Fret buzz is that rattle or zing you hear when a string vibrates against a fret instead of ringing clean. It is one of the most common things builders run into after a first setup, and the good news is that almost every cause is something you can find and fix yourself in a few minutes. This guide takes you from the symptom to the cause to the exact fix.
Applies to: every Guitar Kit World electric guitar kit, bolt-on and set-neck, with any bridge type. Fret buzz is a setup issue rather than a kit-specific one, so the same diagnosis works across all of our builds.
Find the cause
Fret buzz almost always traces back to one of a few things: neck relief, string action, the nut, or a single high fret. Play slowly up each string and notice exactly where the buzz shows up. Then use the table to jump to the right fix.
| Where the buzz shows up | Most likely cause | Go to |
|---|---|---|
| Everywhere, on most strings and most frets | Action too low overall, or too little relief | Fix 1, Fix 2 |
| Only the lower frets (open to around the 5th) | Too little relief, or a slight back-bow in the neck | Fix 1, Fix 5 |
| Only the upper frets (past the 12th) | Action set too low, or a high spot in the frets | Fix 2, Fix 4 |
| Only one string, at one spot on the neck | A single high or uneven fret, or that saddle set too low | Fix 4, Fix 2 |
| Only the open strings | A nut slot cut too low | Fix 3 |
Make one change at a time, tune back to concert pitch, and play the neck again before you touch anything else. Chasing two variables at once is how a small buzz turns into a long afternoon.
Here is a full walkthrough of finding and clearing fret buzz before you start.
Two quick checks first
Before you adjust anything, rule out the two easy causes.
- Old or dirty strings. Strings build up a film of grime and oil over time, and that alone can cause buzzing and dead spots. If your strings are old, put on a fresh set before you diagnose anything else.
- Fretting and picking technique. Fret with your fingertip just behind the fret, not on top of it and not far back in the middle of the space. Aim to push the string down into the gap between the fretboard and the fret at roughly a 45 degree angle, and ease off if you are strumming very hard. A clean fretting hand removes a surprising amount of buzz.
If the buzz is still there with fresh strings and clean technique, work through the fixes below in order.
Fix 1: Set the neck relief
Neck relief is the tiny amount of forward bow that gives the strings room to vibrate. A guitar neck should never be perfectly straight. With too little relief the strings sit too close to the frets and buzz, most often across the lower and middle of the neck.
To read it, hold the low E string down at the 1st fret and the last fret at the same time so the string becomes a straight edge, then look at the gap around the middle of the neck. You want a small, even gap of about 0.25 mm (0.010 in).
If the gap is too small or the neck looks dead flat, add relief with the truss rod. Using the hex wrench from your kit, turn the truss rod nut counter-clockwise to loosen it, which lets the neck bow forward a little. Move it only an eighth to a quarter turn at a time, tune back to pitch, and check again. Most buzz that shows up across the lower and middle frets clears up right here.
The full procedure, with the tap test and every turn direction spelled out, is in the Final Setup module.
Fix 2: Raise the string action
Action is the height of the strings above the frets. Set too low, the strings buzz, and this shows up most on the upper frets or spread across the whole neck.
Measure at the 12th fret, from the top of the fret to the underside of the string. A good starting point is about 2.4 mm on the low E side and 1.6 mm (about 1/16 in) on the high E side. If you are below that and buzzing, raise the action a little at the bridge, then retune and play again.
How you raise it depends on your bridge: individual saddle height screws on a six-saddle bridge, the two post thumbwheels on a Tune-O-Matic bridge, or the pivot posts on a tremolo. The Final Setup module covers each bridge type.
Fix 3: The nut (open-string buzz)
If a string buzzes only when you play it open, and the buzz disappears the moment you fret any note on it, the nut slot for that string is likely cut too low.
To check it, press the string down just past the third fret and look at the gap over the first fret. It should be around 0.010 in (0.25 mm). If the string is sitting almost flat on the first fret with no gap, that slot is too low.
A nut slot cut too low is not a setup adjustment. The fix is a new nut, or having the slots shimmed or recut by a tech. This is the one job on this list where it is worth asking for help rather than forcing it, because a slot cut too far cannot be uncut.
Fix 4: A high or uneven fret
If the buzz is on one string at one spot, or only on the upper frets, and relief and action are already correct, you likely have one or more frets sitting slightly higher than their neighbors. All of the frets need to be level with each other. Even one fret that is high, or one that has worn a small divot, will buzz.
To find it, rest a fret rocker (a small precision straight edge) across three frets at a time and rock it gently. A high fret in the middle makes it knock like a see-saw. A credit card edge works in a pinch. Mark any high frets with a permanent marker.
Leveling a fret is permanent work, so go slow and check often. In short: remove the strings, straighten the neck dead flat with the truss rod, mark the top of every fret with marker, and run a leveling beam with 240 grit sandpaper lightly along the frets until the high spots (where the marker rubs off first) come down level with the rest. Some builders also introduce a very slight fall-away above the 15th fret, though that is optional. Then re-mark and crown each leveled fret with a crowning file to restore its rounded top, working the file only in the direction it cuts. Finish by polishing the frets with 1200 grit and then super-fine steel wool until they shine.
Pro tip: if you do not have a fret rocker, leveling beam, and crowning file, or you are not comfortable with permanent neck work, this is a good job to hand to a luthier, or to practice on an old guitar first.
This video shows the leveling and crowning process from start to finish.
Fix 5: A back-bow
A back-bow is when the neck bends the wrong way, curving backward so the middle of the fretboard rises toward the strings. It causes buzzing in the lower and middle frets, and it usually means the truss rod is too tight.
The fix uses the same tool as Fix 1, in the same direction. Loosen the truss rod counter-clockwise an eighth to a quarter turn at a time, retune, and recheck the relief until the neck holds a small forward gap again. If the rod is already loose and the neck still back-bows, or the rod will not turn under light pressure, stop and ask before forcing anything.
When to stop and ask
Most fret buzz clears with relief and action, and those you can adjust all day. If the buzz will not clear once relief and action are right, or the problem is in the nut or the frets, do not force it.
Questions, or is something not going to plan? Comment below this tutorial with clear photos and we will help you right here. Your question and the answer then help the next builder too.
If you have a Guitar Kit World kit and the issue is with the kit itself, such as a missing or damaged part, email our support team at [email protected]. Include the email address you used for your purchase, your order number, and a couple of photos, and the team will get you sorted out quickly.
Start Here: Find Your Build Manual
For the full setup procedure this guide draws on, see the Final Setup: Truss Rod, Action, Intonation, and Pickup Height module.