train bus factory

[walljaik]

this is an idea started on .12 with a player called Reverend in the WL MP SUG server.
the concept is to have a trainbus, so almost each element is moved by trains to submodules where you get the next subproduct. I0ve been not playing so much cause been on vacation but just fixed the save today and wanted to share.


Anyone tried sth like this? show yours if tried

[ribsngibs]

Very cool. I am working on a base using this concept right now, but it's not really in a good place to show yet. It would be, but I took a detour trying to design an easily buildable and self-supplying perimeter wall and fell into the rabbit hole for 10 hours!

What I'm doing is, since there is so much rail (mine is also a 4-lane track like yours), I'm making a huge tileable rail blueprint which basically is a huge square (a 4x4 intersection on each corner, straight rail along the edges) with two train stops inside (a dropoff and pickup station), with a big empty space inside to be filled with whatever module I want in there (furnaces, or circuit production, or whatever). I'd say the blueprint is at least 2 screens wide and more than 3 screens tall. I'm planning on just spamming those big squares down everywhere and filling the insides with production of whatever I currently have shortages of.

Still trying to decide how to efficiently load multiple items onto a delivery train and get it to where it needs to go. e.g. if I need copper and iron for electronic circuits, should I send a train to the copper furnaces first and fill half the wagon slots with copper and then go to the iron furnaces and fill the other wagon slots with iron, taking two stops and clogging up the stops for longer than necessary, or do I make a central distribution center which takes deliveries of copper and iron and then collates it properly into a "electronic circuit production facility"-specific loading train station, etc.. Just curious how you decided to solve that.

[tzwaan]

I'm doing something similar with a friend of mine right now. Except that we decided that it would be a good idea to try this with bob's mods. Pay in mind that we never played bob's mods before but we wanted to try it out. In retrospect doing everything by trains while trying bob's mods for the first time isn't such a great idea, but after about 80 hours of play we finally got to the point that we have personal roboports, and our train network is already all over the place.
I don't have any screenshots right now, but I was planning on posting them anyway, so I'll get to that soon.

[doxsroxs]

Look a few threads up:
viewtopic.php?f=8&t=25311

Im currently using .14, but think there is a .12 version in there somewhere.
Our system currently have around 130 active stations (also a first time bobs mods user), I also built several special solutions for mining and storage. Its siggyboy that built the base system though. Have a look and dont despair if it looks daunting, I can probably help explain the worst pitfalls so you dont repeat my mistakes

I can also supply blueprints for the depot, would save you tons of time setting up a lot of bobs mods materials etc. I also have newer versions of the stations with tech 2 power poles etc.

[Grimakar]

Very cool. I am working on a base using this concept right now, but it's not really in a good place to show yet. It would be, but I took a detour trying to design an easily buildable and self-supplying perimeter wall and fell into the rabbit hole for 10 hours!

What I'm doing is, since there is so much rail (mine is also a 4-lane track like yours), I'm making a huge tileable rail blueprint which basically is a huge square (a 4x4 intersection on each corner, straight rail along the edges) with two train stops inside (a dropoff and pickup station), with a big empty space inside to be filled with whatever module I want in there (furnaces, or circuit production, or whatever). I'd say the blueprint is at least 2 screens wide and more than 3 screens tall. I'm planning on just spamming those big squares down everywhere and filling the insides with production of whatever I currently have shortages of.

Still trying to decide how to efficiently load multiple items onto a delivery train and get it to where it needs to go. e.g. if I need copper and iron for electronic circuits, should I send a train to the copper furnaces first and fill half the wagon slots with copper and then go to the iron furnaces and fill the other wagon slots with iron, taking two stops and clogging up the stops for longer than necessary, or do I make a central distribution center which takes deliveries of copper and iron and then collates it properly into a "electronic circuit production facility"-specific loading train station, etc.. Just curious how you decided to solve that.

I am having the idea of building a central gigantic depot for each item with storage chests and logistic robots. So you just need one "receiving office" for several trains to feed the storage site and on the other side you build individual stations that transport needed goods to their related assembly sites.

