Step 1
Cut and bend the water trough into a 6-foot-x-6-foot square. This will serve as the water collection and supply reservoir. Completely seal all joints in the trough so it is water tight.
Step 2
Place the 12-volt water pump in the bottom of the trough and fill with water to cover the pump.
Step 3
Build a 6-foot support structure above the trough out of steel pipe. This structure will hold up and support the water-laden cooling pads.
Step 4
Attach tubing from the output of the pump to the center of each of the four sides of the support structure. The pump generates a flow of water across the surface of the cooling pads.
Step 5
Suspend a 6-foot-x-4-foot cooling pad from each side of the support structure. Direct the water supply line output onto the top edge of the cooling pads at the center of the sides. Connect the pump to the 12-volt battery. When the pump starts, the water will flow across the pad and begin to cool the air passing through the pads.
Step 6
Add water to the trough as the pump supplies water to the pads until they are saturated. Continue to add water until the water level in the trough stabilizes. When the pads saturate with water and drip off the bottom edge back into the trough, you should feel a flow of cool air escaping under the bottom of the pads.