No dynamic train refueling yet?

[chris13524]

I could've sworn that one of the FFF's talked about the ability to conditionally go to stations (e.g. if fuel is low or it got a circuit signal from a station). This would allow the ability to automatically go to a refueling station when the fuel is low.

This isn't as much of a problem when you only use trains to deliver between outpost and base as you can simply refuel at the base. However I'm pursuing more of de-centralized base setup with trains transporting steam (for power) and resources between all the different things. In this circumstance, it's more difficult to determine a "host" end of any schedule (the one that would supply the fuel) and even more difficult to transport fuel to all the places.

Anyways, it would be great if there was the ability to visit stations conditionally. Of course this also requires the ability to read fuel level which I don't think there is any way to do that currently.

[MobRules]

There are mods that do that, but I must have missed that FFF.

I also prefer decentralized train-based factories. Ways I've handled this in Vanilla:

• run yellow belts parallel to the tracks, topping off fuel at each station
• have a coal train (or several) that drops off coal at each station to top off trains at each site
• Have strategically placed refueling stations, and have every train include one in it's circuit, set to wait for "inactivity".

I play more often with mods, though, which opens up many more possibilities.

[zOldBulldog]

The best way I found to do this is with the LTN mod.

Besides allowing for a much more efficient method of using trains, you refuel at the depot(s) . That will ensure that your trains remain topped off.

[Koub]

I know I've seen suggestions asking for the ability to read locomotives' contents, but I don't remember seeing that in a FFF.

[astroshak]

I just pick a side : pickup or drop off.

I add a Fuel Train Station to that side. And it carries fuel for the trains that use that side. Put such a station at all your train fed minifactories, and turn it off when you have sufficient fuel.

Then just set up a refueling supply station for the fuel train to go get its fuel, and its cargo, from.

[Amarula]

I just pick a side : pickup or drop off.

I have been doing this, and it works well for a small base.
I chose drop off for fueling, because it didn't make sense to me to send fuel out to all the resource fields for the ore trains, and my OCD didn't like the idea of using pickup for some and drop off for others. Of course, acid for uranium mining is an exception

However, I found as my base grew, one fuel train wasn't keeping up, particularly to deliver fuel fast enough to the smelters where my ore trains picked up fuel (and yes I know it is going to be more efficient once I push the smelters out to the ore fields and deliver plates instead of ore but that is a separate challenge). I've been playing with the number of fuel trains (and how to keep them all from trying to top up the same stations, while leaving other stations out of fuel), as well as the size of the local fuel stockpile. Starting to transition to nuclear fuel, so hopefully that will extend the refueling interval enough.

I have agreed with all the requests for conditional train routing, that would be so convenient for refueling and many other uses, but I have also found it an enjoyable challenge figuring out to make things work without it.

[chris13524]

However, I found as my base grew, one fuel train wasn't keeping up, particularly to deliver fuel fast enough to the smelters where my ore trains picked up fuel (and yes I know it is going to be more efficient once I push the smelters out to the ore fields and deliver plates instead of ore but that is a separate challenge). I've been playing with the number of fuel trains (and how to keep them all from trying to top up the same stations, while leaving other stations out of fuel), as well as the size of the local fuel stockpile. Starting to transition to nuclear fuel, so hopefully that will extend the refueling interval enough.

You mention you use more than one train to deliver fuel. How do you prevent multiple refuel trains from pathing to the same station? The details of the train routing voodoo are still unknown to me, does one train "reserve" that station and the next train picks a different station? What happens if there is only one station enabled and more than one train ready to deliver fuel?

[zOldBulldog]

The depot based solutions (where trains wait at a depot stacker until needed) seem to be the best for refueling and routing.

- LTN is excellent if you want to use mods.

- Haphollas is an excellent "limited version of LTN" design pattern that you can implement in vanilla. You can even find a youtube tutorial by Nilaus about how to do it.

But I do agree... it would be very nice if someday the devs replaced all train handling with something much more robust and flexible. But I somehow doubt that they want to go that route anytime soon.

[Amarula]

You mention you use more than one train to deliver fuel. How do you prevent multiple refuel trains from pathing to the same station? The details of the train routing voodoo are still unknown to me, does one train "reserve" that station and the next train picks a different station? What happens if there is only one station enabled and more than one train ready to deliver fuel?

