The Feasibility of Outpost Building Trains

[mrt144]

So I am getting into the main course of my megabase build and I realized that I hate manually doing most construction. Love using construction bots to lay down blue prints once I finalize the blue print. One idea I that popped into mind was creating a specific train carrying all the components I would reasonably need to accomplish any remote extraction/production build.

In my game I have a 'Factory of Things' - basically if you can craft it, this factory makes it plus some. Construction Bots, Logistic Bots, Speed Modules, Railroad tracks, Roboports etc etc. So the idea is to lay track to the destination, set up a stop and then have a train carrying all manner of goods arrive at the stop and unload the building materials. Building materials are picked up from passive provider chests at the drop off station and put where they need to go by the construction bots.

So there is a lot of labor in track laying and power manually because by and large making a replicating blueprint with roboports to lay tracks over and over will prove cumbersome and power intensive. I've already tested the limits of how far construction robots can venture before I become impatient in waiting for them to show up and just manually plop down what I specified.

Material Pickup Station consists of request chests requesting all possible products to load onto the train in reasonable amounts. This includes both construction robots and logistic robots (like for nuclear power operation, I just like how easy the logistic robots make everything at the reactor stage.)

So working through a lot of this in my mind the biggest stumbling block comes down to the requester chest to train transfer. I'm struggling to find a theoretical way to have the train cars loaded with a multiple differing goods to a specific amount onto the same train. Example would be I want one train car to have 1000x Blue Track 500x Fast Loaders, 100x Power Poles. And not to overfill based on the amount of slots available on the train car.

So basically is there a way to do an item count on a train and link it to the inserters loading the train so that they turn off once they've filled the quota on the train car that I desire. I haven't been able to dive into this hands on because I'm on a business trip and just got into building my train depot before I left but my noodle is racing on solving this before I get back home.

Would one work around be to create a steel buffer chest that gets fully loaded to the quota I specify and then shuts off the requester chest inserter behind it and then turns on the loading inserter to the train until the steel chest is depleted? Is there an even simpler way than that?

[Zavian]

There are a number of ways of loading construction trains. The simplest is to filter the cargo wagon(s). Then have 12 inserters each loading one item from a requester chest. (If you use long handed inserters you can double that to 24 items/wagon). You can also do more complicated setups with combinators, but for me the simpler setup meets all my needs, and is trivial to build and debug.

For building rail blueprints I normally sit in the lead locomotive of the construction train, crawl forward with the train, and use my personal construction bots, then top-up my inventory from the train as needed.

There are also mods that add equipment grids to trains, and even a mod that automates rail building (https://mods.factorio.com/mods/Choumiko/FARL)

[Greybeard_LXI]

Zavian has the easiest answer.

One way to tweak it a bit is to use one chest and an inserter with stack size 1 for stuff you do not need much of that have small stack sizes like train stations, roboports and chemical plants.

[aober93]

You will need material to build the material request in the first place. That and the rails leading to it.
If you have that, you can bring all the other items as well. Typically in one large train.

I have tried it, but i didnt stick with it.

[Aeternus]

I use builder trains almost exclusively to build stuff in larger games. Draw a rail to target location, optionally power. Plop a station with a predetermined name. Wait for builder materials train to arrive while your roboport already clears the terrain (and call a second garbage disposal train to get rid of wood, stone, coal etc). Some tips and tricks:
- You typically won't use the builder trains with great frequency. Load speed thus isn't an issue.
- They'll use a wide variety of goods. Belt loading is not practical, this should be a logistics grid job.
- If you have a wagon which uses a low volume of multiple items, you can use a single requestor chest to load those from to save space (think splitters, combinators, speakers - stuff you would only use one stack of). If so, make sure you set the inserter for those to a stack size of one to prevent them from getting blocked.
- Having some raw materials available can sometimes be a plus. Add a stack of iron, steel, copper etc.
- Outpost building and factory building are different jobs. Use different trains!
- Also make sure you have a garbage disposal train standing by to bring a decommissioned outpost back to your factory. Buffer chests are great for only producing goods on demand in a structure factory (example: Buffer chest requests 2000 electric mines, inserter from mine producing assembler is set to work if the amount of mines in that chest is below 100)

[vanatteveldt]

What I've done in some games is to have one general "bootstrap" building train, and then multiple trains for different construction types (e.g. outpost, smelting, etc)

The bootstrap train is the train I use for setting up new outposts or plants. It contains a *lot* of rails, and some chests, inserters, conbots, roboports etc. Idea is to go somewhere, place the (e.g.) "outpost starter" blueprint, which is built from materials in the train and my inventory. This outpost starter contains just enough to get started on automatic construction: an unloading station for the builder train, a roboport, and logistic chests to unload needed goods from the builder train (and a radar to keep visibility).

The unloading station automatically calls the builder train and is disabled if there are plenty of supplies (mines, more bots, more roboports, belts, inserters, etc - everything needed to build your outpost).

Then, you can leave the site and add blueprints for building/expanding the outpost as needed. The resident conbots will build it, and call the builder train if more supplies are needed. Sometimes the train needs multiple runs, but who cares? As long as it's done the next time you look...

This was a no-biter game, otherwise of course include defensive stuff as well, and/or have a second 'supplies' train to bring ammo, oil, etc.