How to Make a Post Driver

Thread the cap onto the pipe.

Tighten the cap. Fit one pipe wrench just below the threaded end of the pipe on the left-hand side, and fit the second pipe wrench on the right-hand side of the cap. To get the best leverage on the wrenches, there should be no more than a 15-degree arc between the two handles. Pull the handles of the wrenches together. Repeat until the cap is tight.

Turn the capped pipe upside down, and apply a mild corrosive to the seam between the cap and the pipe. For this application, a commercial thread adhesive or a carbonated cola drink poured over the exposed threads will work.