A guitar’s neck bow is a significant indication of the overall quality of the instrument, and it is important for a player to know how to check their neck for this defect. Fortunately, the process isn’t difficult, but it can provide significant insight as to the health of your acoustic or electric guitar and whether or not your have a twisted or warped guitar neck.
How To Check Guitar Neck Bow
You will need:
- A ruler or straightedge
The bridge saddle height should be such that the low E string is just slightly higher than the twelfth fret when fretted at the first and eighteenth fret (see measurements). When viewed from the end of the fingerboard, a straight line should run through the seventh, twelfth and seventeenth frets.
The neck bow or neck relief is the deviation of this straight line and the bend usually can be corrected with a truss rod adjustment. Ideally, the centerline should run through the seventh and twelfth frets. The most common deviations are concave (bow) or convex (swayback), but it can also be lateral (side-to-side). This will help eliminate fret buzz and make the guitar a lot easier to play.
I’d recommend following this video for more information on how to check for this:
With this method of checking the neck bow, it is important to first identify if the centerline is accurate. If not, you will need to measure and mark the other two positions to ensure that the centerline is correct.