Discussion in 'Luthier's Corner' started by Threeviews, Jun 22, 2005.

  1. I had a gorgeous, very hard and resonant board of Jatoba that I'd been scheming about for some time now. It was too thin to make a body or wings out of, but just to cut a neck or two from it seemed a waste. And I'd been thinking a lot about design acoustics. If we lose vibration with every joint and material change, what would the possibilities be for an instrument on which both string ends (or both bridge and nut, I guess) were anchored to the same piece of wood?

    So now I've cut a 34"-scale unibody slab and sized it for a fretless curly purpleheart fingerboard. The body design had to compensate for the width of the original board, which didn't allow for the width I usually prefer across the body. ("big through the hips"?) But I've come up with what I think is an attractive instrument just the same. My concerns are:

    1) that the flat neck/headstock transition may not be as stable as a scarf or tilt-back volute. There will also not be the kind of downforce across the nut that I'd need...unless I mounted the tuning machines to the front of the headstock and ran the strings through to the other side, which might weaken the headstock/neck joint anyway? (and wouldn't that look weird?)

    2) that, although the neck is awesome, the body is now very thin (Could I just veneer the front and back? Would this counteract the unibody idea?)

    and 3) for that matter, whether I need a fretboard at all (if I can rout the truss from the rear, skunk-stripe-style...)? I realize this would mean massively 'countersunk' pickups...not to mention a bass that looked like the back of a puzzle piece...

    Anyway, I have no idea about the feasibility of any of these ideas and design possibilities...although that hasn't stopped me yet. +) Anyone tried something like this? Any advice?
  2. Keith Guitars

    Keith Guitars Supporting Member

    Aug 25, 2004
    Woodstock, NY
    Builder: Martin Keith Guitars, Veillette Guitars
    This has been done - in fact, there is a patent on file for what someone was calling "Unitary guitar construction", under which the entire instrument (less the fingerboard) was cut from a plank of mahogany.

    The headstock/neck joint will be slightly less strong, since the headstock grain will be running out - however, many acoustics are built like this, with no apparent issues. Collings is still doing this on many production guitars.

    Other than that, I can't think of any major *structural* issues... However, there are standard design elements which will be missing, and which may compromise the comfort level of the finished instrument:

    -The "feel" of an instrument whose fingerboard was that close to the surface of the top would be somewhat strange - there would be next to no string clearance over the body. The bridge would also need to be seriously recessed as well.

    -Almost all guitars/basses have some degree of neck back-angle (that is, the fingerboard plane is not parallel to the top). An instrument without neck angle sometimes feels a little bizarre. Rickenbacker 400x basses are close to zero-angle, and have very thin bodies, but the fingerboard is elevated off the body face to compensate.

    I would modestly suggest that if the piece is long enough, you should cut some neck-through blanks from it. These will give you the structural integrity of the single piece idea, while letting you make more efficient use of some nice wood.

    Best of luck,
  3. If you're looking to "keep the vibratrions" neck-through is a waste of time. Set-Neck is the way to go, ZON seems to think so. They explain pretty in detail on their website about why they use set necks instead of meck through or bolt on.