Talk:SR Leader class

Good article review

I've reviewed the article, I believe the concerns from the previous review have been addressed with a number of good secondary sources now used and correct PD tags added to the relevant images. Thus, I'm happy to make the article a good article. The Rambling Man 12:35, 14 July 2007 (UTC)

Priming

Hello! I have changed the wikilink to priming, which is a dab page, in the "Cylinder design" section so that it links to [[Priming (steam engine)]] instead. Note that this is a redlink. I didn't want to leave the link to the dab page, but there are no suitable targets on the dab page, and I suspected that this topic might be worth its own article. If not, please remove the link entirely. Thanks. --Tkynerd 04:25, 9 September 2007 (UTC)

Not an expert in the field, however I do know for a fact that priming has nothing to do with cylinder design, but may be traced to water carry-over from the boiler. It is mainly linked to impurities in the water making it foam up, fill the steam space and get drawn down the the steam collector pipe. Bulleid was the only British locomotive engineer to address the problem of water quality, adopting the French TIA (Traitement Intégral Armand) on-board water treatment system, doing so with great success so I am surprised that the subject of priming should come up in article on his work. However the man who really solved the whole problem, including priming, was L.D. Porta in the 1970s in Argentina. Boiler Water quality and treatment method is a huge subject, certainly worth its own article. In the meantime, I suggest you follow these links: [1]; [2]--John of Paris 17:40, 15 September 2007 (UTC)

Well, to be honest, all I was really interested in was getting the dab link fixed so it points to an appropriate target. I could have simply removed the wikilink, but in this case I decided there was a possibility that the subject might deserve its own article. The further research and any changes should be carried out by someone directly concerned with this article. Just, please, don't restore the link to Priming without a dab! :-) --Tkynerd 01:06, 16 September 2007 (UTC)

When I wrote the above comment, it hadn't hit me yet that when I'd looked at the "Cylinder design" section again, the link was no longer a redlink. User:Bulleid Pacific has created Priming (steam engine). Excellent, thanks! --Tkynerd 01:09, 16 September 2007 (UTC)

Going on from my comments above, what is being described in the new article is not generally called "priming" and probably involves greater quantities of water. Of course it also involves water-throwing from the chimney, but that is avoided by opening the drain cocks and with piston valves this is a must, otherwise you run the risk blowing off the cylinder covers. With slide valves the danger is less as they will lift off their faces; even so, I would imagine that repeatedly allowing that to happen would not do the exhaust edges much good. What I think Bulleid was hoping to lessen with his valve design would have been condensation due to pressure drop resulting from expansion in the cylinders and the cooling of the steam as a result of giving up heat due to work? The condensation would take the form of droplets in suspension - or wet steam. This would not lead to priming, but to loss of efficiency. It could be counteracted by high superheat giving a greater temperature gradient and/or in some cases by steam jackets that kept the cylinders hot. Bulleid was obviously hoping for a jacket effect from the encircling sleeve valves, however, I suspect it could be shown that such would not have been the case — but that's another story.--John of Paris 11:30, 17 September 2007 (UTC)

R.G. Jarvis??

Just one more thing. Surely it is not correct to count R.C Jarvis as one of the designers of this locomotive. He had nothing to to with the design. He simply concluded after tests that it would have needed a complete redesign to have any success.--John of Paris 17:51, 15 September 2007 (UTC)

Interchangeable bogies?

Just think about it. Any bogie is by definition an interchangeable component. It would be hard to make it otherwise. So I don't see how it could have been "at Bulleid's insistence". He probably recommended keeping a pool of extra bogies in order to save time off the road. That would seem logical. But to say that it proved an "ineffective measure" is patently absurd, as there was never an opportunity to put it into effect! Five locomotives were being built, only one of which actually ran and that never reached full operating order.--John of Paris (talk) 18:41, 12 March 2008 (UTC)

Name

Just occurred to me; as the first working unit wasn't completed until after nationalisation, ought the title to be "BR Leader Class"? – iridescent 13:07, 15 April 2009 (UTC)

Well, it was designed under the Southern Railway, and has its pedigree within the Southern fleet of locomotives, so technically it is a Southern Railway locomotive; it's just that events overtook things a little. Otherwise, it would look odd amongst the BR 'Standard' classes, and would turn a few heads amongst the enthusiast fraternity to say the least! I realise that the SR N class and N1 class articles should technically be under SECR, but a bit of 'artistic licence' is required when naming the articles to satisfy the majority of people, as the bulk of these classes was built by the SR (these articles will probably be relocated at a later date, anyway). However, it is impossible to say whether BR would have started a Leader class had it not been sufficiently developed under Southern Railway ownership, and so I think it is safer to keep it as it is. --Bulleid Pacific (talk) 20:07, 16 April 2009 (UTC)

Ballast??

