Nail a 1-foot-square board to a 3-foot board, 6 inches from the end.
Nail a 1-foot-square board to a 3-foot board, 6 inches from the other end.
Nail a 3-foot board to the other side of each of the 1-foot-square board. Stand up the structure so it looks like a ladder with most of the rungs missing.
Nail the last 3-foot board to the top of the structure, and flip the whole structure.
Screw a jack into the lower 1-foot-square platform using the holes in the base of the jack.
Nail a 4-inch wooden disc to the center of a 1-foot-square board. Place this board on top of the jack.
Nail two 4-inch discs to either end of the wooden dowel. This will be the piston.
Drill holes in rows and columns in a 4-inch wide PVC pipe, 1 inch apart.
Place the PVC pipe onto the 4-inch disc that's nailed to the 1-foot-square board. It should nest firmly.