I think this is good, because I am right now facing one problem with robotics network that covers my whole base, which is already quiet big: The bots need to much time to travel because of too long distances.
So in this scenario the logistic bots are only at the depot. So if you as a player need something, you could build a shuttle station at the depot to make the bots feed you with items there.
The rest of the map will be "trainland".
The good thing about using bot network, for the input of goods you do not need to sort. You just can bring it there no matter how your wagons are loaded. So you could use some crawler trains driving from oné output to the next until they are full and bring that to the depot.
For this it would be very helpful to influence the roadmap of the train: If train full, go to this station...
For the output of the depot you just use requester chests, which can be configured quiet precise, like only take 100 blue circuits...
So you only need one train and one station (on each end of the tracks of course )for every assembling site.

[Captain_Meatshield]

I've just started a game with this idea in mind. I figured others may have done it already (I soon discovered Zisteau's "Meiosis" series on YouTube), but I like what you've done with it!
I was going to attempt to run a rail network along the map as though it were a regular belt-bus and have everything branch off that, instead of a more spread out set-up, but I dread to think how large that might turn out! D:

Could be entertaining, though!

[vanatteveldt]

My current base is organized along the same principles.

I actually have two disctinct parts of the network: a branching line to gather raw resources, and a 'bus' that connects the various subfactories. Smelters, refinery, and stoneworks have two separate stations: an unloading station connected to the 'raw' line, and a loading station connected to the bus. There's a connection for my passenger train and for some cross traffic (i.e. stone for the rail production)

It is currently all 2 tracks (1 each way), so far throughput is fine. I might add a third rail system for rocket parts, even though it would be mostly for aesthetics. Maybe keeping plates and circuits separate might be good. I'll post screenshots "as soon as it's done"

[mrvn]

Still trying to decide how to efficiently load multiple items onto a delivery train and get it to where it needs to go. e.g. if I need copper and iron for electronic circuits, should I send a train to the copper furnaces first and fill half the wagon slots with copper and then go to the iron furnaces and fill the other wagon slots with iron, taking two stops and clogging up the stops for longer than necessary, or do I make a central distribution center which takes deliveries of copper and iron and then collates it properly into a "electronic circuit production facility"-specific loading train station, etc.. Just curious how you decided to solve that.

There are more options and they can be combined (some you mentioned):

1) have a car with mixed goods. You can set the train condition to leave once it has enough of each good or reserve stacks for specific items on the car.
2) have multiple cars each with one needed good (for electric circuits you could have 2 iron plate cars and 3 cooper plate cars)
3) have multiple cars with common goods on all trains (e.g. 1. car is always iron plates)
4) have multiple trains with only one good
5) make multiple stops to gather all the needed goods
6) have a central depo for each good
7) have a central depo that provides the needed good combination for each assembler type
8) single lane station with waiting bays handing multiple goods
9) station with one lane per good
10) make multiple stops to unload a single good

Option 1 works for low volume goods or if you want short trains. For example the train delivering iron ore for smelting can also bring some coal. You don't need enough coal to warrant a full car. If you have longer trains I would split goods by cars (2 or 3) or have multiple trains (4).

Option 4 and 5 mean that you have multiple trains per station. That requires a sufficient number of waiting bays or you get traffic jams. And as you grow you produce more things and have to expand the waiting bays. You probably won't leave enough space for all those waiting bays at the stations you build at the start. You always need more than you think.

Options 6 and 7 mean you can limit the (growing number of) multiple trains to one or a few locations. Put them at one side of your base and expand in the other directions at the start and you can always add more waiting bays. You also don't run into as much problems with trains going to depleted ore fields.

Option 8 has the problem that you need to balance the goods in some way so you don't end up with all of one type and nothing of the other and can't unload a train and it never leaves. Always a good idea to wait for inactivity instead of empty cargo here. On the other hand with Option 9 I would wait for cargo empty on unload.

I would choose option (4 or 5) + 6 over (1 or 2 or 3) + 7 with the exception of coal. Extending the depo for every combination of goods you need somewhere is a lot of building and hard to extend when you need more throughput. Demand for specific goods changes over time and then stations remain unused. With single good stations on the other hand you can expand the core goods a lot and have them reused for many different things. You will always needs lots of iron plates and copper plates. It's just a matter to setup the train to stop at the right places to add a new recepie. I mention coal as an exception since my depo has coal for the locomotive at each station and then it's trivial to also supply coal to a car. Make it the first car in all trains. If you do then just take care to limit the amount of coal being loaded.

