Workshop: Plywood Gibson Neck Block Repair

I originally posted this over on my Instagram feed, but it's probably useful to archive it here as well. I don't think this problem has been addressed anywhere else on the net -- at least that I can find.

So what we have here (seen above) is a Gibson hollowbody neck joint from the'50s that’s been stressed to breaking. Not only are the dovetail "wings" broken but the neckblock itself is broken, too, and will not hold the dovetail effectively.

The problem with many of these joints is that the factory used plywood for the neckblock aligned in layers 90 degrees to the string path. This means that if the joint receives trauma (say, it gets whacked or takes a drop on stage) the neck block itself often pulls apart on the ply layers as seen in this case.

Here’s a step-by-step in how I secure these… though purists might find it frightening. If you're triggered by ghastly guitar repairs, please look away.

Here I’ve marked the ply direction of the neckblock with lines of red pencil as the ply layers are hard to see.

Here I’m lightly prying the joint to force the broken ply open so you can see...

…how it’s the ply layer behind the dovetail joint that’s come apart and that whole side of the neckblock where it should be holding the dovetail is "free roaming."

Here I’m predrilling and...

...countersinking for where the screwheads will be.

Here I’m wicking Titebond into the separated ply layer. It's not in the picture but I use a soft brush to wick it into the separated section.

Now the drywall screws are in and I’ve cleaned up the glue mess after it squeezed out in compression.

After this I can repair the dovetail and reset the neck however I like.