making a nut for a compound radius neck

Discussion in 'Luthier's Guitar & Bass Technical Discussion' started by Ang3lus, Oct 15, 2008.

  1. Ang3lus

    Ang3lus Member

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    I currently have a 12" tusq nut on a 10"-16" radius neck, and obviously i get some buzzing and hard to get correct intonation, do i need to file down the nut to be 10" radius ?
     
  2. Eagle1

    Eagle1 Member

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    Yes:AOK
     
  3. Ang3lus

    Ang3lus Member

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    sanded it down
    works perfectly now
    no buzzing with open strings and intonation is superb
    thanks :D
     
  4. David Collins

    David Collins Member

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    Each slot should be cut and judged individually, in which case the radius does not really factor in at all.
     
  5. Eagle1

    Eagle1 Member

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    Which in this case will match the first fret 10".
     
  6. clamdip7714

    clamdip7714 Guest

    Send a email to Brian over at Warmoth. He is a guru when it comes to nuts, especially on a compound neck.
     
  7. Eagle1

    Eagle1 Member

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    To say what exactly?
    The nut must conform to the first fret period.
     
  8. Curly

    Curly Member

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    I agree ... to be more specific, the radius at the 12th fret has no effect on the radius at the first fret and the nut
     
  9. David Collins

    David Collins Member

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    Well, maybe... It will probably be so close as to make any difference insignificant. Sorry if I get stuck on these tiny theoretical differences. :eek:

    My point is though, that there is no point or reason to even contemplate the radius in this case. Each string height is best judged and adjusted independently, in which case each is in it's own plane and can be adjusted entirely ignorant of any radius at all.
     
  10. Bob V

    Bob V Member

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    Try looking at it this way: you are basically setting the nut slot depth near enough to the radius of the first fret, but you might like to have progressively more relief on the bass strings. That way you wind up with nut slots that do not strictly follow any set radius.

    If you follow the basic Stew Mac trick of stacking a few feeler gauges on the fingerboard to act as a stop when you file the slot, then you wind up following the fretboard radius plus the thickness of those gauges. Now if you cheat the bass string slots up a bit and use progressively higher stacks of gauges then you're not really following the fingerboard radius anymore, it's just a starting point. And of course if you know what you're doing and you cut the slots by eye and feel (not me, yet) then you aren't measuring with a ruler or gauge anyway.

    By the way, Ang3lus, what do you mean by "sanded"? did you use nut slot files?
     
  11. Eagle1

    Eagle1 Member

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    :aok
     
  12. Kingbeegtrs

    Kingbeegtrs Senior Member

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    if the compound radius is 10-16 you should have the nut radius set to 10" and the bridge radius set to 16" A compound radius is a conical radius...which means that it starts at 10 and ends at 16. A guy at Warmoth explained that one to me.
     
  13. Ron Thorn

    Ron Thorn Gold Supporting Member

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    I believe the 10-16 radius on a Warmoth neck is the fretboard itself. The Bridge will be set to an approximate 20" radius.
     
  14. GuitslingerTim

    GuitslingerTim Member

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    The distance from the nut to last fret on a 22 fret, 25.5 inch scale guitar is 18.25 inches. If the difference between the radii of the fingerboard is 6 inches (10"-16"), the progressive change in the radius is (18.25 / 6) a one inch increase in radius for every three linear inches of fingerboard. With that ratio established, the distance from the last fret to the saddles on the bridge (7.25 inches) can be divided by three and added to 16 to arrive at the ideal saddle radius: 7.25 / 3 = 2.4 : 16 + 2.4 = an 18.4 inch saddle radius, which is the reason a bridge or tremolo with individual saddle height adjustments is necessary when using compound radius fingerboards--no one makes a bridge with an 18" saddle radius.
     
  15. Kingbeegtrs

    Kingbeegtrs Senior Member

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    Set it to whatever feels best to you.
     
  16. Eagle1

    Eagle1 Member

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    Every strat style bridge is adjustable to any radius,only the Floyd is fixed and you can shim that to 18" no problem:huh.
     
  17. GuitslingerTim

    GuitslingerTim Member

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    There are other choices for bridges beside what is used typically on a strat, like tuneomatics, and other hardtail bridges with fixed saddle radii.
     
  18. Eagle1

    Eagle1 Member

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    True but not many get used on strat style guitars.
     
  19. Kingbeegtrs

    Kingbeegtrs Senior Member

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    how many people use the compound radius? Every one that I've ever played felt like an 80's guitar. yikes!
     
  20. Eagle1

    Eagle1 Member

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    Almost all quality new guitars are compound ,even the Les Paul Std.
     

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