I just added option 10 above. You can have one train pick up iron plates and then make multiple stops everywhere iron plates are needed. The danger here is that you run out of iron plates before you hit all the stations. But you can set the stop condition accordingly so each station gets a fair amount of items. Using inactivity as extra condition is a good idea. This can be very efficient since you can order the stations to have the shortest loop instead of having multiple trains going back and forth all the time. Good for good with variable throughput too. If one good isn't needed at the moment the next station gets more goods.

[vanatteveldt]

I don't mix trains / delivery routes, that is just too complex and station space is cheap, so a train idling in a station is fine. Moving trains should be minimized as throughput is limited, especially on core intersections / station entrances.

I have a simple system that works pretty well (except for oil trains with empty+full barrels):

- each train has one good only
- each train has only two stations (load + unload)
- all trains are set to wait until empty (unloading) and wait until either full or 30 seconds passed (loading). For ore loading they wait until the next ore train arrives (light turns yellow) so the ore station does not need a waiting bay and ore shortage at the smelter is minimized. This creates a 'backpressure' system where trains don't move unless the good they are delivering is consumed.
- each train stop accepts or gives one good only
- stations can have multiple types and have waiting bays: 1 bay just before the stop, and sufficient shared waiting bays before the branching point.
- heavy duty stations (esp. smelting) have only a single type of station (ignoring PAX and fuel) so they can have multiple trains in a waiting bay (otherwise, train type A could be stuck behind train type B)

Examples:

iron smelter ore unloading only

circuit production mixed station

[Grimakar]

I tried a similar way, but not for every item, so i summarized related items. A problem was the oil part. So I decided to make an output for plastic and sulfur (the yellow item, not sure about the exact name atm).
But finally I stopped playing this map and decided to wait for the liquid wagon.

Well, here is the map:

map

[vanatteveldt]

I tried a similar way, but not for every item, so i summarized related items. A problem was the oil part. So I decided to make an output for plastic and sulfur (the yellow item, not sure about the exact name atm).
But finally I stopped playing this map and decided to wait for the liquid wagon.

Yeah, liquids are annoying .
My refinery outputs plastic, sulfur, and rocket fuel, which is 99% of output. Lubricant is just shipped by pipe, which is annoying (but less annoying than shipping in crude to the belt factory and adding a refinery there and flaring the light+PG).
I also dislike not being able to ship water, it'd be nice to try to run my 2.5GW plant on bottled water

[mrvn]

I tried a similar way, but not for every item, so i summarized related items. A problem was the oil part. So I decided to make an output for plastic and sulfur (the yellow item, not sure about the exact name atm).
But finally I stopped playing this map and decided to wait for the liquid wagon.

Yeah, liquids are annoying .
My refinery outputs plastic, sulfur, and rocket fuel, which is 99% of output. Lubricant is just shipped by pipe, which is annoying (but less annoying than shipping in crude to the belt factory and adding a refinery there and flaring the light+PG).
I also dislike not being able to ship water, it'd be nice to try to run my 2.5GW plant on bottled water

Why ship sulfur? Are you building tons of land mines?

My only use for sulfur so far is for sulfuric acid and I have that in a pipe. A big bus of pipes shipping all the fluids. And all the fluid using things clustered close together. But maybe that's because I started with water only at the starting position so I can't produce sulfuric acid just anywhere.

PS: I really hope the upcoming fluid tanker car can be filled with any type of liquid (and gas). Would be so much nicer to ship water, heavy oil, light oil, ... to where it is needed.

[vanatteveldt]

Why ship sulfur? Are you building tons of land mines?

No, not really . In fact, I am doing a no-biter play, so no real need for mines at all

I wanted to play a train game, and ideally each 'component factory' would be connected only by train. So, sulfur is shipped to the (blue) circuits factory, the sattelite factory, the (nucular) power plant, and the store/mall.

