A hank drum is a drum made from an empty propane tank. The design was invented by Dennis Havlena, a musician who has invented many new and hybrid musical instruments since the '60s. It was designed after the tambiro and the Swiss hang drum. Properly tuning the hank drum is the key to getting the right sound out of it. The hank drum sounds similar to a xylophone with duller tones.
Buy a brand new 9.07kg. propane tank. This tank should be brand new and never filled.
Release the air pressure inside of the tank by turning a screwdriver on the side of the valve where the tank is filled. Use a large adjustable wrench to try and loosen it by gripping the valve with the wrench and turning with great strength.
Break the brackets off of the bottom of the tank using the wrench. Grip the bracket with the wrench and wiggle vigorously until it comes off. File down the leftover metal from the break until the bottom of the tank is smooth all over.
Print the hank drum pattern (see Resources) and tape it to the bottom of the tank. The bottom of the tank is the hank drum's drumhead.
Use a marker to trace the pattern onto the surface.
Cut the tongues with a jigsaw that has a blade designed to cut metal. Trace the lines of the pattern with the jigsaw blade.
Tune the tongues using a digital tuner. Tap on each tongue until the sound reaches the desired tuning. This step is most important for the sound of the hank drum. Use electrical tape to mute the other tongues while tuning one at a time. Place the tape at the top of the tongue and the tank across the cut from it.
Wrap the tank with rubber tie-downs. Place one around the top of the tank and the other around the bottom. These will help to dampen the drum and reduce the ringing sound.
Make sure that you stop short on each tongue. This leaves you room to tune each tongue later. Prying the tongues out a little can improve the sound. Leave the larger tongues open while tuning the highest two tongues.
Never use a propane tank unless it is brand new and has never been filled with propane.