The narrow gauge track (which is barely 36 inches of plain line!) is finally all in place. The original idea was for a feeder from a mine at the back of the layout to the processing plant, as shown by the red line here:
I also thought of running the NG line around the back of the processing plant on a low embankment. Unfortunately, the success of my hand-built points inspired me to tackle a flat crossing over one of the SG sidings. At much the same time I realised it would be better to have the mine off-scene (above the fiddle yard), and not behind the layout, where I could only use it at an exhibition because the layout sits against a wall here at home. And so, the longer SG siding was shortened, the shorter siding was lengthened and I have finally ended up with this:
It has all taken rather a long time because I have been somewhat bitten by the flexibility of an open-top baseboard and decided to build the NG line on a gradient to make it more interesting. This means, the SG sidings and the flat crossing are on the level, but the NG line rises behind the processing plant, and drops away across the exit to the fiddle yard:
The white track base is 3 mm foam board to match the 3 mm cork under the SG sidings and allow me to go upwards and downwards. The gradient downwards here is about 1:21. And, as if I needed more, the NG line becomes a tramway so it can share a bridge with an access road to the processing plant. To do this I have put a step in the track base and glued the rails directly onto the track base over the bridge.
I think the tramway ought to be along the crown of the road but this would have meant a very tight curve on the NG line, so I have stayed with a 9 inch radius and I now see the bridge on a skew as shown by the steel rule (as a pavement) and the pencil (as a bridge abutment):
So, I have now set myself to build a skew bridge with a gradient on the road surface and a hidden track running across the middle. And I need to add a high-level NG deck onto the fiddle yard.
This is either genius or insanity, but I do like having all the angles. Please do add comments if you like, I am happy to add extra details (or corrections!) to these blog posts.