DIY Guitar Set-ups: Part 1

Adjusting the Truss Rod


Stephen Barker

2021-05-23 4 min read

Truss Rod Adjustments in 6 steps

1/ Before you start turning that nut this way and that, you need to know WHY you are going to make the adjustments. There are three main reasons why you would want to touch your truss rod. A/ There is a big gap between the stings and the frets, with a visible 'up bow' in the neck. B/ The neck is flat or has a 'back bow' causing the guitar to 'fret-out' or buzz a lot.
It's really important to know which, if any of these things are the problem. I've had so many guitars brought into my workshop because people have not followed these basic steps.

2/ You will need the correct tools for the job. I cannot stress enough how important this is. Some guitars use an Allen key or a box spanner. It is essential to use the correct size tool as stripping the adjustment nut is just going to make things a whole lot worse. Other tools that are useful, but not essential: straight edge, feeler gauges, capo, torch. If you have the User Manual for your guitar, locate the information about specific tools before you move on to the next step.

3/ Adjustments should be made with the guitar at pitch. For the best results, if you use this instrument for E standard tuning, the guitar should be tuned to E standard. If you use this guitar for drop D, tune it to drop D. Truss rod adjustments are all about relative tension. The strings and their tuning is part of that balancing act. If you use one guitar for several tunings, you will need to experiment to see which works set-up works for you best.

4/ Locate the truss rod adjustment nut at either the head or heel end of the neck. You will find it on many electric guitars at the head end, but on some older electric guitars (especially old Fenders) the adjustment nut is located at the heel end of then neck meaning the neck will need to be removed before you can make adjustments. Here you will need a straight edge and you will need to calculate compensation as there is only tension from the truss rod, not the strings. There is a lot of trial and error in setting this kind of truss rod adjustment.

On Acoustic guitars the adjustment nut can be either end of the neck. If it's at the head it will be behind a cover. If its at the heel end, access is through the sound hole. Use a torch to locate and check the type and condition of the nut.

When the adjustment nut is at the head end, it is either accessed through a small aperture - these usually have a female nut and require a hex key (Use a torch to locate and check the type and condition of the nut). It's essential to use the correct type of key. Usually Fender and Gibson guitars have 'Imperial' sizes, while Squier and Epiphone usually have 'Metric' parts. This info should be in your user manual.

5/ Now you've located the adjustment nut and determined if you need an imperial or metric tool and the correct size for your guitar, you should ensure the adjustment nut isn't seized. To do this stand the guitar with the adjustment nut pointing up wards. drop a little light machine oil around the nut and leave it a few minutes to work it's magic. You won't need much, just enough to work through the thread.

6/ If your guitar has buzzing frets between the 2nd and 15th fret, you want to add relief to the neck. To do this release the truss rod or turn it anti-clockwise as you face it. If the strings are too high, you need to reduce the relief. Tighten the truss rod by turning it clockwise as you face it. With truss rods you really need to take your time. Be gentle, don't force it. If the truss rod doesn't want to move in the direction it needs to, leave it a little longer for the machine oil to do its work. Once you're sure the nut isn't seized, make small 1/8 or 45 degree turns and check the guitar. In my experience around 90% of the movement that's going to happen, happens right away.

To check the adjusted relief use one finger of your left hand to fret the 6th string at the first fret and your little finger of your right hand to fret the same string at the 12th fret. Now tap the string at each fret with your free digits. There should be a gap not much more than a sheet of paper at the 2nd and 14th frets. The gap should be greatest around the 6th and 7th frets. You can use a capo (or 2) to make this job a lot easier.

How does it play? If it plays comfortably without chocking-out or buzzing, job done! Some high quality guitars give detailed specifications for set-ups and will give pretty precise measurements that require feeler gauge measurements to be taken at certain frets.

If you find it buzzes all over the neck, you need to add more relief. If it's pretty much right but has one or two buzzing frets, you may need to level your frets.

Powered by