Questions: Adjustable Truss Rods

by John Calkin

Originally published in American Lutherie #74, 2003 and Big Red Book of American Lutherie Volume Seven, 2015



Steven D’Antonio of Bellingham, Massachusetts asks:

I have been using the Hot Rod 2-way Adjustable Truss Rods made by Stewart MacDonald for several years with good results. I have been placing them dead center in the neck without any problems that I am aware of. But recently I read something by John Calkin in AL stating that since the treble strings are under more tension than the bass, some luthiers offset their truss rods toward the treble to compensate for the imbalance in tensions. I asked Stew-Mac and also LMII for their advice, and they both suggested dead center placement for the truss rod. If you suggest offsetting towards the treble, how much is enough?


John Calkin of Greenville, Virginia answers:

It’s pretty common to find that when the neck of a guitar with some age on it is adjusted, the treble side still has a slight bow after the bass side of the fingerboard is flat. Pulling out the bow on the treble side will often fret out some of the bass notes nearest the nut. Usually this is a minor affair, but occasionally the only fix is some fret filing or even a refret after the fretboard has been trued. I tend to think of this as an electric guitar problem, but that may only be because electric guitarists are more obsessive about having the lowest possible action.