Factorio Forums

Hey guys, been playing for over 200 hours and really just now getting a game going where I need a strong train system to finish this game. I am playing with RSO so I have to actually go out and create resource mining outposts, and natural evolution so the enemies are actually a challenge. And I tell ya the combination of those two mods is tough! The biters are actually extremely challenging to defend against! On top of that I am playing with the Space Extender mod so I am needing a very large amount of resources.

So now on to what I need help with. Rail signals.....are so confusing! I have watched a few differnet videos and read a couple tutorials but still cant manage to figure it out. I will show you a picture of one part I am having a problem with, please read below for an explanation.




So this is my home base Iron dropoff point we are looking at. I have two iron outposts, one south the other east, way far away from my base. You can get another look at it from the minimap. The train from the east iron outpost comes in on the bottom track and leaves on the top. The train frmo the south outpost comes in on the right track and goes out on the left. They move clockwise around the "loop". I cant figure out how to setup the rail signals. I havent had em crash into eachother, but I am of course trying to plan to prevent that. However, nothing I do seems to realy work and the trains always just get stuck at some point. Ignore the current rail signals I have placed because I have just been fiddling around with them for awhhile. Any help guys?

You need a signal (or paired double signal for 2-way track) on every track that touches an intersection. You are missing the east and southeast signals on that intersection.

These are all 1 way tracks (so far). So I put a rail signal on the right side of the track before the intersection, correct? For some reason I feel I've done that but it hasn't worked Do i need one on the other side of the intersection as well?

when using signals for multiple trains every train has to have a set of signals for it. one in front and one behind it somewhere. signals create blocks of track in front of and behind the signal and that block continues along any connected piece of track no matter how they touch each other. only one train can be in a block. if you hover the mouse over a piece of track it will have a block number in the info panel. ill post some images to help show what ive said later when i get home

Three basic rules are: 1) Every track into a junction needs a chain signal, 2) every track out of a junction needs a regular signal, and 3) signals inside a junction are optional but if you want them (to allow multiple trains to use an intricate junction at the same time) then they should be chain (this doesn't apply to your case though). Keep repeating those rules to yourself while building and your should be ok. There are some cases where the rules can be broken, but for a beginner it's easier to just follow them all the time. In your screenshot you have several tracks in and out of your one crossing on the bottom without signals on them.

Thank you for all your help guys, I do appreciate it. I took all the bits of knowledge you offered and feel like I do actually understand how it works now, which makes designing things much easier. I still havent used chain signals, nor do I know when, but I will cross that bridge when i come to it.....which might be now for all I know :p I have expanded my rail system a good bit, going to fetch resources all over now. Things have been running smoothly for a long while now, but now I have found my trains stuck. I can easily manually fix this, but can yall tell me what is wrong with the design to where this would occasionally happen?


Daylight:


Night:


The train carrying copper is currently heading back north out of the base, and I can see why this problem is occuring. Please note that after taking the night time picture, I deleted a couple lights, then took the daytime picture. Please look at the nighttime for the original setup.


Thanks guys

This is a perfect example of when you need chain signals.

The westbound train stopped in the middle of the intersection, creating a giant traffic jam. If you had put a chain signal before the intersection, the train would stop before entering the intersection.

In general, chain signals before intersections, normal signals after intersections.

So what is it exactly that chain signals do? I hear you when you say in general, put em before intersections....but why? Whats the function behind them?

General signal functionality (both normal and chain) is to divide track into blocks and prevent more then one train from entering given block.
Important point is that for blocks it doesnt matter if track actually connects - perpendicular intersection will also make one block from both tracks.

Chain signals build up on this basic functionality by considering exits from the block they are guarding that are accesible from it's point. For this check track connections matter - chain signal won't look at exit from track that is not accesible for train coming to it.

Checking state of exits means that chain signal will prevent train from entering the block if it can't exit the block guarded by the signal. Thats why you place them before the block with intersection - it prevents trains from entering the intersection in question if they can't leave it. This prevent a train from stopping inside the intersection block and potentially locking other trains from using the intersection causing a dead lock.

Check out https://wiki.factorio.com/Rail_chain_signal

My rule of thumb:

If you don't want a train to wait at a signal go upstream and replace the signals to that signal with a chain signal. Use normal signals everywhere else.

Heres a new problem I have encountered that I cant seem to figure out. Ive manged to set up a spaghetti monster out of my tracks and everything is working seamlessly and well, except this one bugger.

I have a train that says no path, although I feel I have checked all the signals along the path and they should all be right. The train also does connect to the outpost, as I have




This is how I want the train to go out. I made the little loop below just because the train wouldnt go the other way, but that does not work either.



The problem I think lies in the intersection I created that the train is on top of in the second picture. After the train crosses this point, I can automatically send it to the copper outpost. But whenever the train is on one side of this intersection, I cannot automatically send it to the other station. Can anyone help me figure out why?

i would double check that the first set of signals behind the train are paired correctly or the one after the curve might need moved up a tile. if they are fine try moving the train bit by bit till you find the point where it isnt giving "no path" signal.

Bringing my copper train back home, it just cant make it past this intersection. What is going on here?

I added a rai signal which is highlighted by my mouse in the middle of the screen. That allowed the train to go through the intersection automatically, however it would not return back. So I added the loop back on the right hand side in the picture below, but that did nothing.

could you attach a copy of your save. i dont see the issue in the pic. i can take a look at it and get a better idea of whats not working

I have many mods...I hope that is not a problem. If not could I invite you to to the game?

mods are not an issue. and yes if you like i can join you in a game

Add me on steam: mikedubayou

kk