Luthiery Laboratories

This is my favorite truss rod design. It is not my most advanced, but it is the simplest to build. Although it is a single-acting rod, a little forethought in routing the channel makes it reversible, effectively double-acting. That requires some disassembly of the guitar, but you only need to change the direction of the rod once or twice in the life of an instrument, until it settles in to a mature shape.

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