If my calculations are correct, to launch a rocket per minute I need about 800 sulfur per minute / 1000 sulfur gas per minute (ignoring the power plant), mostly for the 100 accumulators that go into the sattelite. This could go into pipes, but piping 800 gas per minute = 120 gas per second to the sattelite would possibly require a double pipe or pumping. In any case, shipping the sulfur works fine, although it is really annoying that you need water was well to make gas.

And yes, universal barreling and/or fluid wagons would make things a lot nicer, I would much rather ship sulfur gas (and lubricant) out, it's annoying to build chemplants with the other plants...

[Grimakar]

The blue circuits is also exactly, why I ship it^^

[MeduSalem]

I don't mix trains / delivery routes, that is just too complex and station space is cheap, so a train idling in a station is fine. Moving trains should be minimized as throughput is limited, especially on core intersections / station entrances.

I have a simple system that works pretty well (except for oil trains with empty+full barrels):

[...]

Examples:

[...]

I actually have a question... Do all of your stations have loops?

Because if so then you should place both locomotives at the front to make them accelerate faster. Double-headed trains don't really benefit a train in a system where all train stations allow the trains to turn around. At least I measured once the acceleration when both locomotives are in the front and for double-headed. Double-headed accelerate slower and might not even reach max speed before slowing down again because the game is too dumb to use the horsepower of both the front and back locomotives to accelerate... instead it considered the Locomotive at the end of the train as another wagon, slowing the train down. Or did that behaviour change at some point without me noticing?



Apart from that I have thought about the idea of having a "central storage depot" which all trains deliver to and another set of trains takes from. I think that it is quite inefficient... for the reason that you basically cause more traffic on the train network since you move items around twice... from the "module" output to the depot and from the depot to a "module" input... which is more than necessary.

I might mention that I use bots only (but it could be done by belt too)... so I basically have an array of storage chests in each of my seperated "modules" (they are all seperated logistic networks). So what happens is that trains unload the resources a department needs (for example Copper Plates, Iron Plates, Plastic for Circuit Department) into active provider chests... and the Stack Inserters unloading the train are limited to a certain amount the Storage chests shall hold. Then the assemblers are also fed by robots... and for example the finished Circuits are put into Active Provider chests and the output inserters are set to a certain maximum amount of circuits which is stored into the storage chests.

So I'm kinda using a distributed storage system where stuff is stored/buffered locally at the "output" of the producing module and at the "input" of each consuming module.

Also I have a dedicated trains for each of my "modules" and its required resources. So for my Circuit Module I have one train to pick up the Iron Plates, one picks up the Copper plates and one picks up the Plastic from the providing "modules"... and then when they come back to unload they wait until they are empty before they go to pick up more. At the provider they wait until they are full or for a certain amount of time to pass so that if the provider lacks output the train doesn't block the station forever and leaves with what it has.


The only way I think that a central debot might actually work favoribly is when you use the same train to deliver resources also to move the finished output back to the depot to minimize traffic. But that would require mixed trains... and for the train to wait at the depot until all resources are ready and also at the individual departments until the shipment is fully turned into items to move them back to the central depot... otherwise you might end up with the train getting deadlocked or excess items.

[mrvn]

I actually have a question... Do all of your stations have loops?

Because if so then you should place both locomotives at the front to make them accelerate faster. Double-headed trains don't really benefit a train in a system where all train stations allow the trains to turn around. At least I measured once the acceleration when both locomotives are in the front and for double-headed. Double-headed accelerate slower and might not even reach max speed before slowing down again because the game is too dumb to use the horsepower of both the front and back locomotives to accelerate... instead it considered the Locomotive at the end of the train as another wagon, slowing the train down. Or did that behaviour change at some point without me noticing?

The second locomotive is driving backwards and automatic trains never use reverse. So the second locomotive is indeed just dead weight.

On the other hand if you only go one way then why have 2 locomotives at all? You only need that for long trains and then double headed would use 4 locomotives.

Apart from that I have thought about the idea of having a "central storage depot" which all trains deliver to and another set of trains takes from. I think that it is quite inefficient... for the reason that you basically cause more traffic on the train network since you move items around twice... from the "module" output to the depot and from the depot to a "module" input... which is more than necessary.

