Place one 2-by-12-by-36-inch board flat on a work surface. Measure the board from one end and mark it at 6, 12, 18, 24 and 30 inches with a pencil.
Drill a 2-inch hole through the board you marked in Step 1 at each pencil marking. Drill the holes through the center of the 12-inch width of the board. Use a drill press equipped with a 2-inch hole saw to drill each hole.
Adjust the table saw fence to saw the drilled board in half lengthwise and lock it in place. Lieay the drilled board flat on the table of the saw and guide it through the saw in a steady motion to cut it in half lengthwise. The drilled holes will now be cut in half and form the cupped edges of the top support boards in the rod holder assembly.
Sand the cut edges of the two halves of the board with a fine-grit sanding pad until they are completely smooth.
Drill a 1/8-inch hole through the center of each PVC pipe cap using a drill press equipped with a 1/8-inch drill bit.
Lay the remaining 1-by-12-by-36-inch board flat on a work surface. Measure and mark the board at 6, 12, 18, 24 and 30 inches using a tape measure and pencil. Center one PVC pipe cap over each pencil marking with the open end of the cap facing up. Drive a pan head screw through the 1/8-inch hole in each cap into the board using a screw gun. This is the bottom board of the rod holder assembly.
Slide one 6-inch PVC pipe into each cap on the bottom board of the rod holder assembly. The handles of the rods will side into the pipes at the base of the rod holder.
Stand one 1-by-12-by-48-inch board upright on each end of the bottom board of the rod holder assembly. The 1-by-12-inch ends should be flat against the work surface. These are the sides of the rod holder assembly. Drive four evenly spaced 3-inch deck screws through the outside sides of the two upright boards into the ends of the bottom board using a screw gun.
Position one half of the board that was cut in half lengthwise between the two upright boards so that the halves of the holes are facing you. Place this board at the top of the upright boards. Position the second half of this board in the same manner 12 inches down from the first half. These are the top support boards.
Drive two evenly spaced 3-inch deck screws through the upright boards into the ends of the top support boards with a screw gun to complete the assembly. The top parts of the rods will rest against these support boards.