Ugggggghhhhhhhh (help?)

Discussion in 'Hardware, Setup & Repair [BG]' started by Indi86, Dec 5, 2005.

  1. I'm worried that my fretless Acacia 4 may be developing a crack at the base of the neck. The neck is 3 pieces,with 2 stringers and a line is there running on a curve from perpendicular at the treble side to parallel to the grain on the bass side. The whole line, which can be felt very slightly to the touch for about a 3rd of the way, runs about 1.5 inches. The whole thing takes place within 2 inches of the bolt-on joint.

    I don't know if the wood has just dried out a bit (i didn't get to play it for 3 months and it sat in its THICKLY padded gigbag in an abnormally dry fall) or if it's some sort of stress crack that's only taking place in the center laminate. The centerpiece is either walnut or bubinga... i think. The outside pieces are both wenge.

    If I can, I'll get a pic, but I'll have to borrow a camera.
     
  2. Here we go.

    [​IMG]

    [​IMG]
     
  3. I have a small 30x pocket microscope that comes in handy for looking at stuff like this and getting to the nitty gritty. You can read the serial numbers on the molecules with it! That's the only way to tell for sure. but I'll tell you some things that bother me - Those woods are naturally finished so there's little chance of that being a crack in the clearcoat. Second, what I know of those woods from handling them, they can be made to crack easily. Your mention of dry conditions would verify this. But the one good thing is that it's unusual to have a crack run across such straight grain unless there's some whopping impact applied - does breaking a baseball bat ring a bell? Maybe take some naptha and wet it and see what it does. Beyond that, you've got me at a disadvantage ;)
     
  4. Oy. What am I looking for/ what's your shipping address...

    In any case, i certainly haven't been using it as a weapon or dropping things on it.
     
  5. jeffhigh

    jeffhigh

    May 16, 2005
    To me it looks like there may have been some impact. It is common to see this sort of crack in a acoustic guitar heel block, parallel to the fretboard.
    I am not familiar with acacia, but it looks from your pictures that there is one single screw, centrally mounted near the crack.
    most bolt on situations use two screws away from the centreline,with the scew extending deep into the neck, almost to the fingerboard
    perhaps this central screw cannot go deep because of conflict with the truss rod, and the neck has split at this level.
    Anyhow, it will probably need a good glue and clamp job, preferably with the glue injected under pressure, probably from a hole drilled on the mounting face.
    Jeff
     
  6. It's a 5 bolt neck. The bolt in the pic is going through the bass-side wenge.
    There is another one 3 inches farther down the body running inline with that one.

    There is a center bolt about 1.5" back and running dead center into the middle runner. For scale it's about 2 inches from the base of the crack.

    The last 2 bolts are about .45 inches apart on the treble-side wenge, another .3-.4 inches back from the center bolt and running dead center through the treble-wenge.

    The truss rod is accessed at the headstock.
     
  7. A front shot for slightly more reference. I won't be able to get a larger area shot of the heel until tomorrow evening. [​IMG]
     
  8. OK: looks live I've got to head to the NYC to get 'er fixed. Do you guys recommend Rudy's?
     
  9. basstruck

    basstruck Guest

    Nov 25, 2005
    Sudbury
    Remove the neck, fill the crack with "super glue" strickly "super glue" nothing else until it over filled, wait 1 hour to let it penetrate and fill it again. Cover your fingerboard with a piece of wood or something to protect it same with the back of your neck and clamp it if you have any kind of clamps and let it dry for 24 to 36 hours. When it is dry, gently sand down the dry glue with 320 sand paper and finish it with 1200 wet sand paper and finally buff it with car wax and put back the neck on the body.
    It will never move again if it breaks it will break somewhere else. If you don't trust me, just take it to a "Luthier". That's probably what he is going to do to fix it.