I recently had the privelage to do a workshop with my guru, a master of the bansuri, on crafting the instrument. I learned about the various materials, techniques, and nuances of creating a bansuri, and that each flute is its own unique work of art.
Bansuris are typically made out of special types of bamboo that vary depending on how its creator wants the flute to sound. The bamboo is cut to specific lengths based on its width, with shorter and narrower flutes producing a higher scale of sound than longer and wider flutes. After this, the bansuri is "seasoned", by treating it with natural oils on the outside to strengthen and preserve the flute. The inside of the flute is then sanded to ensure the clarity of the notes when playing. One end of the bansuri is sealed with a cork to ensure that the air travels past the finger holes to escape, rather than escaping through the mouthpiece. The placement of the holes on the flute are carefully marked, after which the holes are burned in with a very hot metal rod.
Although bansuris are versatile, sturdy instruments, they still require occasional maintenence and caretaking. Firstly, bansuris should be kept in a protective case, and stored in a dry place at room temperature -- not too hot and not too cold. Since bamboo is a natural material, heat and cold can easily cause it to expand and contract, which often results in cracking. In addition to this, once a year, a thin layer of castor oil (from castor seeds) should be applied on the inside and outside of the flute. This strengthens the bamboo and prevents microcracking, which causes increasingly larger innacuracies while playing the flute.
Through the guidance of my guru, I discovered the spiritual connection between the craftsman and the instrument. The bansuri isn't just an instrument, it’s also a harmony of craftsmanship and dedication.