Lock Bullets Settlement For Free

The best defensive setup I've found is walls. Lots of walls. If you can funnel attackers to one or two entrances you can lay down multiple tiers of turrets to take care of them. As for turrets, the basic turrets are ok against light raiders but against heavier attackers like death claws you'll want the bigger stuff.

Locking doors in settlement Open console. Click on the door you wish to lock. type "lock 1"

The best defense for settlements are turrets and the settlers themselves. Arm the settlers with good weapons that you won't be using. combat rifles, assault rifles or miniguns. Give the settler a single bullet for their weapon and they will shoot forever.

Nevertheless, defense stat must be equal or greater than food plus water otherwise the settlement will slowly get unhappy. It means if you have, e.g., 20 food and 880 water, you'll need at least 900 defense for happiness not to decrease. This is my understanding as well. Also the chance to get attack is a base 2%.

Build up your defense to be double the combination of water and food. EXAMPLE: If your settlement has 20 food and 20 water, make defense over 40. This will reduce or stop raids on your settlement.

Each settlement needs the numbers next to food and water to be higher than the number of settlers who live there. To increase your food supply, plant crops and assign settlers to manage them. For water, build a few water pumps or ? if the settlement is on the coast or contains a large puddle ? a water purifier.

Settlements can defend themselves successfully but its really low chances to do so. Its like this: defense must be equal to or higher than food+water total. That only lowers chances of getting raided. There is no 100% way to not get raided.