This is the Roundabout blueprint for my rails blueprints.

The Roundabout is the only intersection needed.

About these rails:

• These rails are grid aligned and chunk aligned, which means that if you connect them correctly, they will always end up aligned to another end of a rail and connect perfectly. Even if you make an entire rails network around the map and connect both ends, they will align.
• All you need to do is lay the blueprint and connect the endings of the rails to the next one.
• The rails are made to support trains of a maximum of 4 length; 1 locomotive + 3 freight cars. More than that and you introduce the probability of a deadlock.
• The rails also have signals at perfect intervals to prevent deadlocks or gridlocks. The only way to get a lock, is if you have more trains than your entire network can support.
• Each blueprint uses the MK5 blueprint from https://ficsit.app/mod/KBlueprintDesignPlus, that's if you want to edit them.