How Perfect Rail Networks Work [Factorio]

comfy train in snowy japan

In this post I will show you the principles behind building rail networks in Factorio, so that you understand what you’re doing before you do it, you understand the problems when they appear, and, if no mistakes occur, you create networks that never jam ever.

“Contributors are instructed: “Wikipedia is an encyclopedic reference, not an instruction manual, guidebook, or textbook. Wikipedia articles should not read like … instruction manuals. ”

When I look something up related to computer science, it is normally because I am working on a project, and need to know how to do something, so I need something that reads like an instruction manual, guidebook, or textbook. Further, anyone who knows computer science stuff is usually an engineer, so is apt to write like a textbook or instruction manual. The effect and application of the not-a-manual rule is to prohibit contributions from people who actually do stuff, which contributions they intend to share with other people who actually do stuff, in favor of contributions by people who do not do stuff, and are incapable of doing stuff – which is to say, in favor of academic knowledge.

– Jim

  • Game version: 0.15.37
  • Current number of hours played: 89
  • Longest game in hours: 30
  • Total games played: 1 regular, 2 deathworld
  • Total games completed: 0
  • Time spent figuring out rail theory in hours: 6
  • Amount of notes: 1 8.5×11″, 2 5000x5000px
  • Number of perfect rail networks made: 1

I am writing this because all other explanations I’ve found were insufficient.

They’re either video tutorials, which are too long and too slow so they don’t matter, or they’re image and text guides, in which case all the ones I’ve seen had their priorities completely backwards. Like a bad and uninteresting class they spend all their time going over jargon and then straight into generic concepts everyone could’ve figured out beforehand, and none at all on basic principles and thus are not applicable to truly useful examples. They even provide you with blueprint strings so you’ll be even more sure you’re right while being even more confused if something goes wrong.

It’s confidence in the wrong place. Which leads to the expected result, results you may have seen: big-time youtubers with blueprint books of huge pre-planned intersections and stations, all auto-built with construction robots, only to run into a jam that they run halfway across the map to fix manually. And they’ll do it again. And again. Every handful of minutes.

The problem with these guides is they emphasize signals. They’re trying to properly signal intersections. All their planning and corrections are based off of placing signals correctly.

They’re not trying to build a rail network.

This isn’t a matter of being pedantic: “If all you have is a hammer, everything looks like a nail”. The point of a rail network is to have trains running properly, not to have signals running properly. The signals will always run properly. The question is do they run in such a way that your network runs properly. It is about the rail network’s purpose first, then about rail placement, and only at the end do signals come into play. Things must be thought about in that order: Network first, rails second, finally signals.

Approaching rail networks with that mindset clears all obstacles.

> Let’s Look at Networks
> Think in Blocks, not Signals
> What a Signal Means
> When, or Why to Upgrade to Dual Rails
> General Principles, Summarized
> Specific Applications

> — Intersections (3-way, 4-way)
> — Train Stations
> — Personal Trains
> The Blue Signal, Revisited
> References / Other Rulesets

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