Multiple Trains vs Bigger Trains?

[theorderofthings]

I see a lot of posts on here about different junctions and signalling issues for complicated train networks where there are many different trains going on the same track.

What I'm confused about is the purpose of complicated train networks. I understand that you may want junctions and whatnot if you have different rail lines intersecting with each other, but why would you want many different trains on the same track? Wouldn't it usually make more sense to just increase the size of the train if you want more throughput? When would it be better to have multiple rails and stackers rather than having a bigger train with more locomotives?

[Kelderek]

Managing trains and tracks are a huge source of fun in this game for many, so a lot of it comes down to personal preference. Smaller trains are often faster on the track, larger trains may take much longer to load and unload. I think the important element is to design your entire rail network from the start using a planned max train size. Most of the problems I often see on the forum are due to poor planning: too many stations in a small area makes for high congestion, trains too big for the amount of rail provided, not enough bays for waiting trains, etc.

Plan for the largest size train in your system, but not all trains have to be that long. A rail network that can handle 2-4-2 can also handle 1-2-1. The longest trains are usually for the simplest materials like ore, more advanced items can be handled by shorter trains. It's easy to downsize a train, but it's harder to make a train network function for a new larger train size. So if you are 40 hours into your game and your largest train was 1-2-1, but now you decide you want some 2-4-2 trains, there is a good chance that your network of rails will need a major overhaul to handle that kind of change.

There are many benefits to larger trains, but that comes at an increased setup cost (they need larger loading and unloading setups). I personally have never gone bigger than 2-4-2, I've never felt it was necessary. Many of my trains that size take a very long time to fill up so if I went much bigger there would be exceedingly long gaps between train trips and that may cause problems for throughput of goods. I imagine trains larger than that would be useful for mega-bases only.

[5thHorseman]

That's a great answer, but I'd like to expand on one part of it.

A rail network that can handle 2-4-2 can also handle 1-2-1.

The cool thing about this is you can set up a station to unload from the 2nd spot (the first being the engine) only coal, and then have a coal train that services every station. And then you can also set up a personal supply train that also just fills up that second slot, and have it go around and drop supplies locally so bots can refill you wherever you are. Of course, you can do this anyway but if your stations support 2-x trains and 1-x trains the 1-x trains won't step on the toes of the 2-x trains because they unload in the third slot and beyond.

Personally I like 2-4 and 1-2 trains (so they only can go one way), but have never mixed them in the same game. I may make my next game have both of those along with some 1-1 coal and supply trains.

[Mr. Tact]

Personally I like 2-4 and 1-2 trains

Me too. Although unlike you I do mix on the same map, Generally I use 2-4 trains for ore or plates and 1-2 trains for oil, or any other fluid. I also prefer barrels of oil over using tankers. I was very happy to see the addition of barreling for all the fluids. The exception is Uranium, for that I use a 1-3, two cargo wagons for ore, one with a 50/50 split of reserved slots for empty barrels and barrels of sulfuric acid.

[AndrewIRL]

When would it be better to have multiple rails and stackers rather than having a bigger train with more locomotives?

I don't personally build them so this is speculation but Megabases would require multiple trains. They consume so many resources that you need to be simultaneously mining multiple ore patches of the same kind, maybe 5-10 iron ore, 3-4 copper ore, 5-10 coal etc. If you have one giant train that visits all ore patches then it would take a long time to complete a round trip and your factory would need giant buffers. Smaller, more frequent deliveries can keep the factory going so one train per ore patch. The trains fill fairly regularly and return to the factory at essentially random times and they need to be kept from jamming the track so you need stackers and high throughput junctions to run. That's just for the mined resources, huge factories will probably put some partially finished goods on trains too.

In my non-MegaBase I run one train per mining location. If I had 20 mining locations I'd need 20 trains.

[theorderofthings]

There are many benefits to larger trains, but that comes at an increased setup cost (they need larger loading and unloading setups).

But isn't the setup cost decreased in a lot of ways? If you use 1 very large train, for example, you don't need stackers and can even use only one lane of rail with a double-header. Sure the startup cost may be a bit higher, but overall you are going to be using way less track and way less signals. When you start adding multiple trains you need at least two lanes for going back and forth, different types of junctions, stackers, et cetera. Wouldn't it make a lot more sense to use something ridiculous like a 10-20-10 train rather than 10 1-2-1 trains? Although, I don't know which one would be more fun. And if you aren't building stackers and only a few junctions, it's very easy to expand a 10-20-10 train into a 15-30-15 train.

Of course, you probably want to use at least a few different trains, for different ore types, but it still holds that your infrastructure is much easier, since you don't have to handle so many different trains. And if you want to be especially efficient at the cost of functionality, you could be different ore types on completely different train networks.

In my non-MegaBase I run one train per mining location. If I had 20 mining locations I'd need 20 trains.

This makes sense, although it would probably be less of a problem with RSO.