Sadly I do not have a way to prevent trains from competing to deliver fuel. What I do have is an estimate of how many fuel trains I need (based on visually scanning the map to see how many stations are requesting fuel at the same time, and only adding more fuel trains when the current set can't keep up), and a 'zone' system, where each fuel train has one specific stop where it is the only assigned train; once the train has delivered to that stop, it will be closer to other fuel stops in that zone, so those stops no longer get starved for fuel. I haven't had a train out of fuel warning since switching to these zones for my fuel trains. I do still get trains running from one end of the map to the other only to be beaten to a requesting station, but because of the unique zone stop, the train gets sent back to its assigned zone.

Again from observation, I see that for my base it may take up to three minutes for a fuel train to get to a stop requesting fuel, so I have set my local fuel stockpile to last five minutes. And that amount varies depending on how many trains use the stop, how busy those trains are, and how long their delivery runs are. The fuel train delivers to its assigned stop, then two other stops before returning to the fuel depot to pick up more fuel. Most of the time, the fuel train has enough fuel to handle at least two more stops, but by making fewer drops I am sure that the train won't be empty ever when it goes to deliver.

I had tried using zone-specific names (Z1 fuel stop, Z2 fuel stop etc) so each fuel train only served stops in its zone, but it didn't work as well: zone 1 would be (temporarily) fueled up, so nothing for the Z1 train to do, while sometimes all the other zones had stops waiting for fuel. By using neutral names (fuel stop), all the fuel trains can help each other when needed. Also, it was a lot more tedious work assigning and reassigning stops when I added a new zone.

So to answer your question, when only one stop is requesting fuel, all my fuel trains head for that station. Fortunately for me, that almost never happens.

[csduff]

I've suggested this in another post, but if mods are the way to go...

https://mods.factorio.com/mod/FuelTrainStop

You create a special type of Fuel train station. For any train low on fuel it creates a temporary stop with inactivity (2 seconds, I think). Train goes there, refuels with whatever you feed it, then goes on its merry way.

The only issue with this is that it will load to any slots you have inserters at. E.g., if you have a fuel stop setup for LL-CCCC, then you send a L-CC train to it, the first cargo wagon will start filling with fuel. It's fine for me, as I always use L-CCC-L or L-C trains. Now that I think about it, I also use LTN, so I wonder if there is a way to use LTN's combinator logic with a non-LTN station.

[mergele]

@Amarula Hmmm, I think I'm gonna just rip your idea and use it for my current world. The possible growth limitation on a single fuel dispenser station has been quite shadow on my mind (although it's probably still very far away). Though I think I'll put an additional layer on it by having a single central fuel source station, which delivers fuel to the distribution stations which then distribute it to all the other stations. That way switcing between different kinds of fuel and keeping the fuel distribution stations stocked when their coal fields empty should be a breeze.

[Rjskeet]

This might sound a little dumb but when I do this I usually have a grand station of sorts where all trains stop and trade with other production lines so every smaller factory is built around 1 train and I just add more train/factorys as needed and all trains are fueld at the gs

[csduff]

I've suggested this in another post, but if mods are the way to go...

https://mods.factorio.com/mod/FuelTrainStop

You create a special type of Fuel train station. For any train low on fuel it creates a temporary stop with inactivity (2 seconds, I think). Train goes there, refuels with whatever you feed it, then goes on its merry way.

The only issue with this is that it will load to any slots you have inserters at. E.g., if you have a fuel stop setup for LL-CCCC, then you send a L-CC train to it, the first cargo wagon will start filling with fuel. It's fine for me, as I always use L-CCC-L or L-C trains. Now that I think about it, I also use LTN, so I wonder if there is a way to use LTN's combinator logic with a non-LTN station.

For anyone who is interested, I did set up something with LTN and the Automatic Fuel Train Stop mods.

The Automatic Fuel Stop doesn't output LTN signals (obviously, in hindsight), so you can't directly use it to get train configuration information.

However, I created a Fuel Stop station, that wasn't actually on a train line. I then created an LTN stop with the same name (the naming is critical) that was connected to the main train line. The LTN stop does show a purple light, indicating a duplicate station name, but this doesn't hinder the functionality, in this case. When trains are low on fuel, they head to the LTN station, refuel, leave the station and delete the temporary stop, then go on their merry way. I have trains of L-C-L, L-CCC-L, and a personal train of LLLLL. This station will fuel them all accordingly, without inserting any fuel into the cargo wagons.