Ovation Guitar Neck Reset Continues

On the right we have my calculations for the amount of material to remove from the neck heel to reset the neck.

This is basically geometry I think.  What we need are the distance from the center of the saddle to the edge of the body (marked "A"), the height of the neck heel (marked "B"), and the difference that the straightedge placed on the frets contacts lies below the top edge of the bridge.

Note that the "B" distance is the height of the heel, not the body.

Then we take those numbers and solve for "X" in our formula - which is the amount of material needed to be taken off.  It's easy to calculate - the difference times "B" and that sum divided by "A."  In my case I got about .020 of an inch.  That's the amount to be taken off the bottom, tapering up to nothing at the top of the heel where it meets the body.

Hopefully you can visualize how this will tilt the neck back and make the plane of the fingerboard lie where it should.

I marked the neck heel with blue tape to get a guide of how much material to remove.  Again, there is about .020 at the bottom, and that tapers up to zero at the top.

What you need for this operation are really good, sharp chisels.  My chisels are mediocre quality, so I sharpen them up and proceed carefully.

I also have a good set of small scrapers that come in handy.

Between my so-so chisels, the scrapers, and sandpaper used judiciously, I'm able to remove the wood to make the neck set correct.

The Ovation neck joint is different than a more traditional joint on, say, a Martin.

In addition to the heel itself, I wound up shaving some material off the block that carries the threaded inserts for the neck bolts so it would sit properly in the slot on the body.

In practice, I take some material off, then check the neck on the guitar.

After some endless back and forth, the set is corrected.  The straightedge now just touches the top of the bridge.

Then I take some 120 grit sandpaper, put it between the heel and the body, and pull it downward (toward the back) to get a tighter fit to the body.

In the process of cutting the neck, I have some chips that came off the heel.  Sometimes they do, sometimes they don't.  So I need to fill and finish the chips before I can put the neck back on.