Can you loosen a truss rod too much and will it damage your guitar? Guitars are quite sensitive instruments and it’s easy to understand why guitarists of all levels are worried that truss rod adjustments can negatively affect the neck of their instruments.
While adjusting your truss rod is not exactly rocket science, doing it the wrong way can only create bigger problems to the extent that the playability can be compromised. At this point, the service of an expert is the only recourse and if you don’t have a backup guitar, your jam sessions and live performances will certainly suffer from this predicament.
However, not all guitar players have the luxury of having a luthier or a guitar technician in their area, especially if they are living far away from the city center or touring in a secluded town. Most often, the action or string height of a guitar can shift without any intervention as a result of sudden changes in weather and temperature. It can be difficult for some guitarists to seek professional help and sometimes the only option is to take matters into their own hands.
Knowing the role of truss rods and how to adjust them is one of the things that every guitar player should prioritize. It is important to educate yourself on these vital aspects even before purchasing your very first guitar, to grant you a deeper understanding of the instrument.
Having ample knowledge about truss rods, as well as other crucial parts of the guitar can also give you a chance to ask advice from experts at the music shop. This will help you address future guitar issues on your own without making any errors that could be detrimental to your instrument.
The function of truss rods in guitars
A truss rod is a steel bar that goes through the neck and underneath the fingerboard. It is responsible for stabilizing the lengthwise curvature, or relief, of a guitar’s neck.
A vast majority of guitars today are fitted with truss rods that can be adjusted to tighten or loosen the tension, in case the neck bends due to humidity and changes in the atmosphere. Although the truss rod is not designed to adjust intonation or action, tweaking it can contribute to the improved playability of your guitar since it also influences string height.
Old guitars and cheap knock-offs that don’t have truss rods, can be very difficult to repair in case bending or warping occurs. Except for classical acoustic guitars which don’t require truss rods due to the much weaker tension caused by nylon strings, it is of utmost importance that you choose guitars that are equipped with one.
How to adjust a guitar’s truss rod?
Legendary luthier and repairman Dan Erlewine himself advises guitarists to not be afraid of adjusting the truss rod by themselves. The author of several best-selling books on guitar building and repair even encourages musicians to give it a try. Guitar truss rods are actually very difficult to break, but if you are not confident or lack the time to experiment, seeking the help of a professional is still your best bet.
Before we answer the query on whether you can loosen a truss rod too much or not, we need to understand first how to adjust it.
For truss rod adjustments, a 1/4″ ‘nut driver’ wrench or allen key is required. Basically, turning the truss rod clockwise (or to the right), will make it tighter and increase the tension. Turning it counter-clockwise (or to the left), will loosen it up and decrease the tension.
Turning the truss rod counterclockwise is intended to correct an overbow (neck is arching upwards), while turning the truss rod clockwise will correct an underbow (neck is arching downwards).
What happens when you loosen a truss rod too much?
Turning a truss rod clockwise and loosening it is not as harmful as increasing the tension by tightening. Loosening the truss rod means you are allowing the neck to relax, but that doesn’t mean the outcome will be desirable.
A convex neck bow is the result of excessive tightening and this will set your guitar’s action too low, which will eventually cause some unwanted fret buzz. On the other hand, if you loosen a truss rod too much, you will get a concave bow and the action will be too high.
Technically, you can loosen a truss rod without instantly destroying your axe, but you will risk making the guitar action height unusually far from the fretboard. This is an inconvenient setup that will definitely hurt your fingers, as well as your instrument in the long run.
Keep in mind that truss rod adjustments are only necessary when there are some much bigger corrections that bridge saddle alterations can’t handle. Loosening a truss rod too much can only create more problems for you, so always keep in mind to avoid overdoing it and turn it in tiny increments, since very little adjustments can create a lot of change for your guitar’s neck.