The "Operational details" section mentions "a raised floor covering ballast material.". Was this intended to link to (rock) Track ballast, or was the term "ballast" being used simply to describe "added weight" (similar to Sailing ballast)?. Wuhwuzdat (talk) 16:38, 21 April 2009 (UTC)

The latter. --Bulleid Pacific (talk) 22:24, 25 April 2009 (UTC)

Thermic syphon

"four thermic siphons from beneath the firebox to pre-heat water entering the boiler,"

This is not the function of a thermic syphon.

86.177.23.232 (talk) —Preceding undated comment added 22:24, 9 February 2010 (UTC).

TFA?

How about nominating this for TFA? It would be a lovely article for the main page, but obviously I thought I ought to ask the main contributors before nominating. I've written a little blurb below: Bob talk 20:09, 18 September 2010 (UTC)

A frame from the film, depicting the moment Holmes first encounters the burglar.

The SR Leader class was a class of experimental 0-6-6-0 articulated steam locomotive, produced to the design of the innovative engineer Oliver Bulleid. Intended as a replacement for the ageing fleet of M7 class, the Leader was an attempt to extend the life of steam traction on the Southern Railway by eliminating many of the operational drawbacks associated with existing steam locomotives. Design work began in 1946, and development continued after the nationalisation of the railways in 1948, under the auspices of British Railways. The Leader project was part of Bulleid's desire to modernise the steam locomotive based on experience gained with the Southern Railway's fleet of electric stock. The design incorporated many novel features, such as the use of thermic siphons, bogies, and cabs at either end of the locomotive, resulting in its unique appearance. Several of its innovations proved to be unsuccessful however, partly accounting for the project's cancellation in the early 1950s. Five Leader locomotives were begun, although only one was completed. Problems with the design, indifferent reports on performance, and political pressure surrounding spiraling development costs, led to all locomotives of the class being scrapped by 1951.(more...)

0-6-6-0 or 0-6-6-0T

The article describes the locomotive as an 0-6-6-0, but surely 0-6-6-0T is correct. The article also mentions "the tender". AFAIK, the Leader class did not have a tender, which is why 0-6-6-0T is correct. As this is a FA, I won't be bold, but am putting this up for discussion first. Mjroots (talk) 05:59, 22 September 2010 (UTC)

No tender indeed; and since the entire water supply was carried on the locomotive main frames, it's a tank engine. --Redrose64 (talk) 18:58, 22 September 2010 (UTC)

Article suitable amended and corrected. Mjroots (talk) 19:52, 22 September 2010 (UTC)

Operational assessment

The culmination of the project was a £178,865 5s 0d (£4,074,550.40 in today's money, converted at the 1950 rate) bill for the taxpayer, though when the press reported the story as late as 1953, £500,000 (£11,390,000.00) was claimed to have been "wasted" on the project. R. G. Jarvis, who was placed in charge of the project after Bulleid's departure, insisted that the locomotive required an entire re-design to solve the problems of the original concept.

Isn´t the word used more neutral? Maybe spended, just replace wasted.

eg £500,000 (£11,390,000.00) was claimed to have been used/spended on the project.

Olof nord (talk) 16:01, 22 September 2010 (UTC)

The paragraph in question neutrally says what the total bill was, and then goes on to discuss the press reaction, which was that money spent on the project had been wasted. In the sense in which this article uses it, the non-neutral language is correct. – iridescent 20:03, 22 September 2010 (UTC)

How approximately is "approx."?