The idea of the depo is that you have a single point of collecting and distributing items. Consider the following: You have 20 outposts mining iron ore and 5 places where you smelt iron ore. Do you then have a train going from every outpost to every smelter (100 trains) with 4 waiting bays per mine and 20 waiting bays per smelter? Or do you have trains that stop at multiple mines or smelters? Or do you assign each mean to a smelter (4 mines per smelter)? What if some mines run dry? Now some of your smelter sit idle.

With a Depo you have 20 short trains (e.g. 1 wagon) collecting all the iron ore in one place. Then you can have 5 longer trains (e.g. 2-3 wagons) shipping that to the smelters. The ore is distributed nicely across all smelters and adding more smelters or mines or mines drying up is no big problem.

[vanatteveldt]

The second locomotive is driving backwards and automatic trains never use reverse. So the second locomotive is indeed just dead weight.

On the other hand if you only go one way then why have 2 locomotives at all? You only need that for long trains and then double headed would use 4 locomotives.

Sorry if I was unclear, both locs are pointing in the same direction. The reason for having the second loc behind the wagons is that is also allows stations to be used by single-loc trains, I usually start with LCC or LCCCC and then upgrade to LCCCCL.

I think a depot could work well for 'multiplexing', ie if you have n:m situations. I would just have two completely separate stations, one for loading and one for unloading. That prevents the bottleneck on station entrance, and you can probably separate the traffic flows (i.e. one network that goes only outposts -> depot, on network depot -> smelters(+refinery), and one network smelters -> factories.

OTOH,is having multiple smelters ever more efficient than a single large smelter? Or would you keep the flows separate behind the smelter, i.e. a smelter dedicated to the circuit factory, and another smelter that delivers to the LDS factory, etc?

[MeduSalem]

Well lets get the SIngle-headed vs Double-headed train and 2 locomotives stuff out of the way right away...

On the other hand if you only go one way then why have 2 locomotives at all? You only need that for long trains and then double headed would use 4 locomotives.

Increased acceleration speed... the trains leave the station faster, reach top speed faster... hence spend less time on the train network... increasing overall maximum possible throughput on the network.

But that said I never use double-headed trains because I don't have terminal stations where the trains would have to leave in reverse. I find that kind of stuff pretty ugly, especially if I have to make a mixed train for some unforseen reason... then all of a sudden the train has to be symmetrical or otherwise the loading/unloading freaks out, which is just not worth the trouble.

So I used to have loops before/after each station to make the single-headed train turn around... similar to vanatteveldt's pictures show. That said in newer games I'm experimenting around with all kinds of modular-grid/mesh-based networks too... so it's not a star network or real bus network anymore because both suffer bottleneck problems.

Sorry if I was unclear, both locs are pointing in the same direction. The reason for having the second loc behind the wagons is that is also allows stations to be used by single-loc trains, I usually start with LCC or LCCCC and then upgrade to LCCCCL.

And that works? I didn't know that <LCCCC<L is even working. I thought to profit from two locomotives pointing in the same direction for increased acceleration speed they both have to be at the front like <L<LCCCC.



Now on to the Depot stuff:

The idea of the depo is that you have a single point of collecting and distributing items. Consider the following: You have 20 outposts mining iron ore and 5 places where you smelt iron ore. Do you then have a train going from every outpost to every smelter (100 trains) with 4 waiting bays per mine and 20 waiting bays per smelter? Or do you have trains that stop at multiple mines or smelters? Or do you assign each mean to a smelter (4 mines per smelter)? What if some mines run dry? Now some of your smelter sit idle.

With a Depo you have 20 short trains (e.g. 1 wagon) collecting all the iron ore in one place. Then you can have 5 longer trains (e.g. 2-3 wagons) shipping that to the smelters. The ore is distributed nicely across all smelters and adding more smelters or mines or mines drying up is no big problem.

I think a depot could work well for 'multiplexing', ie if you have n:m situations. I would just have two completely separate stations, one for loading and one for unloading. That prevents the bottleneck on station entrance, and you can probably separate the traffic flows (i.e. one network that goes only outposts -> depot, on network depot -> smelters(+refinery), and one network smelters -> factories.

OTOH,is having multiple smelters ever more efficient than a single large smelter? Or would you keep the flows separate behind the smelter, i.e. a smelter dedicated to the circuit factory, and another smelter that delivers to the LDS factory, etc?

