LNER P1 2-8-2

Hornby would

Well, apart from some being built by Southern Rly. workshops during WW2 what's with the LMS 8F's for example?...

":::Jerry::::" wrote

Nothing, but look at the (superdetailed) Hornby range and see if it's representative of the variety and type of locos which operated on the real railways?

How many 'Pacifics' do they produce, compared with freight locos and tank engines?

Do we all have railways dominated by big express locos? Mine certainly isn't, and apart from 8-coupled freight locos (8F and WD 'Austerity') I've nothing bigger than a Black 5 or a Standard 5, and smaller locos are the norm rather than the exception. I'm not talking about a small layout either, mine's in excess of 20' x 10' - but representative of a secondary main line which carries a preponderence of coal traffic and general freight.

John.

Well, there's always the "Terriers" for that. SR 12 "Ventnor" RTR £40.00 at Model Depot.

In message , John Turner writes

If a Super D were to be made, I'd buy one. I've certainly no intention of getting a Claughton, or anything else ex-LMS with the possible exception of a Coal Tank, but that's most unlikely to be made RTR also.

There is confusion being shown here between four different measures.

1. Power = Rate of doing work, essentially the product of the drawbar pull and the speed. Other things being equal the limitation on power is the ability of the boiler to supply steam, hence grate area, heating surface, degree of superheat all figure. Basically the bigger the boiler the higher the power.
2. Tractive effort = the potential drawbar pull calculated just calculated from steam pressure, cylinder diameter and stroke and wheel diameter. This is what increases by putting a 1/2 inch on the cylinder diameter or on the stroke or reducing wheel diameter. It takes no account of the available adhesion or the number of coupled axles.
3. Adhesive weight, weight on the coupled wheels, rule of thumb being that the tractive effort could not exceed 20% of this figure, so increasing it meant the engine would exert a higher proportion of its potential tractive effort before slipping. This being the benefit of the side tanks, so long as they were full.
4. Power classification, 7P, 8F etc. These were calculated by different formula depending on expected duties so for passenger engines it was largely on power from the boiler, for slow freights more on tractive effort.

ie

According to the formula which I've forgotten but which used to appear in the Ian Allan books it did. It was a function of boiler pressure, heating surface, cylinder dimensions and wheel diameter.

"David Biddulph" wrote:

The line has had only three sets of rolling stock in its lifetime. The original wooden stock used from the line's opening in 1898 lasted until replacement in 1940 by new electric multiple units, which were eventually classified as Class 487 in the TOPS system. This new stock lasted over 50 years until it was replaced by Class 482 units, which are virtually identical to the 1992 tube stock used on the Central Line. Since its introduction, the stock on the Waterloo & City has diverged sufficiently from that used on the Central Line through various modifications that the two are not interchangeable. Rather than the red, white and blue London Underground standard livery, Waterloo & City stock still carries the original blue British Rail Network SouthEast livery that it carried when introduced. There are still other traces of BR branding around the two stations, despite the line having been part of London Underground for ten years. In January 2003 the Waterloo & City was closed for over three weeks for safety checks due to a major derailment on the Central Line which required all 1992 stock trains to be modified. That same year, responsibility for the line's maintenance was given to the Metronet consortium under the terms of a Public?Private Partnership arrangement. In April 2006, the line is due to close for 5 months for total infrastructure upgrade. This will include modifying the current 1992 tube stock to be repainted into official London Underground livery, it is unsure as to whether they will go along with the new modification to the livery, with the blue strap cutting off early in order to be DDA compliant.

Given that Bulleid was such an innovator, it is surprising how obsolete the 1940 stock was, with the switchgear compartment behind the cab taking up valuable passenger space. On the London Underground this went out with the 1837 prototypes that led to the 1938 stock, having it mounted below the floor.

Well, when you do remember it you will find that only three of those four items are in the formula, heating surface is not. Nominal starting tractive effort is 0.85P*D*D*S/d Where P is boiler pressure in Pounds/square inch, D is cylinder diameter in inches, S is cylinder stroke in inches and d is driving wheel diameter in inches. Sometimes TE is given at 75% boiler pressure in which case change the 0.85 in the formula to 0.75 Take a Brittania as an example: Boiler pressure 250psi, cylinders 20 x 28, wheels 74 in. diameter Hence TE = 32,162 pounds.

See also or here if you have Java enabled

Keith

Underground

It might have something to do with day to day maintenance, IIRC all LU stock is maintained above ground, the W&C stock is kept underground until major shopping is required.

The message from Christopher A. Lee contains these words:

My recollection is that the Drains bore is smaller than any other tube line. Maybe technology was not advanced enough in Bulleid's time to fit this under floor?

My typo - 1937.

Then they would not be able to run the current trains, which are standard tube stock.

The technology was there, used by the 1938 tube stock.

Always thought the tinplate tube train made by Ever Ready( of torch and Battery fame) looked more like it was based on the Southern Waterloo and City stock than anything London Transport operated, despite the toy being released in Red livery .

There is still a picture of a set at

G.harman

Perhaps they were anticipating the integration of the Waterloo & City into the LT network - just 50 years ahead of their time!

Cheers, Steve

Hmm. The tendency was inherited by BR and foisted on many diesel designs too!

Francis K.

It was particularly the bearings on the Garratt AFAIR.

But there were also operational problems like the water columns being spaced for a pair of 3Fs or 4Fs, not the spacing between the Garratt's tanks.

"Christopher A. Lee" wrote

Wasn't the boiler not to Beyer-Peacock's liking too? Too small and of typical Midland Railway design - ideal for the 19th century? Certainly compared with some of the boilers fitted to some of Beyer-Peacock's exports the LMS effort looked pretty feeble.

John.

Yes, but that wasn't as critical.

The Garratt arrangement is ideal in some ways because it allows a short fat boiler and a large firebox because the frames aren't in the way, So you're right about the boiler.

According to Brian Haresnape's "Fowler Locomotives", apparently both Horwich and Derby made independent enquiries of Beyer-Peacock for a Garratt design. I quote: "Unlike the Horwich version, the design Beyer-Peacock produced for Derby (at Anderson's request, not Fowler's) was "Midlandised" in most respects except for the bolier and frames. All the detail work was to Derby specifications, with the result that short travel valve gear was used, with the same cylinder and motion arrangement as designed for the 1914 batch of SDJR 2-8-0s. Even worse, the axlebox bearing sizes were to the traditional Derby standards, quite inadequate for the new locomotives." Fowler was the new Chief Mechanical Engineer, while Anderson was the Motive Power Superintendent. The above quote from B Haresnape is credited, by him, to Volume 1 of "Locomotive Panorama" by E S Cox. Hope this may be of use to the deabte. David Costigan