To put it simply, electric guitar action is the distance between the frets and the strings. If the action is too high (too much clearance), the guitar will be hard to play. Low guitar action will cause fret buzz. The gauge of guitar strings that are used, the type of music played and the way the instrument is played determines how high or low the electric guitar action needs to be. It should be noted that
if an extremely high guitar action adjustment is required to silence the fret buzz, it’s time to check the truss rod adjustment or the fret height alignment. High frets are very troublesome, but repairable. If your guitar has a fret alignment issue, talk to a luthier or a qualified technician about dressing the frets before proceeding with the electric guitar setup.
To fully understand how to properly adjust the electric guitar action we must first examine the guitar fretboard radius. It should be noted that the neck profile and the fretboard radius are completely different
factors, although the neck profile is commonly referred to as the neck radius. Simply put, the radius is the amount of the curve designed into the fretboard calibrated in inches. The larger the radius number, the flatter the fretboard. As an example, a guitar fretboard with a radius of 7.25 inches is more convexly curved than a fretboard with a radius of 12 inches.
The electric guitar fretboard radius is a matter of personal preference. The desired
fretboard radius depends on the type of music being played. A more rounded fretboard
radius is better suited for strumming chords and playing riffs. A prime example is
the 1950’s era Fender Telecaster with its 7.25 inch fretboard radius. The Telecaster
achieved prominence in the post-
the player’s fingers to move faster across the strings and is preferred by many Rock and Blues players. An example of this is Gibson’s Les Paul Series and electric guitars manufactured by Jackson, ESP and Dean which are produced with a fretboard radius of 12 to 16 inches.
There are also electric guitars produced with a conical/compound radius fretboard which offer the ultimate in playing versatility. These guitars
come up with a matching radius.
To adjust the electric guitar action on a “Tune O Matic” style or Floyd Rose Bridge, use the adjustment screws on each side of the guitar bridge to raise or lower the bass and treble E strings to the desired measurements.The bridge design will automatically follow the fretboard radius and set the action on the A,D,G and B strings. If your electric guitar has individual adjustable saddle blocks, such as the Fender Bridges, use the bridge saddle block adjustment screws to set the bass and treble E strings
are designed with a rounder fretboard radius on the low end of the neck (the end closest to the nut) and a gradual transition to a flatter fretboard radius on the high end of the neck.
The most commonly produced electric guitar fretboard radius measurements are 7.25, 9.5 and 12 inches. To find the fretboard radius of your electric guitar you can check with the manufacturer or make a radius gauge which will also be of great assistance with action adjustment. To make a radius gauge you will need a compass, some light cardboard such as a breakfast cereal box and a pair of sharp scissors. If you don’t have access to a
compass, a sharp pencil and a piece of string can be used. Simply find a focal point and set the compass on the radius measurement (7.25 inches or the appropriate radius number) and draw a circle. If a pencil and string is being used, mark a center point for the circle and mark a distance from the center point equal to the fretboard radius number. Tie the string to the pencil and tack the untied end to a center point on the cardboard so the pencil lead is lined up on the radius measurement mark when the string is pulled tight. Then draw a circle.
Cut a segment of the arc drawn that is approximately 3 inches long and that will give you a radius gauge. If you don’t know your fretboard radius measurement, follow the above procedure and make a separate gauge for a 7.25, 9.5 and 12 inch radius. Then set the different cardboard radius gauges on the fretboard at the fret you are using to adjust the guitar action and see which one matches the radius of the fretboard. Check with your guitar’s manufacturer for the recommended fret to check the action on. If your fretboard radius doesn’t line up with any of these sizes, go back to the cardboard and try different measurements until you
to the designated clearances.Then lay the fretboard radius gauge across the strings at the fret you are using to set the action. Adjust the A,D,G, and B strings where they follow the arc of the gauge and allow it to sit flush on the bass and treble E strings.
To check the electric guitar action adjustment, bring the instrument up to tune and lay it flat using a neck stand on a padded table or guitar work stand. The fret used to measure the guitar action and the action measurements vary depending on the electric guitar manufacturer. If the manufacturer’s recommendations are not available, the common con census
is to use the twelfth fret with 6/64” on the bass side (low E string) and 4/64” on the treble side (high E string). Using a small scale, measure the distance between the top of the designated fret and the bottom of the string being measured.
Set the clearance on the bass side (low E string) and on the treble side (high E string). Depending on what type of bridge your instrument has, raise or lower the guitar bridge or the string saddle blocks to get the desired clearances. These action measurements are only a reference point. Guitar action is a matter of personal preference, so you can start with these clearances and set up your electric guitar exactly how you want it.
Now that you have the guitar action adjustment set where you want it, Electric Guitar Intonation Adjustment is the next step in the electric guitar setup process.