Source
r/factorio•
linzefeng

Train grids with one-way roads?(not one-way rails but one-way multi-lane rail systems)

Discussion

so i am building a new mega base using the common train grid style, where there is a 6 lane ( 3 lane for each direction) grid of rail highways, and with manufacturing blocks attached onto the high way. However, i noticed that there will always be a big bottleneck at the intersections in the grids, and scaling up the number of lanes have diminishing returns unless i use a very optimized but absolutely massive intersection like this http://i.imgur.com/zVUdQ4I.png. so i came up with a rail grid that only allows one way traffic, with each block cycling rotation like this

https://i.redd.it/7edqy2iwlsi21.png

this should allow much simpler and more efficient intersections, but also means that trains on average have to travel further to reach their destinations.

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How well would a system like this work? has something like this been done before? I'm curious what you guys have to say.

Posted Feb 25, 2019, 10:45 PM UTC

622
xaphod•

Are you me?! I was just thinking today about this same idea on my break at work, with similar drawings.

https://imgur.com/96wK6aA

3
xaphod•

Also thinking about just using multiple lanes going in one direction on the "highways" as well. They'll just need to do big loops. Crossing intersections seem to be the biggest problem with trains so why not to avoid them completely?

2
linzefengOP•

so the entire train net work would just be one huge one way loop? interesting

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2
xaphod•

Not just one loop, because it would be difficult to expand that and trains would need to go all around to reach a near station "upstream". It could have smaller loops inside it, but all going the same direction so there are no crossing intersections, only merging and splitting.

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I know this is probably not a novel idea. I'm currently just trying to build my first megabase with trains and hitting some bad train issues with loads of trains waiting in intersections and i don't even have that big of a production yet, just mass producing green+red+blue cards and tier 3 modules at this point.

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2
linzefengOP•

nice! guess i wasnt the only one. im looking at at your layout, and it looks like it might be better! the routes would be shorter and the intersections are also simple.

i have built a intersection for my layout if u are interested https://media.discordapp.net/attachments/308287109398134784/549387172696817675/unknown.png?width=1202&height=677

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2
G_Morgan•

Can you switch lanes at an intersection here? It is hard to see.

1
linzefengOP•

nope

1
G_Morgan•

I've never understood the value of multiple lanes without lane switching. How do you balance load across the rails?

2
linzefengOP•

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i just made a intersection with your layout

2
Dysan27•

What that orange thing that looks like a portal ring to the right of your character?

1
linzefengOP•

yeah its a portal from the portal gun mod

1
G_Morgan•

Can you put a belt through the portals?

1
knighteliteLTN in Vanilla guy. Ask me about trains!•

I made one with that type of grid, but the "intersections" were actually in the middle of the parallel tracks on each side of the grid. It worked OK, but I quit playing that game due to expanding through biters becoming tedious.

Regarding the base layout itself, I have a couple notes:

  • Riding automated trains from one place to another was fine, but manually driving trains was extremely tedious due to being unable to drive straight. Many wrong paths were taken doing that until I just started riding automatic trains only.
  • I highly recommend including red + green circuit wire into your blueprints block blueprints. I updated my blueprint partway through to add that, and had to manually add it into the older part of my base.
  • You will need two different grid square blueprints (one for clockwise and one for counter clockwise). Try not to accidentally put two clockwise ones next to each other or you will have to rip it up. Not sure what size grid you're going for, but in my case the blueprint for a fully tileable 2x2 grid was too large to place easily and line up with the rest of the grid, so I had to do each grid square independently.
2
xaphod•

How can you manually drive anywhere anyway when there are automated trains running? I always end up crashing when I try to do that.

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2
knighteliteLTN in Vanilla guy. Ask me about trains!•

I did a fair bit of crashing too :). It was mostly done when I was driving around as yet unfilled-in grid squares with my train full of construction supplies. I later switched to renaming one of the stations (which were included in the blueprint) to "build" and just telling the train to go there.

2
linzefengOP•

i have several qol mods that helps with building planning and getting around, so that wont be an issue, but i am curious what you use the wires for. i have tried doing dynamic train systems that adds train/enables station on demand but it seems really involved.

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2
knighteliteLTN in Vanilla guy. Ask me about trains!•

That's basically what I was doing. Something similar to Haphollas train network.

1
excessionozPlaying 0.17.x•

I worked with a friend on such a 'one way' City Block system.

We had lots of experience with an omnidirectional four track City Block system, but found out that train chaos arose due to random causes, and could take ages to untangle.

The culprits were the high-traffic areas.

Moving the high traffic areas away from each other, spreading out the load on the network, made the network more effective, but reduced the overall efficiency of the factory.

Going to a one-way system had a heap of associated problems, since putting city blocks with one way systems next to each other, ended up with gridlock immediately. When your track infrastructure is part of the city block design, you needed to have a number of city block blueprints, with different signalling options to enable smooth interchange of traffic -- and it was a pure nightmare to implement.

With the 'old' omnidirectional scheme, adding city blocks was simple.

The payoff came when we were able to run more than 270 concurrent trains on our map, compared to failure/chaos at around 140+ trains on previous maps. Eventually we had pragmatic 'popular destinations' stackers to take care of the 'trains parking on the main lines' problem(s), as trains stacked up waiting for access to load/unload resources.

TL;DR always have stackers available around the popular 'destinations' on your map, so that high traffic areas always have somewhere for trains to park, no matter how many trains are using that quadrant of the map. This means if you nave a quadrant with 9 stations and 40 trains heading there, you need a stacker that can cope with at least 90% of those 40 trains, if they were to arrive concurrently. Such stackers take up a lot of real-estate.

Good luck with you network.

2
linzefengOP•

i have an old 1kspm base that used 4 lane bidirectional grids that had 250+ 1-4 trains, had no problems with grid locks since all stations with more than one train assigned to it have a corresponding stacker. most of the train traffic in the grid came from ore trains, so with the new base im trying to isolate them into a separate system.

congestion is actually pretty low, and building it was also simple, with 1 intersection blueprint, 1 straight section bp, 1 branch off bp, 4 diff station bp and 1 stacker bp was enough to build it. but if i would try to scale that to 5kspm it would defiantly not hold out even if i added more lanes.

1
excessionozPlaying 0.17.x•

My friend and I were haphazard with our placement of tracks around the base, and had sub-optimal major routes. I do not have the patience/skill to construct factories that are completely free of defects :).

1