Truss rod apparatus

An apparatus for adjusting neck curvature in a stringed musical instrument, comprising:

• (a) a first elongate member having a first end and a second end;
• (b) a second elongate member positioned adjacent to and parallel to said first elongate member, the second elongate member having a first end and a second end, the first end of the second elongate member being fixedly connected to the first end of the first elongate member;
• (c) anchoring means to which the second end of the first elongate member is fixedly attached, the anchoring means being positioned at one end of the musical instrument neck;
• and
• (d) rod length adjusting means having a hollow threaded bolt having internal threads and external threads, the internal bolt threads threadedly engageable with external threads on the second end of the second elongate member, the external bolt threads threadedly engagable with a threaded passageway through the anchoring means, said length adjusting means being connected to the second end of the second elongate member for axial movement and length adjustment of said second elongate member relative to the first elongate member and the anchoring means.

A truss rod apparatus, in use situated within the neck of a stringed musical instrument, for variably adjusting neck warping of the instrument, comprising:

• (a) a first rod;
• (b) a second rod parallel to the first rod and joined at one end to one end of the first rod, the free end of the second rod having threads;
• (c) an anchoring block to which the first rod is joined, the block having a threaded passageway defined therethrough, the second rod being axially movable within the passageway;
• and
• (d) a hollow threaded bolt, the bolt having external threads and internal threads, the external threads having a greater pitch than the internal threads, the external threads threadedly engagable with the threads in the block passageway, the internal bolt threads threadedly engagable with the threads on the free end of the second rod, whereby the second rod may be axially extended or retracted relative to the block without radial movement of the rod.