Factorio Forums

I cannot figure out train signals. They behave in the opposite ways that I think they should in every test I do, and I am beyond frustrated at this point.

I have 2 iron mines on either end of a single, non-looped track.

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On this track are two trains - each with engines on either end so they go back and forth on the same track.

In the middle of the track is my base, with a single spur off of it to the iron drop-off point:

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All I want to do is have my trains wait before entering the spur if there is another train present. It shouldn't be that fucking difficult, and I feel stupid that I can't figure it out.

Can someone please tell me, step by step, how to properly signal this intersection?



https://i.imgur.com/dt9H5lr.png

Something like this:

Here is what happens when I do that:



https://i.imgur.com/xloVrOq.png

I typically don't try to run more than 1 train on two tracks, but I think it will work if you replace those regular signals with chain signals. (In general once you need more than 1 train using a section of track, it is easier to upgrade to a dual track system. (Dual track also offers much better throughput, and scalability).

The general tutorial for signals I recommend is https://www.reddit.com/r/factorio/comme ... ts_23_and/

A forum post specifically about two way rail on a single thread (ie your situation) viewtopic.php?f=194&t=53937 .

You can simply remove the two signals on the horizontal part of Mr. Tacts example for it to work without chain signals, but keep in mind that no matter how you signal this, you can only have two trains running in total with your setup.

Jesus christ, why didn't anyone say that you have to signal every fucking intersection the track runs over no matter how far away or how feasible it is for a train to turn at it?

That would have saved me so much heartache and frustration.


https://i.imgur.com/bNQVIJT.png

With chain-signals you could do it like this. But basically all you need (as stated above) is regular signals after the split.

Locane wrote: ↑

Sun Jan 06, 2019 1:11 pm

Jesus christ, why didn't anyone say that you have to signal every fucking intersection the track runs over no matter how far away or how feasible it is for a train to turn at it?

That would have saved me so much heartache and frustration.

Yeah, why would people answer the specific question you actually asked instead of assuming that you generally have no clue and did not find it necessary to learn the absolute basics yourself or spend three minutes on the train tutorial...

This isn't the answer you are looking for.

If that were my logistics, I would split the track into two. That way you don't have to deal with a train being stopped unless it's loading/unloading. Trains stopping without getting/moving items is a waste.

Just by adding a bit of belts/underground belts you could more than make up for the slight loss of distance traveled.

This is of course if you don't absolutely have to have the train unload into the base.

Derp. Sorry about that. Should have known better than to suggest (without testing) a setup I wasn't extremely familiar with. That's the thing about rail signalling, even when you've played for thousands of hours you can still mess it up...

The general rule of junctions is:
- Full signal after the junction
- Work backwards
- Chain signal every single place that rails cross until you reach the start of the junction
- Don't space your junctions any closer than your biggest full train length

Single tracks are much harder to signal than twin 1-way tracks. Start with 1-way tracks, it takes more rail but it will make your life a lot easier.

There are more fancy ways to get things done but follow these steps and it'll solve 95% of your railroad troubles.

Locane wrote: ↑

Sun Jan 06, 2019 1:11 pm

[profanity], why didn't anyone say that you have to signal every [vulgarity] intersection the track runs over no matter how far away or how feasible it is for a train to turn at it?

That would have saved me so much heartache and frustration.

Probably because it isn't true?

The basic rule of thumb is that you use chain signals before an intersection and regular signals after. That way you don't block the intersection.

But it really depends on your layout. If you have one train, you don't have to signal anything. If you have two trains, you only have to signal the part they share, so they don't both go at the same time.

If you have one-way tracks going in opposite directions, it makes things much easier. You'll save yourself a lot of trouble until you get better at signaling.

And when you get better at signaling, hey, then you won't have to cuss at all of us just because you don't understand how it works.

bobucles wrote: ↑

Mon Jan 07, 2019 4:41 pm

The general rule of junctions is:
- Full signal after the junction
- Work backwards
- Chain signal every single place that rails cross until you reach the start of the junction
- Don't space your junctions any closer than your biggest full train length

Single tracks are much harder to signal than twin 1-way tracks. Start with 1-way tracks, it takes more rail but it will make your life a lot easier.

There are more fancy ways to get things done but follow these steps and it'll solve 95% of your railroad troubles.

What about for tracks that merge (rather than cross each other)? Should you use a chain signal or a normal rail signal in these situations?

je11693 wrote: ↑

Mon Jan 07, 2019 9:26 pm

What about for tracks that merge (rather than cross each other)? Should you use a chain signal or a normal rail signal in these situations?

give the track with higher priority the normal signal
if there is no priority it doesnt matter which one you use

A chain signal looks ahead along the tracks to the next signal(s)on that track.
Simplified:
- all signals ahead are red -> red
- at least one signal ahead green -> blue
- all signals green -> green
- no other signal found -> any train anywhere on the rails somewhere ahead of the signal will turn the chain signal red. This includes crossing tracks.

disentius wrote: ↑

Tue Jan 08, 2019 5:54 pm

A chain signal looks ahead along the tracks to the next signal(s)on that track.
Simplified:
- all signals ahead are red -> red
- at least one signal ahead green -> blue
- all signals green -> green
- no other signal found -> any train anywhere on the rails somwhere ahead of the signal will turn the chain signal red. This includes crossing tracks.

Chain Signals only look ahead to the next signal along only. Not all of them.

@blinky: Should have stated that more precise.
They look one Block ahead; and a block can have more signals at the other end. (hence the "blue" signal)

@Disentius Yes! Of course you are correct. I was just talking simplistically.

@blinky:
So was I. Thanks for forcing me to explain.