... I have to ask myself - why would you want to lay out your cork roadbed without at least one turnout already in hand? After you have designed your track plan, the best way to get the cork centerlines is to actually lay the real track out on the plywood or foam surface, and mark the centerlines. Take up the track, lay the roadbed, then reinstall the track. Very few of us lay track exactly as the computer program specifies.
just my thoughts
This is a very good point: no matter how much planning you do, sooner or later you're going to have to lay some track. (Well, you don't really
have to, but in that case, you should really go out and buy a nice comfy chair)
I had a trackplan drawn for my layout, but threw it away when I lost almost half of my layout room to other family uses. Actually, it wasn't even much of a trackplan: a dimensioned
sketch of the room, with some track lines
sketched in, plus a few notes on industries or features. For the current, oddly-shaped room, I built open-grid benchwork in 8' or 10' sections, the widths dictated by the aisle width that I felt necessary.
Then I made a dimensioned drawing of what I had,
sketched in some
new track lines, and went out and bought an Atlas Code 83 #6 switch and a case of track. Next, I cut up a sheet or two of 3/4" plywood into various radius curves, starting at 30", 32", and so on. Using the curves and pieces of 1"x2", 1"x3", and 1"x4", I laid out various configurations until various sections began to look like what I had in my head (ewwww!!)

I made some cardstock copies of the turnout, dropping them in to see if they'd fit, then re-arranging the curves and lumber until I liked it
and everything fit. You can see the reason for choosing flex track, I'm sure, and you might want to keep that in mind, no matter how small or simple a layout
you might have in mind.
From there, I simply fastened the roadbed in place, adding risers where I thought they were needed, and so on. The only area that was later changed was to remove a crossover between the two mainlines on the curve between Lowbanks and Port Maitland, pictured below. It was behind the overhead crane, just ahead of where that loco is heading into the curve.
Now, lest this sound all too haphazard, I
did have a very clear picture in my mind of what I wanted, and for the most part, I got it. I just couldn't see any point to wasting time putting my thoughts down on paper. I did the same thing when I built my house. I had to have blueprints for the town building department, in order to get a building permit, but almost the only time that I referred to them was to make sure that I placed most stuff where I had told them I was going to place it. It wouldn't do to have the inspector get lost on the site!

ops: :lol:
If you enjoy the technical aspects of trackplanning, by all means indulge yourself. I enjoyed sketching trackplans, too, but not with the details of curve radii and turnout dimensions crowding out the imaginative side of the task. Sooner or later, ya just gotta lay some track!!:grin: :grin:
Wayne