Neck radius and action setting question

[Cymbaline]

I'm wondering how to set the action at the bridge.  My Warmoth neck is compound radius, 10-16", so what should the radius be at the bridge? 
I downloaded a neck radius gauge template here
http://www.pickguardian.com/pickguardian/Images/Pickguardian%20Neck%20Radius%20Gauges.pdf
and was going to use the 16" gauge, but it occured to me the radius should be flatter up at the bridge than at the end of the fingerboard.  Should I use the 20" gauge maybe?

 

[GoDrex]

I've read it's like 18.4 ...  anyone know for certain?

 

[blue313]

Yeah GD, I'm pretty sure Gregg said at one point in time that it was 18 ish but I can't find it.  Then again, anything past 18 is not much of a difference.  I set mine to 18 and its got fantastic action.

 

[DocNrock]

I've found a great guitar guy in town who can work what seems to be magic.  I build them, and I take them to him without strings attached.  I get them back, and they play like butta.  FWIW, he has had to do a fret leveling on 2 of the 8 Warmoths I have taken him.

 

[Cymbaline]

I wound up using the 20" gauge and it plays great now.  :headbang:

(Don't have a 18" gauge.)

 

[T.L.]

That 's a bit of a strange way to set action...

 

[CarteBlanche]

As I remember  it was 18.5. But only your fingers can tell you when it's right.

 

[tfarny]

Well you'll need to get your high and low E at the right heights first. I then try for 16" radius, and follow up by going string by string to get them as low as I can without too much annoying buzz. If you spend some time on it, and maybe tweak it several times, you'll get there eventually. You will have a hard time seeing or even measuring the difference between 16 and 18.
One question I've always had about compound radius: doesn't a flattish bridge radius make the middle strings' action too low at the first few frets, where the radius is only 10"?

 

[GoDrex]

seems to me if the nut is cut right the strings should follow the shape of a cone as you go down towards the bridge. If the nut is around 10" and the bridge near to 16 or 18 the strings would gradually flatten out - just like the neck.

 

[simple]

As I remember  it was 18.5. But only your fingers can tell you when it's right.

Correct; 18.5.  Some people can just tell when its right and some people not so much. A radius gage is a great place to start.

Of of the guitars I have built, I have had the best initial "out of the box set ups" with the compound radius necks. Whether it was a Wilkinson trem or a Tune-o-matic bridge, that has been my real world experience so far.

 

[Ang3lus]

how do i get a 18.5" radii gauge ?
:/

 

[blue313]

I doubt you'd find one, it's easy enough to make  :dontknow:

 

[Ang3lus]

how ?
:[
i'm KINDA bad @ math

 

[blue313]

The "Radius" of a guitar neck is the same curve of a circle that has a radius of whatever you're looking for.

Take a piece of string and attach a pencil to one end.  Measure the string to 18.5 inches, hold the non-pencil end down and draw an arc on a piece of paper.

 

[Ang3lus]

oh
i see
thanks.
should be easy enough