Some train modelers start with making an exacting plan. I am fairly sure there are people who print out to scale track plans and place them directly on their bench work. I salute you who do, but I do not. I start with general ideas: what genre I want to model, what elements would be interesting and fun to include–bridges, tunnels, elevation, water ways, ect., and space limitations. 30 years ago I would have been happy to squat and waddle like a duck to the doughnut hole in the center of my layout and make the trains buzz around my head…older you get the more tired that shit gets. I need at least 24 inches of free and clear path space around the layout, 36 inches would be even better. once the space determination is met I build the bench work and then go from there.
As this was my first layout in 30 years and I have young kids one element that was sacrosanct was that the trains needed to go around in a contiguous loop. Few eight year old kids and still fewer 2 year old toddlers want to watch daddy play in elaborate and boring switching yard. So the BYLLR is basically a double dog bone (in an L formation, 8 x 4 x 10 with a 36d circle at the nexus of the two dog bones.
That Inter Mountain F7 was a shitty introduction to DCC and ebay by the way (more on that in another post). Once I got all the physical dimensions for the bench work figured out I then returned to the more abstract planning of the genre; in my case this is a vertically integrated corporation which goes from the stump to the pulp dump. Any legit logging operation requires at least 3 elements: a site, a sort and booming ground. In my case I am vaguely going west coast British Columbia with river, rail and ocean conveyance of the logs to the mill. The rail end of it will move from the sorting yard to the booming ground at the pacific ocean’s shore. The two main influences here are my time working as a logger in the Cascades and Costals and Canfor’s now defunct Englewood logging operation. For all you proto fanboys out there watch the video and see just how pitiful small your locos actually are compared to west coast timber.
This brings me to the third point. Imma scale nature 1:87, not 1:100 or 1:120. My personal take is that the trains become more interesting the smaller you make them look.