How to Crown Guitar Frets with a FretGuru Dagger 2.0 Fret Crowning File
So you’ve leveled your frets with a leveling beam like the FretGuru Ultra-Precision Fret Sanding Beam and now it’s time to reshape the frets to precisely re-create the rounded fret crown for exceptional intonation, tone, playability and aesthetics. A common tool that most pros use for this task is a Fret Crowning File. Hopefully, your fret crowns aren’t extremely flat after a fret level. The FretGuru Dagger 2.0 Fret Crowning Files are an excellent choice to help you reshape them to perfection!
In this post we’re going to detail how to use a Fret Crowning File effectively so you can achieve meticulously shaped frets that enable super-precise intonation. We’ll specifically detail the steps using our FretGuru Dagger 2.0 Fret Crowning Files and Diamond Dagger 2.0 Fret Crowning File – which have taken years to develop, and they deliver on our promise to craft the most advanced, simple to use fret crowning files ever created.
We believe you'll find it's very simple, almost automatic, to use any of the FretGuru Fret Fret Crowning Files.
Additional Materials
Low-tack painters tape will help protect the fretboard.
While there are no sharp edges on any of the FretGuru Dagger 2.0 crowning files, as you learn to use yours we recommend protecting the fretboard around the fret you’re working on with some low-tack painters tape.
The Ideal Fret Crowning Position
Ready to get into position?
For the best results that won’t hurt your wrist, we recommend holding the Dagger 2.0 Fret Crowning File with your:
palm facing down, with the end of the handle embedded into it.
body and guitar positioned so you don’t have to bend your wrist sideways.
pointer finger resting on the top middle of the handle just behind the main filing surface and your thumb resting on the side of the middle of the handle.
middle finger gripping lighting on the bottom middle of the handle against the transition curve, with your ring and pinky fingers gripping lightly on the back of the handle.
If you’re using the spot leveling section on the back of the Diamond Dagger 2.0, the same general grip advice applies.
Pro tip: For extra fine spot refinement, you can also use it like a pencil with your thumb and middle finger gripping the sides and pointer finger gripping the top.
The Ideal Fret Crowning File Motions
You’re effectively trying to taper the top of the fret crown tightly into a thin line while maintaining a rounded profile on the sides. The good news is that FretGuru Dagger 2.0 files easily accomplish this for you, with a minimal amount of observation and guidance from you.
It’s unnecessary to push hard. Allow the file to do most of the work. You just need to lightly give it directional momentum like a train on a track. (Bearing the mind the Diamond Dagger 2.0 cuts in both directions, while the Dagger 2.0 cuts only on the push stroke).
To start, give a few mindful and consistent-yet-light full swipes, to see how the top of the fret crown is initially tapering in. What you ultimately want to aim for are thin crown tops that are at most .5mm / 1/64th” wide – as you get used to using the file you’ll find it possible get crowns well under half that width, for extra fine intonation and buttery playability.
Be especially mindful of the ends of each fret. Do your best to match the filing angle with the basic fingerboard radius, being especially careful as the file exits the fret ends. Avoid filing the ends of a fret at a steeper angle than the radius of the fret, as you can carve away lots of fret material by accident (including the top of the fret crown we need to preserve).
Get familiar with how the file glides along the top of the fret and how you can slightly adjust your angle to cut exactly where you expect to. It may take a few passes to get used to, but you’ll quickly be able to get a sense of it. The goal is to leave as thin a crown center line as possible, without grinding through it.
We’ve found it can be helpful to visually and mentally divide each fret into 8 sections. With this technique you can think of the area near the fret ends, as the outer 1/8th of the fret, which you’ll want to refine last.
As you continue to file with nearly full-length strokes (being mindful of the fret ends), you may begin to notice certain sections of the fret crown are already thin while others are still wide. This can result from an uneven (lumpy) fret installation, or during the fret leveling process, where the thicker sections were higher, unlevel sections). At this point, begin to think of the middle 6/8ths of the fret in 1/8th sections that you’ll hone and blend together before reverting back your final full-length strokes, if needed.
With both the Dagger 2.0 and Diamond Dagger 2.0 you can also rock the file side to side slightly, and use the nose of the file to focus on tapering and blending these sections specifically. With the Diamond Dagger 2.0 you can also flip to the curved spot-leveling section in the handle for extra-precise placement, which is especially helpful on upper frets of guitars where the back can’t be removed.
