Crouching to operate my compressor's drain valve was no big deal until my football-ravaged knees started acting up. To keep from grimacing in the sawdust, I devised a more civilized way to clear the tank. I replaced the drain valve with a 90-degree elbow, a 200-psi-rated reinforced hose and a ball valve. Barb fittings on the elbow and ball valve and clamps on the hose keep everything air tight. I chose a ball valve instead of an air nozzle so no one would mistake my new drain hose for a regular air hose.