How to Use Galvanized Posts for Picket Fencing

Mark the first corner post in two places, where you intend to position the lower edges of the horizontal rails. Tie a string to the first post at the top mark. Extend the string to the next corner post. Hang a line level on the string. Pull the string taut, then level the line and tie it to the next corner post. Mark the posts between the corner posts where the string crosses them. Repeat to mark the positions of the lower rails on the fence posts. Remove the strings.

Remove the bolts on the U-shaped clamps on the fence adapters. Place two adapters on each post. Replace the bolts, but do not tighten. Position the upper adapter so the lower edge of the shelf is aligned to the upper mark on the post. Orient the adapter so the shelf faces the side of the fence where the pickets will be installed. Use a socket wrench to tighten the clamp onto the post. Repeat to install the remaining adapter on the lower mark on the post. Install the adapters on the remaining posts in this manner.

Set the chop saw to make 90-degree cuts. Measure and note the distance between the outer edge of the first shelf and the center of the second post. Measure and mark two 2-by-4-inch planks to this length. The lengths of the rails between the corner sections of the fence will be the distances between the centers of adjacent posts. Measure, mark and cut rails for the remaining fence sections.

Rest the trimmed planks on the corresponding shelves of the fence adapters. In the first section of the fence the rails will extend across the shelves on the first post, the space between the posts, then end at the center of the second post. Where one adapter supports two adjacent rails, the ends of the adjacent rails meet at the center of the adapter.

Ask an assistant to stand at the front of the fence and to hold the top rail in place. From the back of the fence, screw the adapter to the rail, using a drill and driving bit. At least two screws should attach the end of each rail to the adapter. Repeat to install the lower rail on the remaining adapter. Continue installing the rails in this manner.

Tie a string to the first corner post near the bottom, at the level of the lower edges of the pickets. Extend the string to the adjacent corner post. Pull the string taut, then level the line and tie it to the corner post.

Working from left to right, position the first picket against the rails. The left edge of the picket is aligned to the ends of the upper and lower rails. The lower edge of the picket is aligned to the horizontal string. Screw the picket to the upper rail with one screw. Use a carpenter's level to plumb the first picket, then screw the picket to the lower rail. Once you've plumbed and affixed the picket to the rails, use a second screw to attach the picket to each rail.

Place the spacing block against the upper rail and the right edge of the first installed picket. Position the left edge of the second picket against the right edge of the spacing block. Align the bottom of the picket to the level string. Screw the picket to the upper rail with one screw. Move the spacing block to the lower rail, against the edge of the installed picket. Position the second picket against the spacing block, then screw the picket to the rail. Continue installing pickets in this manner until the project is done.