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I just leveled and crowned the frets on an electric guitar. I was pleased with the level and polish but I have some concerns about the crown. Is it possible to not crown enough and get a slight buzz. How much crown is needed? It almost seems like there is a very slight buzz...maybe a little like a fretless bass "growl". It seems to be more dominant on the higher strings that are not wound. (E, B, G).

Any ideas?

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Brad
Avon, OH

I suppose it could contribute, but it would have to be a pretty flat crown to cause the problem you describe. I've seen some pretty flatly leveled / poorly crowned frets, where intonation can suffer and buzzing may work in as an issue in extremely low setups. Still, in it's not really that common a symptom of a poor crown. I'd look more to the leveling, setup, and saddle condition if I were you. For the fret crown to cause that symptom they would have to be pretty much dead flat on top - even a slight roll or bevel off of center would keep this from occurring.

Could you describe your leveling, crowning, and polishing process a bit?

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Eschew obfuscation, espouse elucidation.

First the amount of crown is not causing the buzz. If the buzz is fret induced, the fact the fret is fully radiused or partially radiused has nothing to do with the cause. If a fret induced buzz then there is a high spot on the fret, frets or the set-up is out.

Now to how much crown radius. When I crown my frets I draw a sharpie line on the length of the rough dressed fret. I crown till the line is gone everywhere. So I put a full radius crown. Anything less you are shortening the fret position by half the width of the flat left on the fret

Here is an example of what I said

There are many ways to get to the same place. I like to leave a slight line during crowning, as I think it ensures a more accurate plane on top of the frets. The line and those two little corners get removed during the next step, which for me is sanding with 320 grit w/d.

I also agree that the buzzing would be most likely a result of the setup and not fret crowning. How low is your action? How much relief?

I do it the same way as Barry, leaving a line about 1/64" wide at the most uncrowned down the center of the fret. If you lose that line, it's easy to start taking the frets out of level. Sandpapering the frets next removes the scratches and smoothes everything over, but shouldn't take the frets out of level.

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Mike

"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there. The Dude. Takin' 'er easy for all us sinners. Shoosh." The Stranger

Good points. Here are a few clarifications...

The buzzing is very consistent up and down the neck. This leads me to believe that this is not a function of a few low frets.

Like others, I also leave a very thin line (sharpie) in the middle of the fret when crowning to ensure I remove the sides and not the top.

There is a good chance that this issue is a function of the action being too low. I have a few more adjustments to make and this should help. I will let everyone know what I come up with.

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Brad
Avon, OH

if you buzz at all note positions up and down the scale the the fret levelis not the issue. First place to look would be action.

A to be clear when I crown till the ine is gone I mean till it is just gone or consistantly hair thin, .005" or so . Personally I feel 1/64" flat being left till polishing leaves you open to being .007" out of scale on each fret. does not sound like much but can cause temperment issues. .007 would not likely be very auditably out but after fret wear would become pretty quick. But as long as when you are finished the center of the fret is the highest position and the only high position then you are in scale. I think most are saying they leave a bit of flat and end up polish the flat out thus leaving the center of the fret as the only high spot with no flat left.

This makes sense.

Here is an additional question to all:

How much relief in the neck is ideal?

I know this is a trick questions but most of my experience is from setting up basses. At this point I am developing my expertise on guitar setups which are similar but seem to have some unique differences.

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Brad
Avon, OH

String gauge, String tension, scale length, string clearance and attack all play a role in this so there is no single answer. But to simplify, enough to account for string oscillation at a given attack at a given set-up is min.

Brad ,
If you are using .10-46 or 10-42 guage strings and scale is 25.5 or close, try this.
A good place to start is hi E 3/64"+ low E 4/64" between string and fret @ 12th fret,with the string held down at the 1st fret.
As for relief ,start with .005"at fret 7 and use more or less if you need to.
Try measuring the relief holding the string down at fret 1 with a capo and fret 12 with a finger
That takes any fallaway out of the works.
Is the buzz present when fretting the highest note?
If so then you have a saddle issue not a fret issue.
hope that helps, good luck

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How long is that in luthyears?

Enough that when playing a freted string, the non-played portion of the string (the part between the fretted part and the nut) fails to vibrate against the frets.

That's all. Whate'er amount of relief it takes to get rid of the backbuzzis sufficient!

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-donh-

Everything is a tone control!