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Quick question, and I think I know the answer, but not sure. What is the difference between the fretboard radius and the top/back radius? Top/Back uses "feet" radius, so a 25 foot radius is basically a 25' diameter ball and a cut out section of the bottom of the ball. But a fretboard radius is in inches, is this correct? So a 12" radius is the same as a small cutout section of a 12" diameter ball? It just seems that the radius is much greater when you talk in inches, but a fretboard radius doesn't look that curved.
Tracy

Your correct -

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Lance@LuthiersForum.com

No, not correct.

Diameter = Radius x 2

So, a 12" diameter ball would have a 6" radius.

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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."

NO! Wait...don't sand that fingerboard radius yet!

A 12 inch radius would be cut from a 24 inch diameter ball, or circle. A cut from a 12 inch diameter ball would give you a 6 inch radius. Radius is from the center of a circle to the perimeter, or 1/2 the diameter.

Thanks Hank, so if that is true, then a guitar top that has a 25' radius would have been a radius from a 50' diameter ball?

Yep. The back and top are the surfaces of a sphere (or ball) with a pretty darn huge diameter (twice the radius), measured in feet, but the fingerboards are sections of a cylinder (single radius) or a cone (compound radius) measured in inches (and again, diameter = twice the radius). If you look at a fingerboard head-on, you can plainly see the curve over a span of less than 2". Look at a 2" wide piece of top or back, and I challenge you to see any curvature at all.Mattia Valente38447.6971643519

Thanks for clearing that up Mattia. Makes sense!

What Mattia said.
Tops and backs are HUGE radii items.

Um - ya what he said!

Actually I've always thought it was part of a smaller ball - I stand corrected

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Lance@LuthiersForum.com

Lance, I think you are thinking about the smaller radius top that results when the drum player wraps an ovation around a heckler's neck. Or something like that.

WAIT-it's a piece of pie X the radius of the plate squared.

[QUOTE=bob J] WAIT-it's a piece of pie X the radius of the plate squared.[/QUOTE]


CAKE????

Pudding...How can you have any pudding if you don't eat your meat.......pie R square.....Just another birick in the wall other wise known as the area a circle

Not if you measure in cubic furlongs per fortnight!