It's taking me a while to get my plans detailed. I'd put up my drawings, but they have been changing/evolving with embarrassing regularity. I've laid down some pretty hard qualifiers - and they are proving very difficult to meet. Of course, I realise that I'm being too idealistic. For the most part, real railways don't have a lot in the way of sharp curves, and my chosen locations reflect that. This is good because my building is long and straight....! So far so good.
The rub is, that as I got greedier, I added more real-estate, and now I'm right at the limit of the real-world real-eastate I can utilise... However - to keep the existing bridges in the correct locations as scenic-breaks means that I've really gone 'a bridge too far'. One less bridge leaves me with a wide four-track, three-span brick bridge - hard to disguise as a tunnel or scenic-break. One more gets me back to two tracks, really but I'm overshooting length-wise - which is the planning juncture that I'm at.

I''d laid-down a 'rule' that I'd (Ideally.) neither foreshorten nor 'bend' reality just to get it to fit - and now I'm faced with exactly that. I am modelling .63 miles, or about 1 kilometre of mainline - at 1/76 that's just over 13 metres...and I have 14m max..... Everything else fits fine, as the P4 branch-line sections are well within the limits of the available space.
Obviously, the OO mainline can turn tightly past the scenic-breaks out of view, but I'm still struggling. It's very frustrating after already opting for quite a long extension to the building. If I go for what would be, in RTR terms, a 3rd & 4th radius respectively to the hidden ends of the layout, my outer track would have a centre-line radius of 572, call it 600, or approx' 1,200mm of space needed beyond the bridges. I'll find a way to wangle the last 200mm or so, as it's sooooo close. There is a utility at one end of the woodshed that I may be able to penetrate locally just to wangle the last bit - or might just be able to add it onto the other end. I'll find a way.

One of my last 'tweaks' has been to turn the whole layout basically through 180 degrees. One might think this was little help, but this has used the slant across the room to give me a few more inches. This up-ending of the whole set-up has also made access to the inside of the layout a bit less problematic too.

Now that things seem to have settled, I'll use the next Blog to introduce the location being modelled - but below is what the location looks like in modern times.