Hang drums or "hanghang" as they are known in plural form are very unique and very exclusive pitched percussion musical instruments. They are made from gas-nitrided steel, look like flying saucers, and sound a bit like Carribean steel drums. If you want one you are required to travel to Switzerland where they were invented and pay upwards of $5000 for the privelege of becoming an owner. The inventors of the instrument are the only ones who make them and their service is based on personal customization and high-end exclusivity. It seems funny for a hand percussion instrument that looks like a UFO and is played on the lap to be so expensive to obtain, which is why we can make one for about $30 out of an old propane tank.
Remove the valve on top of the propane tank. This will be very difficult to remove as it is liquid-welded on. Use the wrench or a strong metal pipe to create some leverage to finally force it to come off. The hole that is left will be where the air escapes from when the instrument is played.
Remove the welded metal ring on the bottom of the tank by chiselling or manually stressing the joints. This should be less difficult than removing the valve. Try to avoid damaging the tank here as the bottom is where the notes of your drum will be played.
Draw eight "tongues" on the bottom of the tank that extend from the outer edge to the middle. These will be the notes that you strike to make sound, like keys of a piano. To prepare for the actual cutting of the notes, drill connecting holes around the curved part of the tongues you have drawn, but not down the straight lines.
Wash and clean the entire tank and get rid of any bits of metal or dust or anything else that could affect the sound when the drum is being tuned.
Tune individual notes by using the tuner and slowly hack-sawing, using just the blade, down the lines of the "tongues" you have drawn towards the outer edge of the bottom of the tank. Tape down the notes that are not being tuned to minimise reverberations as you are tuning. This is an extremely long process.
Wrap the bungee cord or other thick elastic around the middle of the drum to create less ring when playing. Paint and decorate your new hang drum if you wish.
Be patient while tuning and be very careful not to over-tune. Correcting this is difficult but not impossible. Shave down the curved part of the tongue to make the whole tongue lighter.
Be careful with old propane tanks. Try to use one that has never been filled with gas.
Adults must always supervise the use of power tools and sharp objects.