How to Adjust the Bridge for Heavy Strings

The strings pull on the bridge when tightened.

The tension of your strings determines the position of the bridge, relative to the body. If the tension is high, this can pull the bridge away from the body. This causes the bridge to tilt, which impedes the guitar's playability as the clearance between string and neck becomes too high. The heavier the string gauge, the more tension the strings apply to the bridge. If you replace your current strings with a heavier gauge set, you must adjust the bridge to compensate for the increased tension. This maintains a suitable bridge angle.

Things You'll Need

• Feeler gauge
• Phillips screwdriver

Instructions

1. Tune the guitar. Bridge adjustments involve balancing the tension applied by the strings with the tension applied by the bridge springs. To do this accurately, the guitar must be in tune to begin with.

2. Use a feeler gauge to measure the clearance between the strings and the neck at fret 12.

3. Remove the tremolo arm if there is one. Depending on the make and model of your guitar, the tremolo arm will either screw out or pop out. If you do not know which type you have, try unwinding the arm from the socket. If it does not become looser, it is not a screw-in arm. In which case, gently pull it toward you. Always remove the tremolo arm before laying your guitar face-down.

4. Lay the guitar face-down.

5. Unscrew the back panel in the center of the guitar. This exposes the bridge cavity. In here you will see an inertia block and a set of springs. The number of springs varies according to the type of guitar you have. The springs apply tension to bridge. This tension compensates for the pull applied by the strings. The springs are attached to a mounting-plate, which is screwed into the far wall of the bridge cavity. The screws are not fully anchored into the bridge cavity wall; there is typically around 1/2-inch of thread left outside of the wall. This extra thread permits you to move the mounting-plate closer to the wall of the cavity, increasing the tension of the springs and pulling the bridge down.

6. Tighten the screws attached to the spring mounting-plate. Adjust each screw by an equal amount.

7. Turn the guitar face-up.

8. Fit the feeler gauge under fret 12 and measure the clearance. The clearance is a matter of preference and playing style, but it should ideally not exceed 3 mm at fret 12. Clearance greater than 3 mm will make it difficult to push the strings down.

9. Tighten the screws again if necessary.

Tips & Warnings

• If you have a Tune-o-matic bridge such as those used on Les Paul guitars, the string tension does not influence bridge position, so no bridge adjustment is necessary.

References

• Ibanez: Help and How To
• Fender: Stratocaster Setup Guide