If you register, you can do a lot more. And become an active part of our growing community. You'll have access to hidden forums, and enjoy the ability of replying and starting conversations.

A Webberized Mikado

Discussion in 'Steam Traction' started by Hermod, Feb 7, 2018.

  1. Hermod

    Hermod Member

    Joined:
    May 6, 2017
    Messages:
    365
    Likes Received:
    74
    Gender:
    Male
    Location:
    Klitmoeller,Denmark
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Mr Webb built a simple 0-8-0 locomotive having 240 litre cylinder volume and a three cylinder compound with 320 litre.The compound was better and more were built and hauled coal for many years.
    The first P2 with 220 psi had 445 litre and a 250 psi version can thus have 395 litre for same tractive effort.
    A Webberized version shall thus have 33% more that is 525 litre.
    If we allow GWR strokes of 30 inch we shall have two external high-pressure cylinders of 15 inch diameter and a single inside of 30 inch.
    Two 15 inch cylinders can evidently be further apart than the 21 inch cylinders of the first P2 for a given loading gauge.
    It will also allow plus-minus one inch horizontal movement of first coupled axle giving less track stress.
     
    pete2hogs and andrewshimmin like this.
  2. Hermod

    Hermod Member

    Joined:
    May 6, 2017
    Messages:
    365
    Likes Received:
    74
    Gender:
    Male
    Location:
    Klitmoeller,Denmark
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Mr Eigthpot has kindly shown a drawing of the original P2 cylinder and asked for a comparison to a Webb version with 50 mm flexibility of first coupled axle.

    LNER mainline gauge must have been wider than 8 feet 8 and the prince of Wales P2 will have smaller cylinders to clear present gauge.
    The outside LNER cylinder-center was 1022mm away from centerplane and I doubt that the P2 no 7 can be closer.
    The Webb version can have an 15 inch cylinder 1050mm away and still clear present loading gauge as shown .
     
    Last edited: Feb 27, 2018
  3. 30854

    30854 Part of the furniture

    Joined:
    Mar 8, 2017
    Messages:
    3,013
    Likes Received:
    2,949
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Brighton&Hove
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Mmmm..... Am I the only one thinking "high centre of gravity"? It's an issue which bedevilled more than one design. Just on the "Brighton", the B4x and D1x rebuilds come to mind.
     
  4. Hermod

    Hermod Member

    Joined:
    May 6, 2017
    Messages:
    365
    Likes Received:
    74
    Gender:
    Male
    Location:
    Klitmoeller,Denmark
    Heritage Railway Volunteer:
    No I do not currently volunteer
    P2WebbonGressley.JPG A picture of Gressley and Webb- like cylinder P2 and smokebox within a loading gauge with 8 feet eight platform edge distance
     
    Last edited: Feb 27, 2018
  5. Hermod

    Hermod Member

    Joined:
    May 6, 2017
    Messages:
    365
    Likes Received:
    74
    Gender:
    Male
    Location:
    Klitmoeller,Denmark
    Heritage Railway Volunteer:
    No I do not currently volunteer
    The first six P2s were rebuilt rebuilt to A2/2 pacifics.Done differently a more economic von Borries Compound respecting shrinking British loading gauges could have been made.



    gresley p2-thompson -von borries a22.jpg


    The outside 600mm high- pressure cylinder is 950 mm from centerplane and drives on to first coupled axle inside the coupling rod.


    Thompson A2 forhjul.jpg

    It could also have been made as Sauvage/Smith type three-cylinder compound and still be within gauge.Again the outside low pressure cylinders sit 1900 mm apart

    Most powerfull,economic British pacific and best-looking as well?
     
    Last edited: Feb 27, 2018
  6. 30854

    30854 Part of the furniture

    Joined:
    Mar 8, 2017
    Messages:
    3,013
    Likes Received:
    2,949
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Brighton&Hove
    Heritage Railway Volunteer:
    No I do not currently volunteer
    A VonBorries format compound would be lovely to see and to hear. I've always had a hankering for a B&NCR 'S' or 'S1' class 2-4-2t .... but they were 3'-0" gauge, so unless the Waterford and Suir Valley folks fancied one, probably not happening any time soon. :(

    Would a recreated 19th century VonB perhaps be a more likely newbuild candidate?
     
  7. Hermod

    Hermod Member

    Joined:
    May 6, 2017
    Messages:
    365
    Likes Received:
    74
    Gender:
    Male
    Location:
    Klitmoeller,Denmark
    Heritage Railway Volunteer:
    No I do not currently volunteer
  8. Jimc

    Jimc Part of the furniture

    Joined:
    Sep 8, 2005
    Messages:
    2,559
    Likes Received:
    1,702
    Occupation:
    computers
    Location:
    SE England
    Heritage Railway Volunteer:
    No I do not currently volunteer
    Both the GNR and GER loading gauges were 8ft 8in at platform height. I'd be astonished if the LNER gauge was wider. I doubt all 8ft 8in would be available though because of throwover. 9ft was available more than 3ft 6in off the railhead on the GNR. My study needs a LNER composite gauge, I'd like to see one.
     
  9. Hermod

    Hermod Member

    Joined:
    May 6, 2017
    Messages:
    365
    Likes Received:
    74
    Gender:
    Male
    Location:
    Klitmoeller,Denmark
    Heritage Railway Volunteer:
    No I do not currently volunteer

    The Robinson GCR 2-8-0 war engines were 8 feet 10.5 inches over the Cylinders.
    LNER bought quite some of them.
    The drawing of the original P2 cylinderblock shows 8 feet nine and a half at 3 feet and 6 from rail top
    Loading gauge must have been more than 8 feet 8 on parts of LNER
     

Share This Page