loco hauling stock.

 

Yes, sorry I wasn't quite clear, but my point was that heavier loads meant that you had to have continuous automatic brakes. The lines had to change. In some ways, this is an inversion of the normal narrative of loco design driving everything forward, when really it is improvements in carriage design that are changing the landscape.

 

As well as the increase in tare / passenger, shouldn't some allowance be made for: 1) the steam demanded by continuous brakes, and 2) steam heating. Both tax the boiler without helping the power output.
Pat

 

Actually, the first individual electrically lit carriage in the world was a Pullman car on the L.B.S.C.R By the time of Stroudley's death in 1889 not only was an entire set of Pullmans fitted with his dynamo operated system but several suburban sets as well. Unfortunately, his successor was less enlightened (sorry) and went over to gas although there were no incendiary consequences in this case. A similar system to Stroudley's was used by the G.N.R.I.

 

It’s an often forgotten point. I seem to recall there is a discussion in Langridge’s book about the design of the prototype LMS diesels, and how powering the auxiliaries gave particular design problems, whereas the capability of a steam locomotive to do so had been pretty well taken for granted.

Tom

 

I don’t have it to hand but I read something about the LNWR and using footwarmers for heating. I don’t know when steam heat was widely adopted.

 

The GW had a viable (but complex) steam heat system in use by 1896 & in 1903 conducted a test:

Attached are some pdfs of talks given to the Swindon Engineering Society by Churchward & F.W. Marillier.

 

Eric Langridge's comment concerned the use of ETH from diesel and electrics, how much of a power loss to wheels was entailed, and that led to his comment aboiut the steam loss from a locomotive's boiler having been so underestimated.

 

That lines up pretty well with the consumption figures I've seen quoted for a King Arthur (453 himself, no less) on twelve bogies, of 1600 lb/hr, so 160 gal/hr. If those were 57' LSWR Ironclads you could claim about 112 gal/hr as equivalent consumption, but either way it's the same order of magnitude. The same source (Phillipson, Steam locomotive design: data and formulae) has about 30 gal/hr for a vacuum brake system.

One advantage for the steam engine in providing heat is (perversely) the disadvantage @Jamessquared often mentions when discussing their thermodynamic efficiency. For producing power the latent heat of evaporation is basically lost, whereas I believe a reasonably efficient steam heat system will aim to have the steam condensing in the radiators; you'll still get a perfectly adequate radiator temperature. I doubt King Arthurs ever had controlled testing done, but I'm going to guess (based on near equivalent classes) their maximum evaporation will have been order of 25000 lb/hr, so about 6.4% of total power potential going to heat. The numbers for electric train supply power on diesels are usually much higher than this as a percentage of engine power, about 330kW for a Class 47 out of 1860kW engine power, more like 18%.

 

With air con stock you could hear when the ETH was briefly turned off when departing from stations