Prototype LNER J39 drawings - which ones do I need?

Discussion in 'Resources' started by Dog Star, 4 April 2019.

  1. Dog Star

    Dog Star Western Thunderer

    Sometime back I asked Rob Pulham about a General Arrangement drawing for this engine and Rob has obliged with two drawings which looked, initially, to be just what I wanted. The initial euphoria on receiving the drawings faded when I realised that both drawings were "Pipe and Rod" arrangements - fine for details, not quite there for motion work and that was the reason for the request to Rob. Thankfully, the drawings from Rob carried annotations which suggested where the drawings had come from and hence an internet search plus a heavy content of "control F" confirmed that these pipe and rod drawings were amongst several other drawings for the J-39 class... to be found in the Darlington drawing list of the NRM.

    What is wanted is a drawing or drawings which provide the arrangement of the valve motion for a J-39 and details of the motion plate. Searching the NRM Darlington list provides these entries:-

    1/ dwg. 11755 of 22/01/1926, frame stay;
    2/ dwg. 11810 of 08/03/1926, motion arrangement
    3/ dwg. 11842 of 17/04/1926, frame arrangement;
    4/ dwg. 16323 of 09/10/1935, frame stay;

    Searching the list did not locate a GA for the class.

    Not being familiar with the way in which the LNER created and named drawings for the design of an engine can someone please confirm that the drawings above do provide details of the valve motion and the motion plate for a J-39.

    thank you and regards, Graham
    Last edited: 5 April 2019
  2. Steph Dale

    Steph Dale Western Thunderer


    You want the motion arrangement.

    Rob Pulham likes this.
  3. Dog Star

    Dog Star Western Thunderer

    Thank you Steph.

    If you know, does the motion arrangement drawing include sufficient details of the motion plate to enable creation of a 3D model?

    Not withstanding the value of Steph's answer, does anyone know what is included in the drawings "Frame Stay"?

    thank you, Graham,
  4. Scale7JB

    Scale7JB Western Thunderer

    I can't help with the drawings, but if the info is of any use, the Laurie Griffin 4f valve gear kit is supposedly very close to that of the J39.

    Rob Pulham likes this.
  5. Rambler

    Rambler Active Member

    If this is like other Darlington drawings that I've seen, the Motion Arrangement will probably show the Motion Bracket in a side view (i.e. looking across the frames) and a top view, in situ. You'll have to work out the shape of any openings - if you can find a photo (e.g. in works, or being scrapped) then you might have enough information.
    If you need a GA then the OPC lists at the NRM could be useful. Two GAs (7037 & 12062), one Frame Arrangement (9943) and three Pipe and Rods (7035, 11052, 11072) are listed. They aren't as good as the paper drawings but they have one big advantage in that you can see them on a microfiche viewer before you need to commit any money.
    Eric Ramsay
    Dog Star and Rob Pulham like this.