Why does DAlegria use a 2-piece expansion truss rod?
The expansion truss rod is comprised of 2 pieces positioned in a certain way on which when the adjustment nut is rotated one of these pieces compresses the other, making it expand and forming an arch that pushes the neck to its rear position. With this arrangement the force imposed on the neck depends exclusively on the tension applied to the adjustment nut, what makes the neck less susceptible to climatic variations and needing less frequent adjustments. It is a more expensive truss rod and even more difficult to produce and install, but it is worth it due to the stability granted to the instrument’s neck. This fact also minimizes the chance of any torsions or “S” bendings on the neck, since the truss rod’s tension only acts in a way of compensating the strings tension, without compressing the wood.
