P2 Locomotive Company and related matters

The more I look at Thompsons Pacific's the more I like them.

 

Over here please ............... https://www.national-preservation.c...lysis-2012-present.35938/page-74#post-1635369

 

Congratulations on being able to post a link old boy.

 

My pleasure. Fill yer boots.

 

I'd prefer the discussion to go over there. Any genuinely new points on that subject always welcome.

RE the P2 the P2 Trust is ably building - no, the DP2LT isn't sharing any development with the P2 Trust. As I understand it (correct me if I am wrong) a reasonable request for a sharing of funds towards development was the stumbling block.

 

That sounds very likely - I did expect something like that to happen at some point, I'm afraid.

 

Difficult to share what you don't have...

 

No,not a destreamlined A4. Different wheel spacing, different frame and cylinder layout, different valve gear and most of all divided drive. As to being referred to as a "post war A4" it can certainly be seen as Thompson's replacement for the A4 as the premier express loco, but not a development of the design. In terms of layout it would be more accurate to say it's a development of the A2/2. RCTS locomotives of the LNER vol 2A shows a number of proposed layouts including several for an A1 class after the A1/1. They date from January 1946 to September 1946. Some were semistreamlined( those dated prior to Thompson's retirement), but all except the first had the more normal bogie location just ahead of the driving wheels. They did retain the divided drive but gave up on the equal length connecting rods.

 

Identical from the front drivers backwards.

From the front drivers forward, yes. Identical to A4 layout rearwards.

Absolutely agreed.

It uses most of the same standard parts and was intended to be streamlined and shares many aspects of its design development. How it could not be seen as a development if the A4 is beyond me because that was the intention clearly.

In terms of the front end perhaps but it definitely was meant to be a development of the A10s and A4s. New builds and rebuilds of A10s were intended.

Yes that one has always given me pause for thought. Not retaining equal connecting rods, 4470 could have had in theory three separate sets of drivers and the normal wheel spacing. No idea why it went like that.

 

I think we will have to disagree on that. Thompson wanted to design his own locos, not just improve the Gresley design. He had already produced his A2/2 and A2/1, and the A1/1 was the express version of those. Just using bits available off the shelf doesn't make a design a development of whatever used those parts before.

 

If you want to see a true development of the Gresley Pacific concept look at Porta's proposal to the A1 Trust. But, there again, going back to the W1 original concept (with Gresley trusting his instincts rather than listening to Professor Daley) would have proved the best way forward. If you are chasing high power and efficiency there is no excuse for not reducing unexpanded losses.
The Super A4 design did aim for a 275 psi workings pressure with a 50 sq ft grate area. This is interesting since 20 bar/300psi was pretty well standardised by the time this proposal came about. The LNE was aiming for zero hardness water supply, so the B.P. conservatism is hard to understand. If 20 bar had been taken as the design working pressure this would open the door to the continuation of the compound development. It is a pity that the water tube boiler was viewed as problematic. The history of the original W1 boiler is intriguing. The records show that it gave little in the way of trouble. In spite of the criticism levelled at it it allowed the output of some 1700 or so ihp. A pretty fair match for what was expected of the original A1. And this was all that was expected of the original, this was the aim of the design. Within the U.K. loading gauge you are very restricted. Outside cylinder internal diameter is a problem. You cannot build as high as you would like to either. Back in the 1930s and 40s it hadn't been fully realised, certainly not in the UK, how improvements in steam circuit and motion design would permit the utilisation of smaller driving wheels. So, what could you adjust to obtain more power? Cylinder numbers and boiler pressure. There is more but this is what was largely understood at the time.

So elsewhere in the world both thermodynamic improvements and mechanical design improvements had progressed enormously. Here in the "home of railways" did we keep pace? Could we see any need? Did we even care?

 

Deleted

 

For those of you who would like to know more about the P2 project or have burning questions for the engineering team, why not attend one of the presentations being given along the route of the ECML in the coming months?

"The A1 Steam Locomotive Trust has announced that it will be holding a number of presentations on the project to build new Gresley class P2 No. 2007 Prince of Wales along the route of the East Coast Main Line from London to Edinburgh and all the way to Aberdeen during 2017.

The class P2 2-8-2 ‘Mikado’ locomotives were the most powerful passenger steam locomotives to operate in the UK, designed by Sir Nigel Gresley to haul 600 ton trains on the arduous Edinburgh to Aberdeen route. Sadly, the design was never fully developed and they were rebuilt in 1943/44 and scrapped by 1961. The A1 Steam Locomotive Trust (registered charity and builders of famous new steam locomotive No. 60163 Tornado) is building the seventh member of this class over seven years at an estimated cost of £5m. The project will demonstrate how the design can be fully realised through use of modern computer design techniques, enabling the new locomotive to deliver its full potential hauling passenger trains at high speed across today’s national network.

The first Roadshow is at The London Transport Museum, where all attendees will receive complimentary access to the Museum Galleries on the day. Each presentation will feature key Trust personnel including Mark Allatt (Chairman) and David Elliott (Director of Engineering) and will cover the background to the project, progress to-date, future plans and details of how to get involved. The presentations will run from 11:00hrs to 13:00hrs on each of the days listed below and are open to existing supporters and interested members of the public:

• Saturday 14th January 2017 – The London Transport Museum, London
• Saturday 18th February 2017 – The Great Northern Hotel, Peterborough
• Saturday 18th March 2017 – Doncaster Museum & Art Gallery, Doncaster
• Saturday 22nd April 2017 – York Railway Institute, York
• Saturday 13th May 2017 – Darlington Locomotive Works, Darlington
• Saturday 17th June 2017 – Newcastle Mining Institute, Newcastle
• Saturday 1st July 2017 – Edinburgh Jury’s Inn, Edinburgh
• Saturday 14th October 2017 – Dundee Heritage Trust Discovery Point, Dundee
• Saturday 25th November 2017 – Aberdeen Jury’s Inn, Aberdeen."

Foxy

 

....meanwhile, in a shed in Darlington.... https://twitter.com/TomIngall/status/823481879726817280?s=04


Foxy

 

Is this for the next series of the reassembled? 'James will reassemble a Gresley 2-8-2 Mikado'

 

You'd have to be able to to dismantle it first! However, I believe he is making the 'slacking cock flange'!

Foxy

 

Given his day job, he certainly looks right at home standing next to a large tool...

Tom

 

Tom Ingall reports on today's visit:
http://www.bbc.co.uk/iplayer/episode/b08bbkmk/look-north-yorkshire-lunchtime-news-23012017
Start watching from 5.20 onwards.

Foxy

 

Think he's been green with envy of since Clarkson did the Top Gear footplate trip instead of him and he's lining up for his turn...
Q. If Tornado had been allowed to do 90mph would it have beaten the Jag ? ( in reality it was probably the Path rather than the Train determined the speed / time...)

 

What shade of Green though?!