Okay, well I don't have 5 different places to smelt ore... I usually have one huge smelting plant that in its current form could be upgraded to smelt somewhere about 40-50k Units/Minute of Iron Ore or Copper Ore, if not more. Basically a smart furnace that divides the smelting capacity proportionally between the demand of Iron Plates and Copper Plates. The throughput is so ridiculous that I haven't run into any bottlenecks yet in my previous games... so I never really had the urge to further upgrade it.

So basically all Ore outposts unload their ore at that one smelter... and on the load side all trains for the various other departments come here to pick up their Iron Plates and/or Copper Plates.


That said with "central depot" I actually meant one central depot that handles ALL items/resources the game has... like a central interchange/multiplexer that does the collection and distribution of all items and resources of the entire base (of course using bots to load/unload trains and store the items in that depot, otherwise it would not be feasible)... and I think that would be problematic. Though I have some ideas on how one could make it work without crossing a single rail track. If the idea turns out well I think it would be the most ridiculous thing one has ever done with trains in Factorio.

[vanatteveldt]

Sorry if I was unclear, both locs are pointing in the same direction. The reason for having the second loc behind the wagons is that is also allows stations to be used by single-loc trains, I usually start with LCC or LCCCC and then upgrade to LCCCCL.

And that works? I didn't know that <LCCCC<L is even working. I thought to profit from two locomotives pointing in the same direction for increased acceleration speed they both have to be at the front like <L<LCCCC.

I supe assumed so :-S.

Let's science this!

Setup: long loop with two stations A and B, train at A set to go to B (wait 0 seconds) and back to A. Inserter connected to a traffic light before stop A set to insert from a creative chest if light = green. So, it will insert as long as the train is gone, so more items in the chest = more time = slower train

experimental setup

setup blueprint

Code: Select all

H4sIAAAAAAAA/52a726iTBSHb6XhszRFQW0a3ht5szEsjHYSBDOMZg3x3heQ00Vt1vPst7Y858cwv/lz5kyL+qWs86x82aStqbz11jRp21bZ3qRBfnQnU4Qu
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1/3wfcQc9EtdFWP81rrGS0e0/nzoXneyzh/77h/bOjwMh74Ihn5qfFb59K37cX/IXOY77eC/4KLuw+R96MLrZ/UXwLYqTPcl4wuz0poqzJy32yz3wYWMOrAm
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nPFHV71sPkxV/AbLe2oAkiAAAA==

(all trials done twice, but identical counts, so I think it's deterministic)

Results: (lower=faster)

LCCCC = 114 items
LLCCCC = 90 items
<LCCCC<L = 90 items (i.e. two locs back and front, both pointing forward)
<LCCCCL> = 129 items (i.e. two locs back and front, each pointing outward)

As expected, a second loc pointing backwards is dead weight and slows down the train, but for locs pointing forward it doesn't matter if they are at front or at back, i.e. they push as well as they pull. A CCCCLL (with both locs pushing) works as well as a LCCCCL or LLCCCC design, as long as all locomotives point in the direction of travel.

So: yes, it works

[vanatteveldt]

That said with "central depot" I actually meant one central depot that handles ALL items/resources the game has... like a central interchange/multiplexer that does the collection and distribution of all items and resources of the entire base (of course using bots to load/unload trains and store the items in that depot, otherwise it would not be feasible)... and I think that would be problematic. Though I have some ideas on how one could make it work without crossing a single rail track. If the idea turns out well I think it would be the most ridiculous thing one has ever done with trains in Factorio.

Now that just sounds crazy . I think the point to optimizing train traffic in factorio (especially given the lack of overpasses/tunnels) is to separate flow as much as possible, i.e. separate lines for ores, plates, etc.

If you have a central storage but with unconnected rail systems, you essentially have a bunch of good-specific depots just placed close together, right?I.e. you could also pull them apart and it would function exactly the same.

But my question would be: what is the point of such as 'depot'? I always have only one place producing a certain good, so that place is essentially the 'depot' of that good. If you add a depot without adding more places that produce it, you just add an extra train trip without obvious benefit, especially since the number of loading bays for a good at the production facility and at the depot need to be identical or the production->depot line will be the bottleneck... or am I missing something?