Factorio Forums

But I'm having trouble with this 1-way to 2-way to 1-way bit of rail: As you can see, the train in the top right has no path, yet I've proven, by manually driving it through it's entire route that I does in fact have a 'physical' path to its next destination. So the problem isn't with the track itself, but the signalling.
This rail network also crosses another 1-Way loop to the SE, but I've signalled 1-way crossings (the type where they are still effectively separate but overlapping 1-way rail lines, meaning the train on one network can't physically get onto the other) before and had it work flawlessly (chain before, regular after for both lines at each overlap).
This makes me think the issues much all be in the 1-way to 2-way transitions. I've signalled them with chain signals before the merge/split and regular after (for the intended direction(s) of traffic flow), and sure enough, all signals are green...so what am I missing? Why won't the train go?

The normal/chain signal pair at the merge point does not seem to be lined up correctly.

DaveMcW wrote:The normal/chain signal pair at the merge point does not seem to be lined up correctly.

When I mouse over it, they both have the same bit of track highlighted green, isn't that correct?

two-way tracks need to have their signals "paired" on either side of the track. one-way tracks just need signals on the right, so obviously nothing to pair with so no issue.

paired in this case means *exactly* opposite. when a signal (of either type) is placed, it makes a line across the track - the "paired" signal needs to touching that same line
green squares around good placement, white arrows pointing at the 'lines' I'm talking about. red squares around bad placement (even though, in the up/down, left/right tracks, the signals are on the same segment)

sorry if I'm over-explaining, but this might be viewed by someone else with a similar issue, so best to err on "too much info" side?

Looks like alignment at the NW merge was the problem, moved the normal signal there one space over (lining it's yellow light element with the chain signal on the other side) and voila, train moved, we'll see if it handles the trip in the other direct ok, but I suspect it will).