The term “drone flute”--as well as the terms “double drone flute,” “double barrel flute” and “double flute”--denotes either a flute with two chambers built into one flute body, or two flutes connected by a single mouthpiece and a connecting piece of wood. Only one of the chambers (or flutes) has finger holes. The second chamber is usually tuned to the bottom note of the flute, a single note drone.
The best way to learn how to build these unusual instruments is to join a flute-making Internet group; order a DVD or book on Native-style flutes; take a class or buy a kit that makes assembly very easy and straightforward.
Read a manual. The "Ki-e-ta Flute Making Manual," for example, which boasts photos and detailed instructions, also recommends which tools work best. Oregon Flute Store’s "Flute Shop Workbook" has details and illustrations for making six-hole flutes in the keys of G minor, B minor and F-sharp minor, and it provides information on crafting various Native American-style flutes.
Buy a kit if you’re daunted by the idea of building a drone flute from scratch. Stellar Flutes’ drone flute kit, for example, is constructed from two matched flute blanks joined by a walnut slat. It comes drilled with tuning to the pentatonic scale. The drone hole is optional.
Take a class. Some flute groups offer kits along with a flute-making workshop. At festivals such as Flute Quest, an annual gathering of flute enthusiasts in Washington state, participants make their own drone flute from a pre-tuned drone flute kit, and they learn advanced techniques such as voicing, balancing, and tuning a drone-style flute. Search Craigslist, flute forums, woodworking instrument forums, and local flute and world music instrument stores for more information.
Join an Internet group. Yahoo and Google both have versions of the Native Flute Woodworking group, in which forum members share information about making Native American style flutes, from tools to techniques and designs to other links and resources.