- 1). Measure the gap between the bottom of the string and crown (top) of the 17th fret with a ruler. Depending on the neck radius, the measurement on the bass side (three lower strings) should be approximately 4/64 inch (1.6 mm) to 5/64 inch (2 mm). The treble side (three top strings) should be around 4/64 inch (1.6 mm) to 3/64 inch (1.2 mm).
- 2). Insert the hex wrench into the hex screw on one side of the lowest string (E or 6th) saddle and adjust up (turn clockwise) or down (turn counter-clockwise) until the string reaches the target measurement on the 17th fret. Adjust the second hex screw on the saddle to level and stabilize the saddle.
- 3). Continue adjusting the saddles of the remaining strings until all target 17th fret heights are reached.
- 4). Play the guitar and evaluate the action.
- 5). Raise or lower each saddle as in steps 1 through 3 using a higher or lower target measurement to adjust the action to your liking.
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