The mere idea of adjusting the truss rod can strike fear into the heart of many bassists and guitar players. It’s as though one false move will ruin the instrument’s neck forever. While it is true that you can break the truss rod if you are not careful, it is possible to make this adjustment yourself.

The truss rod is an adjustable steel rod running the length of the neck. Its purpose is to adjust the amount of relief, or forward curvature, of the neck. The heavier the string gauge, the more the strings will pull the neck into relief. The truss rod can be tightened to counteract the pull of the strings, or loosened if more relief is needed. Virtually all modern electric basses have a truss rod.

The first thing you should be aware of is when the truss rod might actually need an adjustment. You might need to loosen the truss rod if you are getting buzz in the first five frets or if you have changed to a lighter string gauge. Similarly, if the instrument is uncomfortable to play due to high action in the lower frets, or if you have gone to a heavier string gauge, you might need to tighten the truss. Adjusting the action at the bridge will be more effective than a truss rod adjustment on the higher frets, and these two adjustments (bridge and truss rod) can be used together to get the action where you like it.

Once you have determined that you need to adjust your truss rod, the usual method is to give it no more than a quarter turn at a time. It can take up to a full day for the adjustment to be noticed, so if your instrument doesn’t feel different right away, wait. If it still is not in proper relief after one day, another quarter turn is OK, but if you can’t get your bass adjusted within a half turn, you might want to have it looked at. Maybe the buzz is from a high fret. Maybe the high action is because the nut is not cut right. Sometimes a truss rod needs more than a half turn, but usually that is because the instrument was not in playing condition in the first place. If your instrument is in playing condition it should not need more than a half turn.

Keep in mind that over tightening the truss rod can cause it to break. You can also simply run out of threads and have no more room to straighten the neck. What should you do if you break the truss rod? Cry! Some Warwick and Spector basses have removeable truss rods, but usually the neck needs to be taken apart to replace the rod. This is a $300-$400 procedure involving removing the fretboard, replacing the truss rod, regluing the board and then refinishing the neck. The moral of the story is – be careful!!!

If the truss rod is stuck and won’t turn, it could be that you have run out of threads. It could also be a burr or some foreign material in there. You can remove the truss rod nut and clean it up. If you think you have run out of threads there are washer kits that can give you a bit more room to straighten the neck. You basically remove the nut, add some washers, and then reinstall the nut.

There is nothing wrong with taking your instrument to your bass tech for adjustment. Your instrument is a valuable tool and it makes sense to keep it in good working order by having a professional look at it. But adjusting the truss rod is not as scary as some people make it out to be and as long as you are careful, you may be able to make this adjustment yourself. Good luck!