Edward Thompson: Wartime C.M.E. Discussion

As it's Friday perhaps a bit of light relief? This cartoon appeared I think in one of the 1940s modelling magazines - it does show that feelings about Thompson did run high with some enthusiasts at that time - not much changes does it?

Dave

 

Not sure what to make of that. It seems rather petty. Can you point me in the direction of which magazine please? It would make for an interesting discussion of the fairness of the debate!

 

If we're doing the whole photos thing, the similarity in layout of these two Pacific classes is somewhat apparent, amongst other details.

 

I think it was the late lamented Model Railway News, when I was a librarian at Manchester Central Library I photocopied what I could when I knew everything interesting (to me) was going into storage for the major refurbishment of the building. I'm retired now and unfortunately it takes much longer to access historical journals since the re-opening, but I will try to find out.

Dave

 

That is very kind of you Dave, thank you. Model Railway News is one I had heard of - I have a few moth eaten copies from my late grandfather somewhere.

I've changed my mind on the Stirling Single picture - perhaps rather than petty, it represents an indignation at what could be perceived as "uglification" but what I would call austerity. Certainly Thompson's designs were more "functional" than aesthetic - but that's actually why I like them so much in terms of their outline.

 

Reminds more of an Ivatt design than a Thompson one.

 

Not far off this I think:

 

I don't suppose a BR Standard version would be so very different either. Fun game to play though... using my sketches collection I just knocked up a Hawksworth Single. Too far OTT to post though.

 

It does sound like a fun idea for a new thread though

I am thinking of putting together a brief for a new manuscript with bullet points of my current thoughts, for critique and pointers here.

 

i dont recall mention being made yet of Bert Spencer's paper to the Instn Loco Eng in 1949 'The development of LNER locomotive design 1923-1941'.

the following link contains a very detailed account of the meeting:-

http://www.steamindex.com/jile/jile37.htm#222

it is highly relevant to the matter of the Stanier/Cox report. the faults with the conjugated gear are discussed in some detail, but although Cox was present and took part in other aspects of the debate, he remained silent on the matter of the conjugated gear!

it is also interesting to note that Spencer himself outlines the problems with the gear in considerable detail and his words are almost word for word the same as Cox used in his report. now what are we to make of that?

Spencer said:-

"it is essential that the outside gears should be of sufficiently rigid construction and provided with adequate bearing surfaces for the additional duty they have to perform. Furthermore, it is of the utmost importance that the fit of all pins should be to close limits. With the conjugated gear the effect of clearance on each of the six pin joints is cumulative and any clearance in the fixed fulcrum of the "2 to 1" lever and the floating fulcrum of the "equal" lever is multiplied by three and by two respectively at the centre valve. Unit clearance at each of these eight points would consequently be multiplied by eleven at the centre valve. The cumulative effect of unit clearance at the seven, pin joints of each outside Wa1schaert valve gear is only approximately 3½ units, but the total amount of any such lost motion in the two outside gears will also be transmitted by the conjugated gear to the centre valve. It will be clear, therefore, that on both the primary and the conjugated valve gears, bearings of ample proportions manufactured to close tolerances are essential to successful performance; the most vital points being the fulcrums of the "2 to 1" and "equal" levers. In an endeavour to minimise the effect of wear, roller bearings were given an extensive trial but were not found satisfactory on those portions of the valve gear which had small angular movement."

(Spencer had worked out the Pacific valve gear for Gresley so knew exactly what he was talking about, and i think it fair to say was one of very few people who understood the gear in detail, Gresley and Holcroft being the 2 others).

my conclusion is that Cox put in the report what Spencer told him at the time, which occurred before Thompson sidelined Spencer. i doubt however that Thompson told Spencer what the purpose of the report was for. this is pure speculation on my part, and there may be other reasons why they both used almost the same words. i know a little about Stuart Cox as a great friend of mine corresponded with Cox when in retirement in Devon, and i dont think that Cox really understood the finer points of the conjugated gear.

cheers,
julian

 

Whilst I am grateful for the pointer to Bert Spencer, is it really helpful to make such supposition where there is no evidence to suggest any link at all between Spencer, Cox and Thompson with the report?

To me that smacks of trying to find some way of blaming Thompson further to suit a bias.

And again - Cox apparently is now deemed not worthy to pass judgement on the conjugated valve gear as an outside observer. Despite being an engineer in his own right, working alongside someone who was arguably one of Britain's finest CMEs.

This quotation sums up how I feel about yours I am afraid Julian. Sorry.

