Adjustable Truss Rod

by Jim Williams

Originally published in Guild of American Luthiers Data Sheet #277, 1984 and Lutherie Woods and Steel String Guitars, 1998



For many and varied reasons, many luthiers are wary of adjustable truss rods when building instruments. The most obvious reason is the difficulty of making and fitting a conventional truss rod as used by Gibson, Guild, and others. The efficacy of this system is often doubtful as well, plus there’s the legacy of broken pegheads that often results from the excavation of wood to accommodate the adjusting wrench. The drawings illustrate the difference in operation between the conventional system and the system I am describing which is similar to that used by Gurian and Rickenbacker. This method is also great for mandolins.

You will need a 3' length of 3/16" steel rod, a small block of brass 1/2"×1/2"×3/8", a 3/16" U.N.S. thread Allen nut (what you in the U.S. call 10×32) and some 3/4" wide fiberglass packaging tape.