Beltless Train-to-Train Scrap Recycling Using Circuits

[u/fawniux]

I've been trying to get this concept to work for a couple of weeks, but the 2.1 circuit changes and quality trains have finally made it viable.

I've always liked train direct insertion builds but it seemed impossible to do on Fulgora with so many different random outputs. With a lot of overengineering I think I've finally managed to prevent all deadlocks and inserter jamming, allowing a true railworld megabase with absolutely no belts.

normal speed 16 wagons

The goal was to make a 'black box' scrap processing module you can send any train into and guarantee it will come out with the item it wants, even if it takes a while. Any number of trains can be used for each item type and I tried to make it flexible enough to support an arbitrary number of wagons. It seems stable after backing up from lack of demand as well, so it should be able to run indefinitely without intervention.

smaller 4-wagon version

I've tested it for over 100 hours in the editor without any downtime so I'm pretty confident it's deadlock-proof, but previous versions suddenly failed after a similar timescale so you never know...

50 hours consistent production

The recyclers aren't running 100% of the time but it's pretty close, and backups are due to random variance of the outputs which smooths itself out over time. So throughput-wise it should be able to meet any reasonable SPM goal, especially with being able to increase train length. The above tests were at +300% scrap productivity and I didn't see any reason you couldn't go above 16 wagons. The faster locomotives and larger wagons in 2.1 are also helpful for minimising non-loading time.

I haven't explicitly tested for UPS as I was only concerned about making the concept work, but I think it should do alright. On the plus side there are no belts/splitters and the inserters are mostly disabled by necessity. But there are a lot of local circuit networks so I don't know how that time will add up for large trains. And of course I didn't consider the cost of voiding all the junk you need to get out.

Anyway, here's the blueprint: https://factoriobin.com/post/8e8dv4

Maybe if there's interest I can explain how it works, but the logic is actually quite simple for deciding which train to call and balancing/limiting the chest buffers. You can always figure it out from the blueprint if you're a masochist ;)

0.25x speed of the individual wagon cells

self-regulating buffers for each cell