Factorio Forums

I have quite a large rail network, and I'm using LTN. I get to a situation where all the trains just sit there like they;re waiting for things to happen. I understand the rail signals, but when you end up with a complex network, it doesn't matter how many you add, you either get everything waiting at stops, or two trains facing off against each other going in opposite directions. I've tried things like creating multiple routes, but the pathfinder is not helping because it's trying to find the "most efficient" route, which sometimes means going past signals and being slow...

Is there a formula to a really good, fast moving train setup, which doesn't have things blocked and waiting for trains ? Is it putting chain signals at every intersection, or something ? Looking for some advice, as this is one of the few things in the game which really frustrates me..

This sounds like 2 or 3 problems at the same time

Sitting at stops, waiting for something to happen.
Do you mean LTN stations, designated as depots?
If so, it might be LTN signals not setup correctly (supply/demand)

2 trains facing each other
Totally looks like a signal issue. Nothing LTN can ever solve, you need a working train system first.

I'd solve the latter first. Learning good intersection design is key to (almost) every Factorio rail system
From what I read into your post, it's even more back to basics than intersection.

Are you using any major rework mods?
As production lines (for example in A+B) are all over the place, you could not easily split up rail networks on their own. And in that case you'd need to separate LTN logic into non interacting network IDs too.
But that seems kinda pointless?

Anyway, I think more information about how your base and game settings look like is needed, to be of any help.

The problem is that the rail network has about 30 LTN stops on it, with 10 bi-directional trains which all return to the depots. I think I was trying to be careful and not use too many signals, but I grabbed the RailSignalPlanner and was suprised that it painted about 60-70 chain signals all over the place (which was the opposite of what I was trying to do, to keep things tidy). However, this seems to have resolved the issue to a certain extent, and the trains do seem to be flowing better now.

So my attempt to keep things looking nice, seems to have been my downfall. Answer, put chain rail signals EVERYWHERE...

So this has nothing to do with LTN.

I don't think using a mod to place signals is a good idea. Now I'm interested to see the map

It's not LTN specifically, apart from the fact that LTN allows the trains to dynamically visit stations based on requirement. This is about the sequencing of signals and allowing stuff to move about a rail network without blocking itself (38 trains, 106 stations - although that includes multiple networks as I use ships as well because it's fun) As to using a mod, I also don't "trust" it, but like to see what it thinks, and then do my own thing off the back of it

Your main base nearly has a rail going in a circle around it. I recommend making that an actual circle and one-way. E.g. all trains go clockwise. That means you can put in lots of plain signals on the circle and use chain signals on the station spokes only.

Further the iron pickup nearly has 2 ways. You could make that another one-way circle so trains going to the iron or copper drive along the top and return on the bottom. Should reduce trains blocking each other quite a bit.

Generally one-way rails allow a lot more trains to go at the same time while two-way rails will mostly allow just one train at a time. So any place where a lot of traffic is going to go you want one-way rails. Either building circles or actually place 2 rail lines side by side.

How do you make a one-way circle.. Is that by putting signals on just one side ?

Zarnoo wrote: ↑Tue Aug 24, 2021 8:11 am How do you make a one-way circle.. Is that by putting signals on just one side ?

Yes, exactly that (the right-hand side in the direction of travel).