Neck Fit

This usually requires expanding the neck to fit snuggly in the tenon but can also require shrinking the tenon. Ultimately the goal is a perfect mechanical fit which require dent tools that expands the tenon in all directions and fine lapping compound to abrade the high spots to the point that they meet the low spots. The point of all of this is to remove one of the earliest possible points of leakage that are not always considered with horns that are not playing well.