How it works
Build a two-station train line and expand it into a safe, signal-aware network. Each stage in the walkthrough below has a distinct practical objective; complete the current supply or control loop before expanding it.
Practical advice
Put rails, locomotive, cargo wagon and station positions into a complete path. Check locomotive direction, fuel and the schedule before trying any junctions.
Mistakes to avoid
Never assume an unrelated blueprint or another version of Factorio has identical recipes, technology unlocks or machine ratios. Use the checkpoints in this guide to diagnose your own save.
Trains, rail signals and deadlocks: complete walkthrough
Construct a reliable basic route
Put rails, locomotive, cargo wagon and station positions into a complete path. Check locomotive direction, fuel and the schedule before trying any junctions.
Learn rail blocks
Rail signals divide track into occupied segments. A standard signal can permit entry when its next block is free, but should not allow a train to enter a junction with no usable exit.
Protect intersections
Use chain signals where you want to reserve a clear path through a junction and rail signals afterward, adapting the common rule to actual block geometry.
Schedule stations
Define loading and unloading objectives and choose waiting conditions that can realistically become true. Use station train limits to prevent unsafe queues.
Debug congestion
Inspect the path visualization, junction occupancy and train length. If trains wait permanently, verify there is a valid route and that no downstream blocks trap them.