The bansuri is a six- or seven-holed flute of North India, made of bamboo, cane, or reed. Reed flutes are associated with Krishna.
The transverse bansuri is a length of reed with holes in it, allowing for good tone control by varying one's embouchure. The fipple bansuri has stoppers, which limits the flexibility of the musician.
If you are trying to make a reed flute, there are various techniques in bansuri-making that could help. The wider end of the bamboo should be at the open end of the instrument, away from the mouth hole. The body of a reed flute tends to crack, so it should be wrapped evenly with twine. To make sure the twine is giving even pressure, tie a heavy weight to one end of it, and turn the bamboo-- rather than winding the string with your hands.