Rain water collection. Nature's most fundamentally important resource for human habitation -- the earth purifies it from all sorts of sources through the evaporation process, transports it all around ...
Install the bulkhead fitting by removing the nut and friction washer, then passing the fitting with the rubber gasket attached from the inside of the barrel through to the outside. Install the friction washer then thread on the nut. Finger tighten the fitting.
Note: The left-hand threads of the bulkhead fitting will provide counter-rotation when tightening the right-hand threaded valve assembly into the fitting.
Attach the nipple to the valve, applying Teflon tape to the male threads. Use slip-joint pliers to create a tight union.
Apply Teflon tape to the male threads and join the valve assembly to the bulkhead fitting. apply the pipe wrench to the bulkhead fitting washer and tighten the valve assembly. Tighten the valve assembly firmly and rotate the valve handle to the top. Then use the pipe wrench to tighten the bulkhead fitting.
It's easy to over-tighten this connection and deform and possibly weaken or damage the barrel, so wait until the barrel is filling with water to determine how much torque is needed to keep water from leaking through this joint. Adjust the tightness of this fitting to be just tight enough to keep water in when the barrel is full. Hold the valve in the desired position and turn the large nut with the pipe wrench. Remember, left-hand threads tighten the opposite direction! The nut on my fitting actually depicts the direction to rotate (counterclockwise) to tighten.