Sir Nigel Gresley - The L.N.E.R.’s First C.M.E.

The foibles of secondary evidence are that it is a subjective - rather than objective - view of a locomotive and its capability. A case in point is the GWR whose attachment to fully inside motion would make maintenance staff at other companies blanche with fear but the GWR maintenance team accepted the task and "made it work". I have previously alluded to Haymarket where the maintenance staff maintained the Gresley conjugated valve in a way slightly different from the recommended practice hence improving the reliability above the average IIRC. For any type of transport machinery whether it be car, bus or locomotive there will be different opinions regarding maintenance and operation that - combined with the allotted tasks for a depot - will give variations in the experience of locomotive workings at individual depots. Agreed that Board minutes will not analyse individual depots but they will be provided with sufficient statistics to decide whether a class of locomotives meets its specified allotment of tasks with ease or difficulty thus knowing the degree of success that the locomotive meets. In regards to the P2 / A2 individual sheds might praise the P2 for its ability to meet the task but quibble about the availability (and the maintenance effort required) to meet the task. I may be posing a question previously answered but I wonder if some authors have confused ability with availability when discussing locomotive performance.

 

Academics would disagree with you, there are levels of evidence and there are circumstances where primary evidence very clearly disproves secondary evidence. All well and good talking about being "too dogmatic where there is conflicting information" but sometimes a spade is spade, and evidence that is corroborated by other evidence will ultimately disprove conflicting secondary evidence.

Wait for Tim Hillier-Graves book on Bert Spencer, due this year I believe. That will illuminate the primary/secondary debate even more.

I've no doubt of the veracity of that information: as it is discussed in the LNER's locomotive committee minutes. Primary evidence, people...

The 2-8-2T and the 4-6-0 are both included in respective RCTS LNER "Green Book" volumes as line drawings. They are reported as having been serious discussions in the development of some locomotive classes under Gresley. There's no reason to doubt them particularly, but they are very much still born ideas.

 

They must have spent a lot of time in a state of terror then! Consider the number of older classes with inside Stephenson and even inside cylinders on all the lines right through the 1950s.

 

The A.F. Cook referred to in post 658 is presumably the same A.F. Cook who wrote two of the RCTS books on LMS locomotives: Raising Steam on the LMS and LMS Locomotive Design and Construction.

 

Absolutely agree Fred. Can confirm!

The P2 issue has its waters muddied by a number of secondary sources, some of whom aim shots at Thompson, for instance, that are completely misguided. I think you are being quite kind and I would not be so kind with my analysis, I am afraid, after ten years of research writing the Thompson book and now two years researching and writing the Gresley book.

 

After 1900 under the Wordsells and Raven the typical layout of the largest North Eastern Railway locomotives was three sets of Stephensons valve gear between the frames, together with the inside piston rod, slide bars, crosshead, connecting rod and big end - some people were eloquent on how readily accessible it was for inspection and oiling.

 

In view of some of the comments on oiling round more than a few pre-Walschaerts classes, do any drawings for the latter Worsdell or Raven 3cyl locos survive to demonstrate why that might have been so?

 

You do not need drawings. Photos will do.
The Midland Compounds , NER Z Atlantic,NER Pacifics and NER S3/B16 drove to the first driver axle and there was no outside Walshartst to block acces-

Thompson A2 Forhjul by Hermod posted May 22, 2019 at 9:05 AM

According to a leading NER draugthsman,mr Heppell the scheme for all these locomotives came from mr Heppell and was much better than the original scheme from mr Smith.
Ken Hoole`s book N.E.R. locomotives have drawings.
It is a great loss for humanity that Hoole did not go further than grouping.
He would have known who did best job with B16 .
Heppell/Worsdell/Stamer/ Raven or Gresley or Thomson.


https://ner.org.uk/product/north-eastern-locomotives-a-draughtsmans-life-ebook-new/

 

I have to be frank, I do not want to see scores of "never wuzzas" cluttering up this thread Hermod, with respect.

However, thank you for the pointer on the book on Hoole, that will be an interesting read.

 

I hope someone can provide some drawings or photos. Could someone in the Darlington area pop into the Head of Steam museum and take some pictures of the NER 0-8-0 there? As I mentioned in post #645, it's fairly easy to see all the bits because there's a fair amount of empty space under the boiler; and by the same token they should be reasonably easy to get at for oiling.

 

Launching a thread on NP is akin to playing poohsticks. You have no control of where it goes.

 

If there is someone alive that has oiled up a LMS compound and a SR School we can have a real good judgement?

 

With some Schools still working on heritage lines there must be plenty of such people; but how is a School relevant, with only one set of inside valve gear (and that presumably Walshaerts, driven from a single eccentric)?

 

Most UK 4-4-0 had two cranks and four eccentrics inside the frames but were crew expected to go between frames very often?
If not then the Midland /NER three-cylindered would need even less between frames tickets but the Schools many more as the Walshaerts things were blocking acces road?

 

Crews would go between the frames on any loco with inside cylinders daily to prepare. It’s a fact of life which Bulleid (amongst others) tried to remove, but ultimately it took dieselisation.

Even now on preserved lines, drivers still try to stop in a position where the cranks are “set right for oiling”. It’s also noticeable how, on otherwise potentially similar tank engine and tender engine designs, the tender version is often easier to oil up because most of the motion can be reached from the running plate and leaning over the top. On an equivalent tank engine, unless the tanks have cut outs, often you have to go underneath and the wiggle up between the firebox and crank axle to access the oiling points on the crank shaft.

Tom

 

On the LNER J 27 you can set the cranks so that they are accessible from on top. Well, that would be the case if there wasn't a reversing rod in the way on the right hand side and the sanding linkage on the left hand side. That means it's easier to go between the frames and heave yourself up between the axle and a rather hot throatplate to oil it up. At least, I find that the easier option. Either that or get the fireman to do it as he's usually younger and more agile than me.

 

In my final stage of preparing graphs and stats for the Gresley book, I have been able to do a little work on the A1s vs A2s comparison tests of 1924, with 2404 vs 1472:





But the most interesting aspect of these tests, for me personally, was a bit of a rabbit hole I went down when I read some of the secondary evidence decrying the Gresley loco for the lower boiler pressure when running the test trains. So I put this table together:



So the same two locos did the same tests, roughly, with only minimal train weights difference between them, and one locomotive did the same work at a much lower overall boiler pressure and with much better overall fuel economy.

I think this truly puts paid to any thoughts on the Raven A2 being potentially a match for the Gresley locomotive. It was powerful, no doubt, and I can find no evidence to suggest it wasn't pretty reliable too, aside from the rear trailing wheels prior to the cartazzi being fitted. But it clearly was a dead end, and the Gresley loco wasn't.

 

Water per work done were almost identical.
We lack calorific value of steam to judge machinery efficiency.
It is not unlikely that Raven (if he had been CME) could find a sweet spot load/speed where A2 boiler efficiency was better than A1.
But A1 looks much better.
There is really to few data points to conclude that an A1 was better than an A2.

 

If this was with the original A1 design before the major improvement when long-travel valves were fitted, it makes the A2 look very poor for efficiency despite its higher working pressure. What could have made it so bad?