34039 Boscastle WC class

Tom is undoubtable correct in saying that Bulleid pacifics didn't actually go through carriage washers, however, several writers did quote this as a reason given for their shaped casing......
DW Winkworth P20 (Bulleid's Pacifics) "The whole of the engine from the wheels up was swathed in a casing, independent of the boiler, described by the designer as "air-smoothing", to allow cleaning through carriage washing plants. Flat at the top, it even had a pivoted cover to slide over the chimney!"
B Haresnape P19 (Bulleid Locomotives) "With a most unorthodox appearance, described as air-smoothed. (and intended to allow cleaning through carriage washing plants).
RJ Mannion P55 (The Southern Pacifics) believes that although often repeated, the idea of passage through carriage cleaning plant was not the real reason. He believes that the casing was originally designed as "streamlined" as per LNER and LMS. This would have appealed to the publicity conscious Southern Railway board. However with the advent of WW2 such frivolity was replaced by the "Air-smoothed" easier to keep clean (- possibly in existing carriage washers...) mixed traffic engines. He was also dismissive of the chimney cover being used in sheds as it may well be forgotten and left in place.... but he thought that it was a feature only early on and it was discontinued after smoke box modifications ( cowled front?).
C Boocock P 51,52 (Oliver Bulleid's Locomotive) believes air-smoothed was to convince publicity people that it was streamlined when it was not. However "What the all-over , air-smoothed casing on a Merchant Navy did do was to enable the designer to eliminate yet more metal structures such as side footplates and valences and the brackets to hold them.....the overall casing was shaped to fit the outline of the wide firebox..."
It would seem that there were several reasons that could have been influencing the shape of the boiler casing.....as with many engineering situations.

 

What I would like to see is any primary evidence that the shape was chosen specifically to enable driving through carriages washing plants. (An example would be - was there ever a plan to site such equipment at the major motive power depots? Not that I am aware of. Driving a loco from Nine Elms to Clapham Junction just to save time on cleaning by using the carriage washer there is hardly conducive of making an efficiency saving).

As I mentioned, the SR did have portable pressure washers that by the War were certainly used for both carriage and locomotive cleaning. The slab-sided profile would make use of such equipment easier. So my gut feeling is that somewhere something is lost in translation, and e.g. a design made to make cleaning easier with "carriage washing equipment" has morphed in time to make cleaning easier with "carriage washing plant", until you arrive at a situation where the design rationale has become accepted fact.

Also worth mentioning: it is often cited in support of the theory that the Bulleid tenders have the same profile as his carriages. Which I think is true, but so to do the side tanks on a Riddles 80xxx tank - it was just a bit of Brighton Drawing Office artistry!

Finally, I'd reference this:



The fact that multiple secondary sources all repeat the same claim does not make it correct - even less so if they all cite each other in support!

Tom

 

Like others, I've seen references to flat-tops and carriage washers. I seem to recall HAVB (about as close to the source as anyone outside the Southern Railway could be, if somewhat less than objective betimes!) mentioning the matter as a a consideration.

That Bulleid, like his brother-in-law Ivatt, designed with an eye to the realities of the available resources, including labour, in mind seems unquestionable. Whether he had access to a see-saw as a child, less so (*).

For verification of specific design objectives and mythbusting, I guess we'll have to await the in depth interrogation of surviving SR documentation (and likely that of the wartime Railways Executive Committee) in @S.A.C. Martin's eagerly anticipated opus.

* Yes .... that was an oblique reference to his last standard gauge design.

 

I think the carriage washing idea is yet another example of secondary evidence being repeated ad nauseum for decades without any primary evidence from the usual sources (eg the engineering and PR departments) you would expect to declare this “advantage” to all and sundry.

Much like a certain CMEs reputation, stuff like this does railway history no favours and adds to it not being taken as seriously.

I personally don’t believe there is any truth in it whatsoever - but I am at the start of my research on my Bulleid book - if I find anything I will of course revise my opinion.

 

Reading the comments about the casing I find it baffling how there could not be a definitive answer as to what purpose it serves. When the locomotives were first introduced, was a reason not proffered in some form of a press release? Surely questions were asked?!! It’s not like they stood out from the crowd.

 

I'd be interested in reading said book. There's likely some truth in what you've posted here; having looked at some of the drawings of the original Merchant Navy casing for 35011 (apologies for thread drift), some of the drawings of the casing refer to their parts as streamlined or streamlining, few refer to it as air-smoothed, many just refer to it as casing. It might be a different story for the Light Pacifics due to the intervening 4 years, I've not spent much time studying their casings drawings

 

Could this be another mystery that was caused by the time of first introduction..in the middle of World War 2 .......when press releases about new steam locomotives might be believed to be giving information to the enemy?
But it is surprising that the designer (OVSB), did not appear to correct any erroneous theories. ( he was alive until 1970).

 

Have you ever seen the pipework below the cladding? The cladding could have been in the shape of an inverted U or as it is. I know which I prefer.

 

Std tank makes another good point and I seem to recall reading that an advantage of the "Air Smoothed" casing was that it could be lifted off in virtually one piece when in the works for maintenance. I believe there are pictures in workshops showing these large sections......which would presumably be primary evidence?

 

I think the definitive answer has likely been ignored in favour of the myth.

The air smoothed casing of the locomotive is not optimised for "carriage washing" - in any case, such washing could introduce a huge amount of detritus/ onto parts of the locomotive you wouldn't want it to (e.g. axleboxes/valve gear/cladding) which could damage components, particularly where axleboxes are concerned.

I remain sceptical: if this was such a big deal in the design phase, Bulleid would have said quite a lot about it in the press publicity. Not a word as far as I can see.

Yes, photography definitely counts as primary evidence, if it is paired with context.

 

Meanwhile there has been more work done on Boscastle's tender, with apologies for the poor pictures.

 

There are some more pictures posted on the Boscastle website which shows some other new tender fittings. It is good to see that the website is receiving much more regular updates.

 

Another update has been sent out to shareholders, outlining the work being done to complete the tender. I expect that this will be uploaded to the Boscastle website soon.

 

There are Boscastle "Shed Tours" this weekend at Loughborough engine shed. More details are available on the Boscastle website.

 

Reverting to the "air smooth casing" issue briefly, , didn't the early examples have the casing made from a compressed wood fibre board of some sort? I imagine this might have been a wartime metal-saving measure that was easier to achieve in flat sections than cylindrical mouldings - easier and quicker to fit, too.

 

[Edited to reflect correction in light of posts below]
IIRC, the production run of the first batch (21C3-10). Readily identifiable by a longitudinal strip about halfway down, running the length of the casing.

 

The MNs from 21c3-21c10 had light weight board (made from asbestos I believe) as a weight saving measure as they were slightly overweight. By the time the 2nd series MNs were built (21c11-20) this weight saving had been designed into the locomotive, so the sheet was metal again. I'm guessing the light pacifics had the same material as the 2nd series MNs, as they started rolling off the production line shortly after the 2nd series MNs.

 

Not quite correct: 21c1 & 2 didn't have it, nore did 11 onwards (11 was the first of the 2nd batch).

 

Cheers. OP amended accordingly.

 

No problem. The differences between the various shades of a MN is something I've been struggling through for nearly two years now with GSN. Everything tends to have between 3 and 5 different drawings for it, with often subtle differences between them.