Adjusting Guitar Truss rod and Intonation

Many new guitarists, and some old ones, too, are unaware of the significance of something called truss rod and intonations. Well, if you are one of those, stop whatever you’re doing and read this. Take it from a guy who learned it the hard way just how important they are.

Once, the band and I were performing in several cities. Different cities meant that my equipment and I were to be exposed to a variety of climatic conditions. One fine day, in an extremely humid city, I decided to practice one more time just to ensure all was in order before leaving for the venue to perform just two hours later. I took my guitar out, plugged it in, and the minute I began with a lick, I noticed something unusual. The action was clearly harder. I had to apply more pressure on the strings than usual.

I went on to practice for the next 20 minutes, and I kid you not, I was exhausted. My hand was hurting, and my fingers were screaming in agony. This was not a good sign. Something was definitely wrong with my guitar.

To make matters worse, I tuned the guitar with an electric tuner, meaning the accuracy was spot on. However, despite that, every note after the 12th fret sounded off. None of the strings or frets was able to produce the kind of sound they normally would.

“Oh, God! What am I gonna do now?”

Thankfully, the internet was there to help me out of this calamity, and just in the nick of time. too. Any later than that would have meant delivering a performance that was all over the place and effectively ending my young career as a guitarist.

What happened there?

Every guitar has something called a truss rod. It runs through the neck and is exclusively responsible for keeping the neck stiff and straight. Expose it to significant pressure, constant tuning, humidity, or temperatures, and the rod will bend. When that happens, your guitar’s neck takes a toll.

In an ideal situation, the guitar string action should be just like the one shown above in the picture. Neither too high nor too low, hence allowing a silky smooth playing experience. When the truss rod bends, it can push the neck towards the string, hence reducing the gap, or it can go the other way, effectively increasing the distance between the strings and the fretboard itself. Either way, you are sure to encounter a world full of miseries and worries.

For new guitarists, you may not be able to tell just by looking at the guitar’s neck whether it is bent or straight. There is, however, one way you can know for sure, and that is to play the strings on numerous fret positions. If you find the strings require significant pressure to play properly, the action is high (wider gap). A higher action can lead to a guitarist to develop painful calluses and be exhausted significantly quicker. It will also mean that you will need to sleep with a wrist that feels like it is shattered.

The story is somewhat forgiving on the hand if the truss rod bends the other way, however, the results are equally catastrophic. A lower action would mean that you do not have to exert pressure to play a note, but as soon as you do play one, it will create a buzzing noise. This means that somewhere along the fretboard, the string is touching the metallic fret bars, and that is causing the string to buzz. It’s a disturbing sound and one that we guitarists loathe.

So what can be done about this? Is there a way to fix it? Fortunately, there is! All you need is your trusty old Allen wrench (small), a tuner, and your sense of sight.

Adjusting the truss rod

Before moving on, make sure that you tune your guitar properly to standard “EADGBE” tuning.

Now that the guitar is tuned, it is time to visually check for any sign of upbow (concave bow) or back bow (convex bow). To do this, place your guitar on a flat surface, ensuring that the neck rests on a neck rest or something that does not damage it. As the guitar remains flat and straight, sit down until the neck of the guitar is at your eye level. Look down the neck and pay special attention to the region between the third and ninth fret positions. If the neck is bending downwards, you have an upbow. If the neck is coming too close to the strings, you have a back bow. To further confirm your findings, look at the guitar from the side, and this time pay attention to the gap between the strings and the neck in the same region.

Now that you have sorted that, and have established the kind of bow you have, grab your Allen key and insert it into the truss rod slot (shown in the picture below).

If you have an upbow, you will need to reduce relief. You can do that by gently turning the truss rod about one-fourth of a turn clockwise.

If you have a back bow, you must add relief by turning the rod one-fourth of a turn in a counter-clockwise direction.

Caution: Do not turn the truss rod quickly. If you feel a bit of resistance, your rod may have maxed out. Tightening it any further might damage your truss rod. If you are not sure or if you are intimidated, let a professional help you.

After the adjustment, re-tune your guitar and play. You should feel a significant difference, hence confirming that your efforts were well worth it.

The final piece of the puzzle

Now that you have sorted out the bent neck problem, it is time to learn how to tune your guitar using intonations. Remember the problem where I was not getting the right notes after the 12th fret? That is where intonations come in.

There are two ways you can tune a guitar. One requires you to use the tuning pegs, obviously, and the other requires you to fine-tune using the intonations.

How to fix intonation issues

First, play any open string on a fully tuned guitar. Then, play the same string on the 12th fret. If the note produced is perfect, you do not need to do anything, but if it sounds off, follow the easy guide here.

If the note creates a flat sound, you need to adjust the saddle towards the neck. The saddles are those little things between the pickups and the bridge. To adjust them, use a screwdriver and rotate the saddle one-fourth of a turn. Play the 12th fret after every adjustment until the flat sound is gone and the proper sound is produced.

If the note on the 12th fret creates a sharp (#) sound, you need to adjust the saddle backwards towards the bridge. Use the screwdriver with one-fourth turns in the opposite direction to make the saddle go back. Once again, play the 12th fret until the proper note is produced.

Repeat the same process for every string until all strings sound perfect when played.

Of course, the above is just a standard way of down things. It is not as easy as it sounds for everyone, and this has more to do with the fact that there are numerous types of bridges out there. Each of these bridges works and behaves differently. The most popular ones available today include:

1. Floyd rose bridge
2. Fender’s floating bridge
3. Telecaster bridge
4. Stratocaster bridge (synch tremolo)
5. Les Paul bridge (stop tailpiece)

There are many others on the market which makes the intonation adjustment slightly more challenging. If you aren’t confident, it is always a good idea to pay a visit to your local music shop and let the professional do the job for you.

What about acoustic guitars?

When it comes to acoustic guitars, you are faced with an extremely limited choice. You can either buy a compensated saddle or you can file your saddle until it gives you the desired results.

The trouble is that acoustic guitars do not have adjustable saddles. They come with a thin plastic piece resting on the bridge in a slightly tilted fashion, and that’s it. Filing isn’t my first choice, but if I have a few spare ones, I wouldn’t mind experimenting a little.

For best results, consult a technician who can assist you with the adjustments.

Bonus tip

If humidity and temperatures are bothering you a lot, and you are hoping not to tweak your truss rod now and then, you can always grab yourself a guitar with a roasted neck. It is essentially wood that is roasted, drying out all the moisture and oil. It is more reliable and can last a long time before requiring any rod adjustments. It is much more effective, and it looks cool, too.

Regardless of which guitar you own, knowing about intonations and truss rods is essential. By learning how to do this yourself, you are saving yourself a fortune in the long run. While there are guitar professionals out there, it is not always feasible to approach them, especially if you are on the move and have a gig in the next few hours. Do it safely, and enjoy the rest of the experience.