Paul Discoe on the Han
Paul Discoe page
The traditional han in the Soto lineage, and therefore the one that can be bought from the Buddhist supply store, is plus or minus 20 inches by plus or minus 14 inches. The bottom is straight, the two sides taper in slightly towards the top, and the top has a slight peak in it. It's the traditional shape of sign boards, and I don't know what its origin is, but you see it everywhere. Just like the stop sign in the United States is that octagonal shape and everyone knows that means stop sign, that pentagonal shape means message, in Japan if not in China as well.
The ones that I saw in usage in Japan are relatively thin, as maybe an inch and a quarter or an inch and a half. The concept is that it's thin enough to make a resonant sound that travels a long ways, and you destroy it in a relatively short amount of time, like even one ango. Traditionally there's a party when you break the han, and so the concept of it lasting for a long time is not so important.
In the West, there's been a tendency to make them very thick and heavy, and cut out a sounding relief in the back, which is inconsistent with my understanding of the han.
My style of putting in the handles is drilling two holes vertically in the top about six inches apart, and two holes vertically in the bottom, and then on the backside, drilling two larger holes that go halfway into the han and connect with the smaller holes coming in from the bottom and down from the top. You fish a piece of rope through these holes and out the back, and then tie a knot and pull it back tight and cut the excess off, making a handle for the top and the bottom.
Generally when being used, the han is hanging and being pulled in tension from the strap below. The hammer from the han is an important part of the acoustics. The hammerhead should be approximately two to two and a half inches in diameter, whether round or octagonal. It should be six plus inches long, and come to a blunt point at both ends, leaving a flat space about 3/4" square as the striking surface. The handle is generally slid through from the top in a tapered through mortise. The handle is then tapered so that when you slide it in from the top, the part you hold is smaller than the opening and the top end is slightly fatter, so that it catches in the mortise as it slides down.
The way the hammer is used is very different from western style hammers. It is more like it is a weight on the end of a string that you swing and virtually throw at the striking surface. For example, a large sledgehammer for breaking up rocks in Japan has a hole in it the size of your finger, so that the handle is just a way to get the weight of the head to swing in a circle and come down on the surface. Westerners have a tendency, being chest oriented rather than Hara oriented, to hold the handle very firmly and power the head into the striking surface as if they were driving a nail. Once again, an interesting division in the east/west way of approaching a problem.
The message written on the han that is being broadcast by the sound of the han is translated in several different ways. The one I have is "The Great Matter of Birth and Death/Impermanent Swiftly Passing/Awake Awake Everyone/Careful Do Not Waste Time", or as I recall Suzuki Roshi's interpretation - "Don't goof off".
The wood can be any hardwood that is not easily split. The traditional wood is keyaki, or elm. But the most important part is, don't be late.
b/w images from SFZC Wind Bells - the color photo is Tassajara but don't know where came from. - dc
See The Sound Instruments in a Zen Monastery from the Terebess site - lots of good graphics on the han there.
Han is the Japanized Chinese for wood. The kanji is generally pronounced that way when combined with other characters to make words. The same character is usually pronounced kayu which is the normal Japanese for wood.