Getting your 4 to 3 balancer factorio layouts right
If you've spent any time at all scaling up your production, you've probably realized that a 4 to 3 balancer factorio setup is basically inevitable once you start moving past the "spaghetti" phase of your base. It's one of those weird middle-ground configurations where you aren't quite at the massive 8-lane highway level yet, but you've definitely outgrown your humble starter lines. Usually, it happens because you've got four lanes of copper or iron coming off a smelting array, but the sub-factory you're building only needs three belts to stay saturated. ...