- If you have neck tilt adjustment, loosen up the screws that hold the neck on.
- Use the allen wrench to back off the neck tilt adjustment screw that is accessed from the hole in the plate the neck screws go through.
- After you have loosened the tilt screw, re-tighten the neck screws. The tilt screw should still be completely slack after the others are tight. Don't worry, we'll come back to it later.
- Next, string up the bass with the set of strings that you will be using. Try to only have about three turns of the string on each tuning peg.
- Tune up your bass to the tuning you will be using. If the pickups look like they are too close to the strings, use a screwdriver to lower them.
- Place a capo on the first fret. (The strings are basically used as a straightedge)
- To get as accurate a measurement as possible, hold the bass in the same position as you play it.
- Hold down the string at the last fret (for me, the 24th) and measure the distance between the string and the fret at the half-way point on the finger board (for me, the 8th).
This will tell you how much relief the neck has.
- I set mine at about .5 mm between the string and the fret. Choose the proper thickness on the feeler gauge, and see if you can fit it in between the string and the fret without lifting the string.
Measuring String Relief
Truss Rod Adjustment
If the distance is less than desired, then you have to loosen the truss rod. If the distance is more than desired (larger gap), then you have to tighten the truss rod. Only tighten or loosen the truss rod nut about an 1/4 of a turn at a time, no more. If you have an old
P-bass, you'll have to actually remove the neck from the body to do this properly.