A Few Extra Tips
The refined cutting surfaces on all the dagger variants should leave a relatively smooth chatter-free finish that makes for less time to polish smooth and shiny.
If you are seeing light chatter marks with the non-diamond versions, lighten the amount of pressure you’re using. If you chatter, a few light swipes usually resolves it.
You should clean the cutting surface of the file every few frets or when you can tell the fret filings have clogged the channels leading to less effective material removal (you’ll feel the difference)
To clean the file, use a few swipes side to side with a brass wire brush (not lengthwise) to clear out debris and then follow up occasionally with some of your preferred protective oil.
While the Original Dagger 2.0 (non-diamond) files are made from tool steel of exceptional quality, it’s important to occasionally clean and apply protective oil to the full surface of the file to help resist rust and corrosion of the handle.
The fret sizes on the dagger are ultimately guidelines. Feel free to experiment. When using the larger side, we sometimes like to switch to the smaller side for really refining the thin line at the top of the fret.
The Dagger 2.0 files work best with frets that are at least ~.030” tall. When frets make it down to ~.025” it’s usually time for a refret.
Don’t know how to check? Our handy Precision 8-in-1 String Action Gauge has specifically designed fret wear / fret height notches to measure from ~.025” to ~.055”
Words of Caution
*While the FretGuru Dagger 2.0 crowning files are effectively fool-proof without impeding your ability to get excellent results thanks to the D.I.A. geometry, be mindful when working with them. We don’t believe in needing safety zones with our file, but it’s possible to file away your crown at the top and make your fret unlevel – although you’d have to be exceptionally careless to end up there.
What About Sharp or Unrounded Fret Ends?
Don’t worry, we didn’t forget sharp/unrounded fret ends or fret tang sprout! Before moving on to polishing the frets, we recommend using the FretGuru Ultimate Fret End File. Go visit our instructional in a new tab (Coming soon!).
Need additional help?
If you have any questions, we’re always happy to help further! Just email us at support@fretguru.com and Bernie or one our experts will be happy to work with you on your specific situation the best we can.
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Purchase Your Own FretGuru Dagger 2.0!
You can learn more about and purchase your own FretGuru Dagger 2.0 Fret Crowning Files here on our website or on our Amazon webstore using the modules below.
The latest Dagger 2.0 file is the most advanced and accurate guitar fret file ever created, and the first crowning file worthy of being a FretGuru.
Avoid deep scratches in your frets and fingerboard with the FretGuru Dagger 2.0's precisely shaped, sharp cutting teeth and smooth file edges, that give you total control, cutting accuracy and safety.
A precision tool designed to deliver exceptional fretwork results. Crafted with from high carbon European steel, which is heat treated and hardened to extreme levels, this file ensures smooth, clean, and accurate fret crowning, with superb control of your fret centerlines.
With the exclusive D.I.A. (Dual Integrated Arc) geometry, and the unique dagger-shaped profile, this allows for precise shaping and crowning of frets, enabling luthiers and guitar technicians to achieve impeccable fretwork with ease.
Now available in 2 sizes:
The original Dagger 2.0 MD/LG/XL covers fret widths in the range of ~0.085” to (barely) ~0.110”. If you’re doing vintage or 6105 frets, this is the file to get.
The new Dagger 2.0 LG/XL/XXL covers fret widths in the range of ~0.095” to ~0.118”+.
This is the file if you’re doing “modern” electric guitars. This size is also ideal if you have ~0.110” frets that have been significantly worn or leveled, in which case the XXL side is able to take a wide enough “bite” of the fret, in order to bring the sides in to a more clearly defined fret centerline.
**Both file sizes share the same LG/XL/6100 side**
Whether you're leveling, crowning, or shaping frets, the FretGuru Dagger 2.0 file is an indispensable tool for achieving professional-grade fretwork and maintaining optimal playability.
Looking for a FretGuru Dagger Crowning File with a Diamond cutting surface and an additional curved side that makes spot leveling and upper fret crowning even easier? Explore the new Diamond Dagger 2.0 Guitar Fret Crowning File, featuring the same advanced geometry as the original with a diamond cutting surface that many luthiers and guitar techs prefer.
*Box graphic is for illustrative purposes only.