Some of you may think that a layout started 20 or so years a go would now be finished. If so then you are wrong as there are lots of features still to be added as well as some upgrades.
One of the upgrades is get a more realistic signal operation using a lever frame instead of the current buttons and switches.
For this exercise we need to first agree a signal diagram and then produce a locking chart. Yes we are going to have proper interlocking!
When I built the signal box it had installed into it a lever frame of 17 levers as this is what was installed at the three stations along the line. However the signal diagram for the model was far more extravagant. This was partially due to a lack of available material and the assumption that all movements would be controlled by a signal. As we shall see this is not always the case.
Doug did at some point acquire an MSE lever frame that had been made up with an interlocking shelf. (I can't think of a better word to describe it here so please educate me) His plan, and the plan of others who have looked at this was to reuse the metalwork for Swaynton. All without success. There have also been thoughts on electronic interlocking but this too has come to nought.
So the frame is now with me and the task is to produce a lever frame based on prototype operation for this layout.
The first place to start is to look at the signal diagrams for the three stations that Swaynton is based on. These are New Milton, Hinton Admiral and Sway. You can find low resolution images of these on the Signal Record Society (SRS) website. Just look for Drawings and click down the links. These stations are on the Southern, Section P: LSWR Worting Jct to Weymouth & Branches. Examination of the diagrams finds that Hinton Admiral is a "Dead Ringer" for Swaynton with the exception of the advanced up starter.
So I have taken this diagram and turned it upside down as we operate from the back, so the operators signal box is on the wrong side of the tracks, and made an executive decision to plan the removal of the advanced up starter.*
So I now have a Signal Diagram.
Swaynton Signal Diagram.pdf 173.87KB
Next up will be the locking or dogging chart.
*Well I did see if the up starter could be kept and there are two spare levers, but then would I have to signal the up crossover? It seems easier to stick to prototype.