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Was curious how you all decide what fretboard radius you use for various types of guitars. Working on #2, a dred of blackwood/cedar and was wondering what guidelines people follow in choosing the FB radius. Thanks for any thoughts and guidanc.

Kevin

I do 16" on most of mine.... but I guess its up to the new owner to decide what radius is most comfortable for their playing.

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

16"

Peter and Michael, do you do 16" all across the FB or have another radius added after the 12th fret like some builders do?

I do a compound radius, (or at least I did when I wasn't retired from building) - 16" at the nut, and 20" at the other end.
This can best be achieve buy purchasing Craig Holden's Fretboard Radiusing Jig. Nice tool, well worth the money.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Interestingly I use the Stew Mac 20" radiusing block and when I have got rid of the chalk line down the centre of the fretboard, it ends up as 16" radius at the first fret and 20" radius at the last fret

By the way, if we are insisting on being pedantic (as famously happened in the "parabolic" bracing thread) shouldn't it be compound radii?

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

In theory compound radius are better, but most people don't play much around or after the 12th fret anyway....compound radius allows better bending and playability after the 12th fret.....that only if you are that type of player I stick to 16" all over the board unless a customer requests otherwise!

good luck building!

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

[QUOTE=peterm] ...compound radius allows better bending and playability after the 12th fret...[/QUOTE]
Actually, that's not quite the case. The flatter radius toward the fingerboard's end reduces that area's fret interference when playing, especially, between frets five and twelve. The effect is most noticable with low action and/or bending strings up a full step or more--neither of which is usually a concern for acoustic guitars; which, of course, is why your constant radius works just fine.

Carlon, I disagree with you on this matter.
you can find a lot of info on the wef for compound radius.

The fingerboard, or playing surface of the guitar neck, is usually curved or radiused across its width. The purpose of this radius is to accommodate the natural ergonomic shape of your fingers when they are in playing position. Comfort is certainly a major factor in selecting a fingerboard radius but it is not the only factor. Musical Style... the fingerboard radius must also allow you to play the style of music you prefer.
This retains a tighter radius in the area commonly used for rhythm and chording, while flattening the area used for bending and lead playing.

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

What you are both saying is correct ... but there is a mathematical reason as to why a compound radius works so well, especially when the lowest possible action is required. The string spacing at the nut is narrower than that of the bridge. Add in the radius of the nut and saddle, and this leads the strings to take on a cone shape. If the radius of the FB is constant, the shape produced by the FB is cylindrical - onto which you are placing strings that take on a cone shape - as the strings get closer to the cylinder FB, buzzing and fretting out while bending will occur prior to when it would on a correctly shaped compound or cone shaped fretboard. The cure for this when using a cylinder or constant radius FB is to raise the action - with a 16 inch radius board, the action raise is fairly minimal to achieve this, as opposed to say a vintage fender with a 7.5 radius board, where fairly high action is required to be able to do wild string bending up high on the FB

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

[QUOTE=peterm] Carlon, I disagree with you on this matter.
you can find a lot of info on the wef for compound radius.

The fingerboard, or playing surface of the guitar neck, is usually curved or radiused across its width. The purpose of this radius is to accommodate the natural ergonomic shape of your fingers when they are in playing position. Comfort is certainly a major factor in selecting a fingerboard radius but it is not the only factor. Musical Style... the fingerboard radius must also allow you to play the style of music you prefer.
This retains a tighter radius in the area commonly used for rhythm and chording, while flattening the area used for bending and lead playing.[/QUOTE]
Peter...I don't think we really have much of a disagreement here. Players definitely tend to have a favorite radius for comfort and style, sometimes one for acoustic and a different one for electric.

I was only suggesting the main reasoning behind a compound radius--that is to get the higher frets out of the way of the vibrating string when playing between about frets five and twelve, especially when bending. Now, that was a big problem on early Fender electrics with their 7 & 1/4" radius--players wanted light strings with low action, but when they tried to bend, the string would "fret out" as it climbed the hill toward the center of the fingerboard. As is often the case, repairmen came up with a solution. They started putting a compound radius in the frets by flattening their arch as they got higher up the fretboard. On a refret, they'd adjust the board itself. Players liked it and small builders started offering a compound radius as an option. Fender finally caught on and started building with a flatter overall radius.

I don't think all this makes that much of a difference in a properly set up acoustic. The action is higher and the bending is usually not as extreme. I think here, it comes down to player preference. Gibson often used a straight 12" radius on their acoustics, and modern Martins and others have been generally around 16 or 20", and they're all perfectly playable for most styles.

[QUOTE=TonyKarol] ... but there is a mathematical reason as to why a compound radius works so well, especially when the lowest possible action is required. [/QUOTE]
Yep, the math explains why it works, but I bet players and luthiers only became aware of it after they'd started using the compound radius.

16 radius, no compound

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Andy Z.
http://www.lazydogguitars.com

For those that do a compound radius, what do you do with leveling the
frets??

Do you compound level them????

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Andy Z.
http://www.lazydogguitars.com

i like to use 15.456 radius at the nut, and 19.234 at the fingerboard end

paddy

[QUOTE=Dave White]By the way, if we are insisting on being pedantic (as famously happened in the "parabolic" bracing thread) shouldn't it be compound radii? [/QUOTE]

I stand corrected !

   

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Andy, you level them just like you do on any other fingerboard. I use a flat bar and sandpaper.

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Tickle your guitar daily, and it'll tickle you back.

So...if the main purpose of the compound radius is meant to give more action room higher up on the board, do the bridge and saddle need to be set up as if the FB was one constant radius? (Thereby giving greater distance between the strings and frets as you go further up the neck).
Tony, I like your explanation of cylindrical vs conical. That`s the way I saw it after looking at a violin FB.

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Give me 50 cents worth of regular.
Check my oil too, if you don`t mind,,,

I realize there are reasons as far as playability for using compound radii (but Dave, isn't that redundant?), but my reason is more simple than that. When I use the compound r, I get a uniform thickness on the edge of the fretboard with the same thickness in the middle the whole length of the fretboard.
For me, it's cosmetic too.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Don,
Now I know why your guitars always looked so good, (that is before you retired} you really watch the details.

I do a compound also - 16" to 20". I just got Craig's jig, and WOW! What an awesome tool! Absolutely beautiful craftsmanship! Thanks Craig!

-Mark

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Pullman, WA

The more I know, the more I know I don't know.

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I find that as far as compounds go, the most common seems to be 16"-20". I've made guides as tight as 7.25" and as flat as 30", (not that they use this range on one guitar) depending on the feel folks are looking for and the type of guitar they are building.

Thanks for the nice comments Don and Mark. (And thanks for being so patient Mark! I did start on the next jig as promised! )

Craig