... servo to push it over the moving elbows. And another thought reinforces this when I consider that unlike normal switches which have far less metal in them, the moving elbows are pretty well a full rail cross section for almost all their length. I've uploaded a copy of the relevant area of the slip I'm building in the hope that it all makes sense. And I've pencilled in the approx position of the support rails either side of the movable elbows. Alternatively page 53 of David Smiths book will make it clearer I suspect. 2787_121516_300000000.jpg The X is the probable hinge point for the elbow and the lines either side are the lateral support rails which I have to confess I didn't know existed before now. Kind regards Andrew Last edited on 12 Aug 2019 20:25 by Andrew Duncan posted: 13 Aug 2019 16:08 from: Tony W Hi Andrew. You may find this picture useful. It appears GWR. You have answered one of my questions as to what the additional pieces of rail were for. 2151_131059_030000000.jpg There is much detail here, the ...