Tractive effort is given as "30,000 lbf (Approx.) (133.44 kN)". But if the 30,000 lbf is only approximate, what is the justification for stating the metric conversion to the nearest 0.01 kN? Is that the level of accuracy implied by "Approx."? If the original figure could be several hundred, or even thousand, lbf off then the level of accuracy in the conversion looks excessive. Even if the original figure is plus or minus a few lbf, then (if my math serves me correctly) the error would be around plus or minus a few tens of Newtons, so 0.01 kN accuracy is still pushing it? TheGrappler (talk) 21:23, 22 September 2010 (UTC)

It is listed as approximate due to the fact that there are few records, far less any that indicate the maximum potential of the locomotive. UPDATE: Have revisited the HAV Bulleid source, which includes a general layout diagram and the actual TE of the design, which is 26,300lbf. I have revised the article to reflect this. --Bulleid Pacific (talk) 14:31, 12 January 2011 (UTC)

Importance of nationality?

Am I the only reader who looked at the lead paragraph & would have been happier if it had explicitly stated this was a British make of locomotive? Maybe I'm displaying an unconscious US-centralism here, but until I saw the reference to Southern Railways I presumed that this was a US-made class of locomotives -- although a 0-6-6-0 locomotive would have been considered very experimental in the US. Obviously, if others agree with me, a lot of articles would need to be altered to add a qualifier (e.g., "manufactured in the US", "manufactured in the UK", etc.), but it would help those of us who aren't railroad nerds. -- llywrch (talk) 21:58, 22 September 2010 (UTC)

The second sentence of the article is "The Leader was an attempt to extend the life of steam traction on Britain's railways", which ought to be a hint. I'd be inclined not to include a "made in the UK" because of the precedent it would set; this was an experimental design which didn't go into production, but a lot of successful designs ended up being manufactured worldwide. – iridescent

Erm. I didn't see any indication of nationality in the teaser on the Front Page, so my eyes missed that when I went to confirm this in the article. And even had it not been there, it's not a point I would have pushed for, rather remind everyone that many readers assume that, unless explicitly told otherwise, a given subject applies to their own country. One of the goals, I hope, of writing articles for the general reader. -- llywrch (talk) 16:11, 23 September 2010 (UTC)

Well, the blurb may have been better if it had said "a British locomotive", although it would have made the first sentence very busy. Only slightly lower down in the TFA blurb says "British Railways", so anyone reading beyond the first line wouldn't be confused. I'm not quite sure what you mean by the word "make" - unlike a car, steam locos were usually made by an in-house design and engineering works, in this case Southern Railways. Bob talk 17:13, 23 September 2010 (UTC)

The proposed teaser is in the TFA? section above. The actual teaser used is filed at Wikipedia:Today's featured article/September 22, 2010. In both cases, I see that the first indication of nationality is in the third sentence, which concludes "under the auspices of British Railways." I don't think that's too late. --Redrose64 (talk) 12:56, 24 September 2010 (UTC)

Designed use

"It was intended as a replacement for the ageing fleet of M7 class tank engines still in operation on the Southern Railway" Somewhat hard to believe - it seems incredibly oversized for that purpose, unless the M7s were regularly double- or even triple-headed, of which I can find no mention in their article. Marked with "citation needed".--No qwach macken (talk) 14:43, 10 June 2012 (UTC)

Michael Bonavia, History of the Southern Railway 1987, p.156 says:

The Traffic Department after the war needed a general-purpose engine of medium power, particularly as the veteran M7 0-4-4T engines were becoming life-expired. Bullied conceived a machine that would unite the virtues of steam and diesel traction ...' Bullied was known for 'over-engineering' as was the case with the WC/BB class. --Das48 (talk) 15:07, 11 June 2012 (UTC)

The statement is made twice in this article: once in the lead section, and once under Background. Any fact mentioned in both lead section and in the main body only needs to be referenced once: in the main body. In this case it was so referencd, but I've added a link to that ref into the lead. --Redrose64 (talk) 18:23, 11 June 2012 (UTC)

Sleeve oscillation

< This included oscillating gear that gave a 25-degree axial movement >

Rotary movement, I think. The axial movement was provided by the valve gear. — Preceding unsigned comment added by 86.183.83.192 (talk) 14:14, 29 August 2012 (UTC)

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