 

Be pretty astonishing if Cox hadn't used Spencer as a source of information really. Isn't the primary purpose of external consultants to tell the executives what they won't believe when their own staff tell them?

 

Note the main difference though. The leading bogie of the Nord Pacific is conventionally placed, not pushed forward as on the A2.

 

It's probably been covered but how did the Thompson locos compare to the Gresley or older equivalents in terms of staff comfort and man hours and difficulty for preparation and disposal?

 

But if Julian posted supporting ET no doubt you'd agree with him. "Believing what we want to believe" is not the sole prerogative of only one side of this debate.

 

In this particular case however, either Nock was told what he wrote by someone else, or he was told the truth and lied about it. Those are the only two options and what his general tone has been over the books you have read is not relevant. So are you saying he lied?

dealt with earlier

Plenty of unecessary vitriol, how much is with little basis in fact is another question. At this late stage in the history, getting wound up is pointless.

It might be, but then so many of the accounts are consistent with each other. Either there was a huge conspiracy, including people well outside the LNER, or the bulk of the "evidence" is trending in the right direction.

There probably is, but I've been reading this thread for three years now, and I'm still unconvinced that the bulk of the evidence is wrong. Even the famous report hasn't shaken my belief - as I mentioned up thread, the lack of context and restricted investigation make a nonsense of the conclusions, however damning they may be.

I thought I explained most of it fairly concisely, with the exception of the question of others abandoning conjugated gear, which I have enlarged upon since. What would you like me to explain further?

What about the past? Stanier and Cox should have known and should have taken into account what had happened before the war, when good maintenance meant that the gear did not wear as rapidly as it did once wartime maintenance began to take effect. Without that information any statement as to the value of the gear, the future rates of wear and overhaul costs becomes nonsense, unless a qualification is added to the effect that the conclusions relate purely to the exisiting wartime conditions. No such qualification was provided. Further, there was no attempt to investigate the reasons for the wear with a view to reducing it - that had to wait until the end of the war! Incredible. And then you wonder why I think the report was biased!

 

I think there is a clear difference between someone presenting some evidence with quotations, and that Julian has posted previously. I have on several occasions agreed with points made on this thread - most notably whether the P2s should have been rebuilt - yet I get the brunt of aggression and accusations of bias when unsubstantiated (or at the very least, not evidenced) claims are put forward. I always try to quote sources in comparison.

You spend an awful lot of time aiming the finger at me and yet I note you and Julian have done much of the "believing what we want to believe" - any potential criticism of Gresley being met with accusations of "ridiculing" of course, for which I note you have not deigned to respond to my previous post. Perhaps some truths are more painful to respond to than others?

 

They are in almost identical positions - are we looking at the same locomotives I wonder? Thompson's is certainly slightly further forward but there is no way the Chapelon cylinder position could be described as being "conventionally placed" if we are being so insular as to suggest UK practice was the norm.

 

You raise an interesting point but I think one would first have to work out how many three cylinder locos there were outside of the UK and what valve gear they used, to draw any global conclusions. My sense is not that there were not that many three cylinder locos (excluding compounds). There were some in the US, Thailand, China and Australia to my knowledge, many of which had Gresley gear (plus Tom's NZ example). I don't think (I am guessing in the case of the US) any of these were built after 1940 although three cylinder locos had also probably largely gone out of fashion by then to the extent they were ever in fashion. The Australian D58 (1950) use something described as a "rack and pinion gear" whatever that might have been, because of concerns with the Gresley gear on the D57s but that was less successful. VR Heavy Harry (1941) had a unique (as far as I am aware) conjugated gear which combined the motion of a couple of parallel transverse shafts driven from each outside valve, according to Oberg, chosen because of dislike of the Gresley gear on the S Class pacifics. (Pic attached of a rather good model of H220). The three cylinder Baldwins in Thailand were apparently generally considered poor locos but I don't think that was laid at the door of the valve gear. I think the Hanomag pacifics which came after had three sets of valve gear.

And in response to another post, I am not sure I would call all Gresley gears elegant - have a look at the large rocking beam on D5711 at Thirlmere.

Personal view is I don't think one can say Gresley was wrong any more than Chapelon was wrong with pursuing compounding when the rest of the world had given up. Equally, there is evidence that railways which had or inherited Gresley geared locos were not inclined to persist with it.

 

If you meant my post, I'm more thinking of the elegance of the idea, rather than the item itself. That said, Gresley gear is just a little less massive than that....and it's hidden