[Kelderek]

If you use one train for multiple types of cargo that adds a layer of complexity that many people don't want to deal with. I design my trains so that ALL of them only have one kind of cargo, the main exception to this is a defense supply train that brings things like turrets, walls, ammo, repair packs, and construction bots to my various fortified positions.

You can also end up with a large train rail network and lots of trains if you choose to de-centralize your factory. In my current game I have designed it so that I have a separate outpost to make each science pack. This results in me needing far fewer resources at my main starter base, but I now have to deliver resources to each of those outposts. As an example, my high tech science outpost has trains that come in to deliver plastic, iron plates, copper plates, sulfuric acid and solid fuel (to refuel at all these train stops), and I have one train that departs this outpost to deliver finished yellow science packs back to my main starter base that has all the labs in one place. This outpost makes all the items needed for the yellow science packs, from copper cables to all three circuit types (green, red, blue), speed modules and batteries.

With this setup I have trains that need to deliver iron plates, for example, from many mining outposts (where I smelt it on site) to many production outposts, so I have a busy train system with lots of trains with a max size of 2-4-2. There's a lot going on, but it is fun as hell.

But isn't the setup cost decreased in a lot of ways? If you use 1 very large train, for example, you don't need stackers and can even use only one lane of rail with a double-header. Sure the startup cost may be a bit higher, but overall you are going to be using way less track and way less signals. When you start adding multiple trains you need at least two lanes for going back and forth, different types of junctions, stackers, et cetera. Wouldn't it make a lot more sense to use something ridiculous like a 10-20-10 train rather than 10 1-2-1 trains? Although, I don't know which one would be more fun. And if you aren't building stackers and only a few junctions, it's very easy to expand a 10-20-10 train into a 15-30-15 train..

It's a question of scale. Even with huge trains you will still need stackers once the throughput needs get high enough. Even with as few as two trains you might need to have two lanes to ensure decent throughput. I run a map with 40+ trains. I need that many trains because I have so many train stops and a large variety of train routes that are needed. You simply cannot cover that amount of variation with only a few trains and have it function smoothly and quickly enough to have decent supply and demand satisfaction.

Some might find a large network of trains to be a pain and messy, but I find it to be one of the most fun challenges in this game and I enjoy every minute I spend working on my trains.

[vanatteveldt]

I admit that I enjoy playing with trains too . I hate main bus bases, I generally divide my factory into smaller units and have train connections between the units. Right now I'm doing a no-belt base, with local roboport networks and long-distance train connections.

I use stackers/waiting bays and multiple trains for two reaons:

1) Ore to smelter: Many different ore outpost send ore to one smelter, and I want to have at least two trains per outpost: they are set to wait until empty at smelter, and wait until full OR red>0 at the outpost. I think connect the signal before the station signal to the station, so if the next train approaches the currently loading one goes to the smelter. That way, trains only depart with half loads if the other train was emptied out before the train at the outpost could be fully loaded. With 5 outposts, this means 10 trains for a single smelter.

2) Intermediate products (e.g. plates, circuits) to production plants. Here the relation is reversed: one producer (e.g. the green circuit plant) sends to many consumers. Each consumer gets at least one train set to wait until empty. At the producer they are set to wait until full OR 30 seconds OR there is no more produce to pick up. This means that the producer plant needs to have loading+waiting bays equal to the amount of consumer trains.

It is usually a good idea to try to keep separate networks separate. I currently have the ore -> smelter network configured for single header 2-4 trains (to maximize throughput), and the rest of the network for 1-2-1 double header trains (for more compact stations and junctions).

[iceman_1212]

another reason is practicality. in theory, i could indeed replace my network of ~150 1-4-1 trains with one train that has 600 wagons on a single looped track that runs through all stations but that would be kind of a PITA to setup and manage.

once the fundamentals of a train network are in place (i.e., blueprints for straight track, junction, stacker and station), it is extremely easy to add outposts and train in plug & play manner.

[theorderofthings]

another reason is practicality. in theory, i could indeed replace my network of ~150 1-4-1 trains with one train that has 600 wagons on a single looped track that runs through all stations but that would be kind of a PITA to setup and manage.

once the fundamentals of a train network are in place (i.e., blueprints for straight track, junction, stacker and station), it is extremely easy to add outposts and train in plug & play manner.

Hmm... it seems like the best answer is a comprise - just have ~150 600 wagon trains!

[iceman_1212]

[SpeedDaemon]

Bigger trains require more space - bigger stations, more track between intersections, etc. Trying to build that infrastructure in/around existing bases can be more difficult.

Regarding stackers/parking: I will always have enough parking before a station to accommodate every single train that uses that station showing up at once without blocking the main line. This is the primary reason you have stacker areas.

Big trains work well for long hauls (outlying mines -> smelting/ore xfer) because it doesn't matter if they're slow, and there's usually plenty of space. Within the main area of my base, I usually use 1-3-0 or 1-2-1 max for speed/space reasons (and I usually just don't need anything bigger for finished products).