Bulleid Pacifics - Past or Present

A Glut of Bulleids?

 

is Standard Bullys or XL'S. ?

 

I would class the rebuilds as " Standard Bully's " the originals as just bully's the Merchant Navies as XL bully's.

 

The Latest News page of the SLL website has been updated today, with news of all of our fleet, and up-coming events. https://www.southern-locomotives.co.uk/News/news.html

 

I'm also noticing short videos appearing on YouTube showing some work on various Bulleids including Sir Fred Pile at Sellinge. A thumbs up from me for these.

 

There have been several books written, over the years, which outline the various reasons behind the BR decision to rebuild all the MN class and half the WC/BB class. As we know several original Bulleid light pacifics still exist and have run many thousands of miles over the main line and on preserved railways. They do not seem to suffer from the failings outlined by BR. Is this because they are better maintained or have the "defects" been addressed in preservation?

 

Lower mileage at lower speeds
Crew that all care for them (some loco crew did, some didn't, but obviously, only the ones that did care stick around in preservation)
Keeping them cleaner
The book on Bulleid pacifics I'm reading at the moment says that BR cheaped on the oil for them.
Modern lubricants and chain technology advances.

I'd love to see one with the gear-driven valve-gear as originally planned. Ditto with less lightweight frames/a redesign to limit the flex forces on the oil bath.
Best win the Euro millions. Twice...

 

Most likely because they enjoy better maintenance in preservation, than when they were in service, things like oil bath seals are much better today, than what was available back then, and they do nothing like the sort of distances and, unless they are mainline approved engines, nor the speeds,

 

They had a lot of failings. Keeping the oil bath from leaking when the middle axle went through the middle of it was one. The bath was also welded to the frames, I’m not an engineer but surely with the flexing of the loco main frames would it not have been better by giving them a bit of flexibility but riveting and avoiding leakages at the joints? Bulleid also decided to design his own stem reverser that was temperamental to say the least ignoring the fact that all three constituent companies of the Southern had reliable steam reversers that he could have used. Preserved examples are obviously maintained better and not run at speed, with one exception, it would be interesting to hear how Tangmere stands up to more rigorous use.
Among loco crews they seem to be a bit Marmite, some loved them, no crawling around between the frames oiling up, while others never seemed to get the best out of them. I think it was the maintenance costs that helped to swing the argument in favour of rebuilding.
One thing that cannot be denied, the boilers were the best when it came to steaming capacity.

 

Does make me wonder, given that Johnb's precis is little different to what BR already new in the 1950's why the Bulleid boilers were not the starting point for the BR Standard Pacifics

 

Politics / not invented here syndrome?

Maybe it’s a mistake to imagine that the design process came from a single overarching mind, rather than essentially being design by committee. And committees always have elements of compromise, and also always get swayed by stronger voices. The Brighton mouse in the corner with an unpopular loco but a fabulous boiler may not have been properly listened to …

Tom

 

It interesting, as Riddles' avowed design idea was to make an engine that steamed well as a first priority.

OTOH, Bulleid's stock post-Leader can't have been high, and with the various issues with the pacifics, I can imagine everyone wondering what compromise/complexity was going to come out of the woodwork with the boilers in 5-10 years time.

The Stanier/GW boilers were a known quantity, so that might have swung it when laying down a 20-40 year design paradigm.

 

Suppose with the 'Duchess' boiler being a good performer you would take that as a start point as its the devil you know... plus whether the capacity for weld repairs was widespread.

 

Probably due to railway politics, Riddles, Cox and a lot of the design team were ex LMS men so it’s not surprising that a lot of the BR Standards were little more than updated LMS designs.
On the locomotive exchanges the MN in the hands of driver Alec Swain gave some sparkling performances but at the price of heavy coal consumption. I suppose the original Pacifics were seen as troublesome and were rejected on that basis alone.

 

Heavy coal consumption is not only a cost in itself but means harder work for the firemen and more ash to be cleared away later.
Judging by numerous videos, Tangmere does seem to produce significantly more smoke even than other Carnforth locos. However Clan Line doesn't ...

 

It’s a bit difficult to compare now as the quality of coal varies from not bad to awful. I’m fairly certain that in steam days Nine Elms was supplied from Bettshanger in Kent, I know Kent coal was hard and as I remember there were some huge lumps seen in the tenders. I’ve always thought that Tangmere sounds a bit off beat compare with how I remember the original Pacifics

 

Perhaps it is more surprising that the BR team designed a completely new boiler for the Clan (not as far as I am aware based on any earlier designs) rather than basing it on the existing Bulleid BB/WC boiler that came out well from the 1948 exchanges. Too heavy perhaps and in any case the steel firebox would have needed redesign in copper.

 

What was the purpose of the Clans? The main fault seems to have been they were underboilered, address that problem and you end up with a Britannia. Even more odd is that the second batch were destined for the Southern, a region not exactly short of Pacific power.

 

Were they underboilered?
There's more evidence they were used as class 7 and couldn't manage that.

I agree it's odd they went to the southern region.

 

The purpose may have been nothing deeper than "Our new Standard range ought to include a Class 6". The loco stock inherited from the Big 4 included lots of Class 5, 7 and 8 but not a lot of Class 6.