A bowed neck can cause all sorts of problems. Poor intonation and fret buzz are among the top two. In this tutorial you’ll learn how to check the straightness of a guitar neck and make adjustments based on your assessment. A properly adjusted neck lays the foundation for a good setup.
Tools
- 12 or 15 in. (30cm or 40cm) Metal Straight Edge
- Alan Wrench, Hex Key or Socket Wrench
- Light Piece of Paper, Paper Towel or light cloth to use as a backdrop
- Phillips Head Screwdriver (if your guitar has a truss rod cover)
Visual Assessment
First, hold your guitar up and sight down the treble and bass sides of your instrument’s neck checking for any signs of a bow.
Physical Assessment (and Diagnoses)
1. Place a straight edge flat on the frets in the middle of your guitar’s neck between the E and A strings. Now check for any rocking by alternating slight pressure downward on the opposite ends of the ruler.
Diagnosis: If the ruler rocks up and down at all, your guitar probably has a back bow.
2. Now check for any signs of a gap underneath the frets. (You should use a white piece of paper or a light colored cloth as the back drop when you do this.)
Diagnosis: If you notice a gap between some of the frets and the bottom of the ruler then you probably have a forward bow.
3. Repeat Steps 3 and 4, first between the D and G strings, and then between the B and E strings.
Once you complete your assessment you should have a good picture of the overall health of your guitar’s neck. If you were able to assess your neck’s condition correctly, then you will know whether you have a back bow or a forward bow; or if you’re lucky and your neck is perfectly straight.
Adjustment
During your assessment you should have been able to determined whether your neck has a back bow or a forward bow. Click one of the links below to determine how to correct a back bow or forward bow. (If your neck has no bow in it at all then you should move on to the next step.)