Bulleid Pacifics - Past or Present

Also, I doubt an MN would have fit on a turntable if it was any longer?

 

Thank you. So appearances were deceptive.

Good point.

 

There was quite a lot of variation on Bulleid tenders: some of those fitted to the light pacifics were as small as 4500 gallons, and they went up to 6000 gallons on a Merchant Navy.

This is a a good reference: http://www.southern-locomotives.co.uk/Class_Details/Bulleid_Light_Pacific_Tenders.html

The Drummond double bogie tenders (as currently preserved on the T9) were mostly 4000 gallons, the Urie / Maunsell pattern ones (as currently preserved behind King Arthur and various S15s) were 5000 gallon, as Spamcan noted.

At least one of the early Drummond tenders did have water pick up gear with a plan to install water troughs on the South Western mainline, but a suitable scheme couldn't be designed as there were not suitable flat areas at the right intervals. Thereafter, big LSWR / SR Locos had to have big tenders and non-stop distances became water-limited. The SR and BR (S) also ended up involved in a series of bewildering complex tender swaps when engines transferred sheds, since the N15s / S15s needed double bogie tenders on the Western section, but had to have six wheel tenders if the transferred to a central section shed on account of short turntables.

Tom

 

What the Bulleid tender lacks in length is more than made-up by its height, so they do carry similar amounts of water to the longer, but lower Urie/Maunsell tenders. This is personal conjecture, but presumably they were lengthened and mounted on bogies to assist with weight distribution on indifferent track, a problem that may have been resolved by the time Bulleid came on the scene.

 

There is no criticism implied in this question, but just wondering if anyone has an informed guesstimate of when the Gloucester & Warwickshire will have a MN hauling public passenger trains? Very excited about this!!

 

The society's members day is the 10th August and 35006 will be "loco in steam and as near working order as we can manage. ". That's all I know

 

Many thanks! Good to hear that.

 

I'd be blown away if it was in passenger service, but I could see that it could conceivably be chuffing up and down the yard by then, which is publicly viewable. Quite tempted to go along and see depending on my duties...

 

There is much discussion on the Royal Duchy thread about what went wrong yesterday, including mutterings about the steam reverser on an unrebuilt Bulleid causing difficulties for drivers. That was presumably one of several reasons for the rebuilding, but were those reversers always troublesome from the start or just prone to getting out of adjustment? It seems perverse to have incorporated the added complexity of a steam-driven contraption that is harder to use than a conventional mechanical reverser.

 

A well-functioning power reverser (note the qualifier!) is potentially a good thing in terms of reducing the workload on the crew, relative to a screw reverse. That said, the Eastleigh pattern reverser as fitted to the Bulleids was not well-functioning ...

It's always been a bit of a mystery to me about why Bulleid chose the Eastleigh pattern reverser, when he had available the Ashford pattern that had worked efficiently on many classes of loco for many years. The only thing I wonder is whether it was for packaging reasons, i.e. the Eastleigh reverser fitted more easily in the space available than the Ashford one.

There's an illustration here which shows how the Eastleigh reverser fitted between the frames: http://www.bulleidsociety.org/21C123/Pictures/Valve_Gear/valve_gear_ill.gif

By contrast, all the installations I've seen of the Ashford reverser show it oriented vertically, so it is possible that there simply wasn't space to fit an Ashford pattern one.

When it became apparent that the reverser didn't work well (but before the Jarvis rebuilds), there were attempts to redesign the reversing mechanism, but a satisfactory arrangement could not be worked out. The Jarvis rebuilds, of course, were effectively starting with an almost clean slate in terms of the arrangement of the valve gear, and presumably in that circumstance it proved more amenable to arrange a conventional screw reverse.

Tom

 

I suppose one factor may be that the screw reverse fitted to the Bulleid rebuilds isn't that conventional by 1941 standards. I believe that particular layout (reversing screw close to the gear, with a rotating shaft from the cab driving it) first appeared on (4)6256 in 1947, well after the Bulleid Pacifics were designed. Might have been possible to use that arrangement even on the originals.

I always assumed the steam reverse was Bulleid trying the save the crews labour and slightly missing the mark, or adopting American practice (like the power operated firedoors). Thing is, the power reversers on most US locos are more sophisticated than either the Ashford or Eastleigh designs; they're servo arrangements where the driver sets the desired cut-off and the reverser moves the gear to it, with no locking cylinder, which is why some US cabs look like they have a very small lever reverser (especially for the size of engine). Although they were apparently prone to hunting about the desired set point when worn out, when functioning properly it's a much better arrangement. Compressed air is a better working medium for servo applications than steam, but Beyer Peacock made a modified version with a locking cylinder work on vacuum-braked South African Garratts (where conventional steam reversers would be difficult to keep matched between engine units).

Edit: part of the above is rubbish. Pretty sure the GMA class had one big steam reverser, no synchronisation required. It was still a Beyer Peacock Hadfield design.

 

Fascinating (to me anyway) post on the SEMG forum which relates to Bulleid survival:

I guess unless you are familiar with the industry in question these sorts of subtleties don't occur to you...

 

that is a facinating story, so had it not been for the wagon scrap deals, its highly unlikely that any Bulleids would have been sold to preservation, if he had to meet a certain target of scrap to export. i should have imagined they would have been near the front of the queue as to which were easiest to cut , would i be right in thinking it was the wagons that woodhams were able to cut up ,with far less trouble and time that saved the engines?

 

That has certainly been reported many times over the years

 

Their survival might also have been due to the fact that the deal had been wound-up in the late 1970s, as he didn't exactly lay into his stock of locomotives when the wagons started drying up. He probably found it more lucrative to sell them to preservationists at that stage.

As for the reverser issue, for the first few years of operation, 34067 was pretty faultless in the reverser department. Will have to have a read of the Duchy thread to see what went on.

 

Shenanigans, it seems ...

Tom

 

67 year old locomotive has a fault - Shock!

 

Tangmere, the drama engine that causes the wrong kind of drama.

Cheers

 

Does anyone else think Tangmere seems to be a cursed engine or something? I swear the only time I've ever heard about this engine is when it's had another breakdown, or more recently threatened our entire movement!

Pity really, I wouldn't surprised if there's people out there avoid it or hear of taking part in a tour with dread...

 

Tangers has put in some superb performances over the years. She nearly turned Mr Riley's head when he had care of her! Not wishing to blow my own trumpet too loudly, but you can see several examples on my YouTube channel, beginning with this one:

However, she does seem to have attracted bad luck in recent years. Whether that co-incided with her change of ownership, Matty, I couldn't possibly comment. ;-)