How to Fix Uneven Frets

If you are experiencing fret buzz (your strings are coming into contact with the fret wires as the strings vibrate) aside from your neck relief being insufficient, or your action just being too low in general, one of the main causes of fret buzz is uneven frets. Uneven frets can also cause intonation problems, a lack of sustain (particularly when bending notes) and create dead spots on your neck.

While low action or poor neck relief can be responsible for many of these problems, when it comes to fret buzz uneven frets are normally more isolated e.g. you play the 5th fret A on your high E string but the fretwire on the 6th fret sits higher than the 5th, resulting in the string buzzing the fret wire.

In some cases the frets may be worn in one area from regular playing, in other cases you may have a loose fret or the fretwork is simply uneven.

In the following article, we're going to discuss how to fix uneven frets, otherwise known as fret dressing, which is the process of levelling, crowning, and polishing our guitar’s fret wires.

First we’ll identify uneven frets on your fretboard and level the frets using a fret levelling beam. Once our frets are level we'll then dive into crowning and finish up by polishing our guitar frets to ensure our strings glide across the fret wires easily when bending the strings.

A Word of Caution
Before you follow any of the steps outlined below, keep in mind you can really mess things up here by removing too much material. If unsure or you don’t have the tools listed below take the guitar to a luthier, or practice on an older guitar first.

Tools Required

• Guitar neck rest
• Notched straight edge for measuring neck straightness
• Hex key (allen wrench) for truss rod adjustment
• Fret rocker (optional)
• Levelling beam and/or shorter fret file for spot levelling
• 240 grit sandpaper & double-sided tape
• 1200 -1500 grit sandpaper
• Crowning file (or 3 corner file)
• Super-fine grade steel wool
• Painter's masking tape
• Fret guards (optional)

Fret Leveling

Identifying the problem

Your frets should all be level, with the exception of your upper frets (from the 15th fret) due to the oscilation of the strings relative to the reduced neck relief the higher up the neck we venture.

The diagram below shows this in more detail.

As we can see, the movement of the strings is greatest near where the fretboard ends. To address this particular issue upper fretboard fallaway is employed e.g. the last 5-7 frets reduce in height as we ascend further up the neck, with more emphasis placed on the bass strings due to the greater mass of the strings and larger arc.

Disassemble the guitar / remove the strings

Unless you are working on a new kit guitar and are yet to install the neck or any of the electronics and hardware we’ll need to remove the strings before we can level the frets.

Some people also remove the nut at this stage which you can do if you are upgrading the nut, however it’s not strictly necessary. However, do protect the nut by covering it with masking tape.

If your guitar has a bolt-on neck, I’d recommend removing the neck from the body completely, purely for ease of use and to reduce the chances of file shavings becoming stuck to the pickups (they are magnets after all). If your guitar has a set neck you may want to mask off the electronics and pickups to prevent this occurring.

Check for loose fret ends

It’s a good idea at this time to check for loose fret ends. Frets can become loose due to changes in humidity or from impact.

To check your frets take a section of wood and press down on the frets checking for any movement, particularly the ends of the frets. If you notice movement, mark the loose fret with a permanent marker and move onto checking the rest of the neck.

In my experience, I’m yet to work on a kit guitar from guitarkitworld.com that had this problem but if so, the frets will need to be glued into place using superglue and clamped.

Straighten the neck

Next we need to ensure the neck is straight. This is essential as we can’t accurately level our frets if the neck has too much relief (e.g. it bows inward).

If the neck isn’t straight you will greatly increase the chances of removing too much material on the lowest and highest frets where the relief is less prominent. If this does occur, in the majority of cases the frets affected will need to be replaced, which requires the skills of a luthier.

First, remove the truss rod cover (if your guitar has one) and turn the truss rod clockwise using a hex key (Allen wrench) if you need to introduce tension to the neck and reduce the amount of relief.

Next, measure the straightness of the neck using a notched straight edge. Using a standard steel rule here won’t be as effective as the ruler will sit on top of the fret wires. Your notched straight edge will have two sides, one for 24.75” scale length (Gibson® style guitars) and one side for 25.5” (Fender® Style Guitars) scale length.

Use the appropriate side for your neck and lay the notched straight edge directly on the fretboard and check the neck is dead even by getting down to eye level and looking for gaps beneath the straight edge.

Check for Low Frets

Spot Levelling

Once the neck is straight, take a fret rocker and check the height of each individual fret. If you don’t have a fret rocker available, you could also use a credit card or something of a similar size with a straight edge.

Note. If you plan on levelling the entire fretboard regardless, you can skip this step and move onto levelling the frets.

The benefit of using a fret rocker is it is specifically designed to span three frets at a time. The edges of the fret rocker are cut at three specific lengths. This is to allow three frets to be compared higher up the neck as the frets become narrower.

Use the medium size edge once you reach the 10th fret and the shorter edge from approx. the 17th fret.

Once sitting on top of the fret wires attempt to rock the fret rocker (hence the name) back and forth. If there is movement e.g. you hear a knocking sound as the fret rocker comes into contact with the two outside fret wires, then the middle fret of the three is higher than the surrounding frets. (see diagram above)

You’ll need to do this for each fret, across and up the neck. Any frets you identify as being uneven should then be marked using a permanent marker. Take care to prevent ink permanently marking the fretboard (especially if Rosewood). You can also mask off the fretboard if you prefer.
In some cases you may not need to mark the entire fret as only half the fret is too high (frets can wear unevenly, especially on the treble side), if this is the case just mark the area of the fret wire affected.

Spot Level or The Entire Neck?

