Woodworker's Journal 1984-8-5, страница 36

Bongo Box

by Johanna Walton

The bongo box is an ancient instrument that most likely evolved from a hollow log. The Aztecs, Mayans, and Incas in South and Central America, are but a few of the many tribal civilizations who used the bongo box in ritual and dance.

The bongo box is played by striking the different sized wooden tongues or keys. The sound is generated by the vibration of these tongues against air inside the box's hollow core. To experience the "feel" of this sound, place your hand over the sound hole while the keys are played.

Despite its apparently simple design, we have discovered that the construction of a box that will demonstrate good resonant quality requires adhering to very strict parameters. Type of material, thickness of stock — for top, bottom, and sides — size and shape of the box, size and location of the sound hole, width, length, and shape of the "tongues" and their distance from box sides — all these elements impact on the type of sounds and the box's resonant quality. Although we built a to

tal of four boxes in various shapes and using different materials, none worked nearly as well as this first box. Because there are so many separate factors that effect the tonal quality, we strongly recommend carefully following our original design for best results.

The bongo box is built from V* in. redwood and cedar, with a '/» in. mahogany-ply bottom. All joints are simply glued, butted tight and clamped. Begin by cutting the redwood sides (A) and ends (B) to size. Glue up and clamp these four sides. Next, cut the cedar top (C) and mahogany-ply bottom (D). Both these pieces should be cut slightly oversize, so they may later be sanded flush.

The tongue pattern is cut out after the box has been assembled. Transfer the illustrated grid pattern to the bongo box top, and first drill out the V» in. holes. These holes serve as starting points for the saber saw as you cut the individual tongues. Use a fine tooth metal cutting blade for the smoothest possible cut.

After the cutouts are complete, take

a hacksaw blade or thin file and carefully clean out the kerfs. This is especially important since any wood chips or fuzz that is caught in the kerfs will cause the keys to sound flat.

The I'A in. sound hole in the box side may either be cut with a Forstner bit on the drill press, or by first drilling a ³/» in. starter hole, and then cutting the circle out with the saber saw. The two drum sticks are simply Vi in. dowel rod epoxied into plastic "jack" balls.

The bongo box looks best with a natural finish, achieved by rubbing in lemon or tung oil.