Here is an overview of the design elements that set these necks apart from all others:
The Double Expanding Truss Rod
for Warmoth Guitar Necks
The double rod is installed directly under the fretboard in a straight trench approximately 3/8" deep. A long adjusting nut is used to
focus the truss action away from the unmovable heel joint.

When flexed in the neck, resulting pressures are shown above. The blue arrows show the two rod ends exerting high downward forces while
the middle pushes up uniformly. The resulting neck movement shown with the yellow arrow, determines string action height and corresponding relief.
The force exerted by the tail end of the double rod is considerable. There must be a minimum 1/8" of wood below the rod end to prevent
wood failure in this area. This becomes a concern only when thinning a neck beyond factory engineered dimensions.
Benefits of the double expanding truss rod
- Extremely stable, no seasonal adjustments are necessary
- Increased mass = longer sustain, cleaner and clearer notes
- No end to end wood compression to eventually distort the neck
- Top adjusting on 13° Angled necks
Drawbacks
- Double the weight of vintage rod
- More torque required for adjustment
- More expensive to manufacture