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I am having a hell of a time understanding how in the world train switches work. I mean I understand the theory and can make small examples that work as designed but when I try to do anything else it never works. I tried to make a side track so trains can pass each other on a long leg of track that goes to a very remote base. with just the switches at the two ends the trains have to wait for each other get into the depot on either end to then leave their station. I added the switches and long break out and no matter what I do I can't figure out how to make them use it without ending up with both of them showing no path. Is there some tutorials or resources that can explain this like I am five? I swear I am a bright person but this crap is just escaping me.

Maybe this Tutorial will help you.

https://www.youtube.com/watch?v=k6wxl4FdSuQ

Greetings steinio

Heh, and after a few hours messing about with it you'll be wondering why you ever had trouble.

Just a note though, the only time signals will EVER cause a No Path error is if they are creating a one-way section of track and the train is facing the other way. From the train's perspective, the signals must always be on the right side of the track. The only time you can have a signal on the left side is if there is also a signal on the right, this makes a two-way section (you need to ensure that two trains won't meet each other head on though!).

So I watched the video and i did finally kind of figure it out. Let's just say I got it working but I still don't fully understand why it is working. But progress is progress.

Not sure when i would need a chain signal as compared to the regular as what i st up worked with either.

As with all things Factorio, I will continue to build and work with it until I get it right...

Try this train tutorial on Googledocs (originally posted by Grays42 on Reddit):
https://docs.google.com/presentation/d/ ... slide=id.p

It's a clear, illustrated set of slides on how to set up a rail network and why it should be done that way. Chain signals are important as you get more trains, especially for junctions where rails cross one another, to prevent deadlock where none of the trains can move.

sholcomb101 wrote:Not sure when i would need a chain signal as compared to the regular as what i st up worked with either.

Technically you don't really -need- chain signals. Consider if you have a 4-way intersection you can just put signals on the entrances so only one train can be on the intersection at a time and you'll never have any problems. However, you will have a lot of trains stopping needlessly and if the intersection is busy this can lead to long queues.

However if you put a signal in the intersection, you'll have trains stopping in the middle of the junction and preventing other trains from crossing. For example if you have a train going east but there is a train there already blocking its exit from the junction, you don't want it stopping on the junction and blocking north and southbound trains. Therefore you use chain signals to keep your junction efficient while ensuring nothing gets backed up or deadlocked.

The rule of thumb is to put chain signals down before any place where two separate tracks meet (where trains can collide with each other) however I also put chain signals down immediately after, and on any exits. Just fill the junction with chain signals (well, not on every block but you get the idea). I don't know if it's best practice but after observing a junction for a while I noted normal signals on the exits are bad because trains could potentially stop there and block the intersection, and also I had for example a westbound train stopping for an eastbound train even though their paths never crossed.

For basic use they allow for large intersections that don't hold up everything whenever there is a train already on it.

Deadly-Bagel wrote:

sholcomb101 wrote:Not sure when i would need a chain signal as compared to the regular as what i st up worked with either.

The rule of thumb is to put chain signals down before any place where two separate tracks meet (where trains can collide with each other) however I also put chain signals down immediately after, and on any exits. Just fill the junction with chain signals (well, not on every block but you get the idea). I don't know if it's best practice but after observing a junction for a while I noted normal signals on the exits are bad because trains could potentially stop there and block the intersection, and also I had for example a westbound train stopping for an eastbound train even though their paths never crossed.

For basic use they allow for large intersections that don't hold up everything whenever there is a train already on it.

...which is why intersection exits should always have space for your longest train between the exit signal and the next signal down the line. If there isn't that space available, you would need a chain signal instead of a rail signal at the exit.

Yes however using chain signals you get better response times when a train leaves the intersection so queued trains can enter it sooner.