Building a nolix layout is more exacting than slapping flex
track down on a sheet of plywood and hooking up the power.
Because much of the track is on a grade, care has to be taken
with spur tracks where cars are spotted. Unless some kind of
a brake is provided, or the spur is built to be level, cars can roll
away. A large switching area like a factory or sawmill would
almost certainly have to be level. If the switching area has sev-
eral connections to the main, that flatness can eat up a lot of
main line length that could otherwise be used to gain altitude.
Passing sidings are less of a problem, as long as the locomotive
remains connected to the cars at all times.
The original discussion, with more photos and plans:
