Trains should go straightly as possible.

[yagaodirac]

When we build multi lanes, trains go like snakes, stop other trains.
Shouldn't be very hard?

[robot256]

Trains always take the shortest route, unless it is blocked for a long time. There is no human-intelligence dispatcher to assign each train to a different track. You must do it yourself by how the junctions and signals are laid out. For example, you make the right lane forced to turn right at junctions, so trains only use it when turning. Then put only one lane changing crossing in between junctions, so trains cannot stay in the wrong lane very long.

[ssilk]

There was an interesting post about pathfinding on Reddit https://www.reddit.com/r/factorio/comme ... visualized


Btw same guy posted also https://www.reddit.com/r/factorio/comme ... using_rail

[mrvn]

You can put a station or a circuit controlled signal at the lane changer. (The circuit controlled signal must be red until a train goes that way (signal before it != green). That way going straight is cheaper.