Hollow building a bamboo fly rod means exactly what you’d expect: Material from the inside of a bamboo rod is removed leaving open spaces within. Tests have proven that the strength of bamboo comes from the dense power fibers located in the outer circumference of the culm. The purpose of removing the inner pith material is to make the rod lighter in weight while making it rebound and recover quicker with less bounce and excess vibration. Hollowing involves removing the softer, inner pith of a beveled and shaped bamboo strip.
