A break like that is very unusual, and can probably be attributed to wood that has been weakened by decay during seasoning. The name for this is incipient decay, and the impact strength is most affected.
My approach on that one would be to glue it back together (probably with epoxy), just to maintain alignment during subsequent operations. A butt joint is not very strong, which is why the suggestions of reinforcement are appropriate. My favorite reinforcement is a backstrap, whch involves laminating a bent piece of wood on the back of the neck. The neck is thinned in the area (which often includes the whole back of the peghead and down the neck shaft a couple of inches), and then the bent piece is glued on. Finally, the neck is shaped to the original contour. The bent wood is much stronger than the original neck, since there is much less grain runout.
An alternative (which I have done on a couple of occasions) is to glue in a much thicker piece, with the thickest area at the break. This piece is not bent, but carved so that the grain direction is between the neck shaft and the peghead angle. The 'scoop' that is cut into the back of the neck to accept this piece can be done with a 3" diameter drum sander mounted in a drill press. The added piece is cut to fit this 'scoop' using chalk fitting techniques.
|