- 1). The lock will go on the edge of your door, where the door slides into the door jamb. Place the lock into the place it will go and mark where on the sill the lock will hit.
- 2). With the patio door closed, drill through the metal door frame and the metal that holds the glass in. Match your bit to the size of the lock bolt. The bit should be slightly larger than the bolt.
- 3). Open the door and place the lock where you had it earlier. Using a small bit, drill pilot holes for the metal screws to attach the lock to the door track.
- 4). Screw the lock apparatus to the floor. Close the door and make sure the bolt slides neatly through the hole and keeps the door closed.
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