Next, you will need to decide whether to tackle the entire neck or spot level specific frets. For example, if you see ink residue on more than 5-6 frets, I’d recommend levelling the entire neck using a fret levelling beam.

If however, you only have a few frets affected, it is far more efficient to simply level those frets that are sitting too high.

Levelling the frets

For this step we require a levelling beam (or smaller fret file if spot levelling). The levelling beam (in most cases) will require sandpaper to be fitted to the underside. Use double-sided tape to secure the sandpaper in place. I normally use 240 grit paper.

Next take a permanent marker and mark the top of each individual fret (if you haven’t done so already).

We do this as a way of indicating low frets.

For example, if the frets on either side of a specific fret have had the permanent marker filed away using the levelling beam, but the adjacent fret hasn’t had any marker removed we can assume the fret is lower. (see diagram above).

When using the levelling beam, use the weight of the tool itself rather than applying any downward pressure and carefully run the levelling beam across the entire neck, taking care not to bump the nut if still in place.

Ideally we will level the frets by removing the minimum amount of material necessary, so be sure to check your work regularly and stop once all ink residue has been removed.

Keep in mind the taper of the fretboard (contoured fret levelling beams are also available, but will need to match the contour of your neck) and angle the levelling beam as you file the edges of the fretboard. Taper usually becomes more prominent from approx. the 15th fret on most guitar necks.

Keep in mind also, for the last 5-7 frets it’s a good idea to introduce fret fallaway. Work with your levelling beam on a very slight angle to remove slightly more material the further up the neck you go from approximately the 15th fret.

Fret Crowning

Once complete your frets will now be level, but that’s only part of the job. The process of fret levelling flattens the top of the fret wires and this creates a problem in itself.

We need the point of contact for the strings at the top of the frets (the bead) to be as narrow as possible for correct tuning. The other problem is, if the top of the fret wires are too wide we increase the chance of fret buzz occurring regardless of the frets being level. So, it’s important to reduce the surface area of the fret wire making the point of contact as narrow as possible for the strings. This process is known as crowning.

There are several different tools you can use to perform this task. I prefer using a two sided crowning file. The file itself has a channel running through the middle and is easier to use for people like myself who don’t perform this type of work day in/day out. By simply running the file over the fret wire the point of contact for the strings is reduced and in general it does a much quicker job.

But, it's not essential and you can simply use 3 corner file working away at the edges of the fret wire. The only difference is you will take more time.

Before you begin crowning however, you will need to mark the individual frets again using permanent marker. You can then check your work by observing the width of the permanent marker line until it eventually becomes a fine line of ink.

We also need to protect the fretboard before performing this task or the file may dig into the fretboard scratching the surface. You can use masking tape here if you prefer or use a fret guard (a small rectangular tool used to protect the fretboard while crowning).

To save yourself time. Don’t try to mask the entire fretboard. You will need to cut smaller lengths of tape for the smaller frets and this can be time consuming. I have found it much faster to simply mask each fret as you are working on it. This way you can work with the masking tape without needing to cut to shape as it wont matter if the frets beside the one you are working on are temporarily covered over by the tape.

When using the file, you should only use the file in the direction it cuts in. It will wear faster if you drag it backwards instead of picking it up and bring it back to starting position. Also work with the minimum amount of downward pressure required to remove material and continue to check your work until the thicker permanent marker line is reduced to a nice then edge.

Fret End Rounding

Next we need to round off the edges of the fret wires or they may end up too sharp and jag your fretting hand when moving up and down the neck.

If you take a close look at the ends of the frets you will notice a bevel approx. 1-2mm. To ensure this bevel remains in place I like to run the levelling beam (on the correct angle) accross the ends of the fret wires. You can also use a 3 corner file here, pulling the file back toward you while rolling the wrist to achieve the bevel.

Again, you won’t need to apply a great deal of pressure here, or work for very long. As you begin removing material, if you are using a file, roll the file inward to round off the edge and again, continue to check your work to prevent damaging the edge of the fretboard or removing too much material. What we are aiming for is a smooth fret end.

Polishing the frets

Our last job is to polish the frets. There will be tool marks on the frets and fret ends left over from the files after successfully leveling and rounding off the fret wires so to prevent the strings being caught up by the frets when bending a note for example, we need to ensure the frets are smooth and polished.

I generally start with 1200 grit sandpaper to do this, followed by super-fine grade steel wool. You can also follow this step with a polishing compound, and/or fret erasers if you have them available.

Take the 1200 grit sandpaper and, using your hands run the sandpaper along the edges of the frets first, running back and forth against the fretboard. The 1200 grit paper is very fine and shouldn’t harm the edge of the fretboard but you can keep the masking in place (if you used masking tape) to protect the edges during this step.

Using the same process, next begin polishing the top of the frets. The goal is to remove any scratch marks left by the files, not to remove material so check your progress regularly and ensure you are not altering the now narrower point of contact for the strings.

Follow up using the fine grade sandpaper by applying fine grade steel wool. Use the finest grade steel wool you can here, you will generally find super fine grade steel wool at your local hardware or arts and crafts store. Don’t use anything courser than this as you will undo all your hard work up to this point.
Continue polishing the fret wires until you no longer notice any marks.

Once satisfied, you have then completed the task of levelling, crowning and polishing your frets.

Recommended: Engineered Ebony Fretboards 

Summary: How to Fix Uneven Frets

I hope the information above helps you level, crown and polish your guitar’s fret wires. Keep in mind when performing this type of work, the changes you make to the neck are permanent. So firstly ensure your neck is dead-straight before commencing and ensure you regularly check your work to avoid removing too much material.