Indian flutes

[Charles W. (Charlie) Brown]

The Indian flute is unique in that it has two chambers, the sound chamber and a Slow Air Chamber.

[Charles W. (Charlie) Brown]

[Charles W. (Charlie) Brown]

Start by setting the router bit to 1/2 the diameter of the bore.

 

Most of what I've read calls for 7/8 inch bore. I haven't been able to locate a 7/8 router bit, so I use 1/2, 3/4 and 1 inch. 3/4 shown.

 

Note:

There's a law of physics that limits the length of the bore to 18 times its diameter. Longer than that and you get no sound.
 
Charles W. (Charlie) Brown said:

[Charles W. (Charlie) Brown]

Clamp a wood fence to the table placing it the thickness of the flute wall away from the cutter and mark the front and back edges.

[Charles W. (Charlie) Brown]

This is what we're trying to accomplish:

[Charles W. (Charlie) Brown]

Lay out the flute on two halves:

 

3/4 diameter, 13 inches long, space between the chambers:

1/4 - 1/2 (1/2 shown), Slow Air Chamber 2 - 4 inches long (2 in. shown)

[Charles W. (Charlie) Brown]

Rout the sound channel.

[Charles W. (Charlie) Brown]

Carefully lift up the blank and move it over to begin the SAC.

[Charles W. (Charlie) Brown]

Finish the Slow Air Chamber.

 

Do the other half the same.

[Charles W. (Charlie) Brown]

Change cutters and rout the entry channel, 1/8 - 3/8 diameter, 1/4 shown.

[Charles W. (Charlie) Brown]

You now have two identical halves.

[Charles W. (Charlie) Brown]

Pick the side with the best figure and rough out the transition holes. You only need to mark the spot where they exit. These can be 1/2 the diameter of the two chambers. I'm using a 1/2 inch chisel here. Because moisture in the breath condenses out in the SAC, waterproof both sides and the mouthpiece hole with lacquer, shellac, urethane, etc. sand the sides smooth so glue will stick.

[Charles W. (Charlie) Brown]

Smear glue on both halves. Use a dowel to align them.