Yamaha headstock / neck break

[Joe Du Toit]

Hello, all!

(Apologies right off the top for no pics, but the guitar in question is not in my possession.)

I have a cousin who owns a Yamaha F-310 (steel-string acoustic) - not a high-end guitar, but it has significant sentimental value to her, and she would be very happy if it could be made playable. Unfortunately, it has a crack which runs parallel to - but not on - the glue joint between neck and headstock. I can see the end of the truss rod peeking out, and it looks to me like the fretboard is the only thing holding it all together.

She had it repaired once before, and I suspect they just injected some glue, clamped it, and called it good. The repair failed, and it separated again on / right next to the same line.

I'm a newbie looking for hands-on experience anywhere I can get it, and I think I'm up to the task of tackling this, but I need some coaching. My instinct is that a simple re-glue is bound to fail again, and that the solution might involve putting in a shorter truss rod, to make room for a piece of hardwood that would fill the end of the truss rod cavity spanning the break. I understand that this would limit the adjustability of the truss rod and thus make perfect neck relief impossible - but like I said, this is a low-end instrument with high sentimental value, and the only goal is to make it playable.

Any ideas on how to approach this would be much appreciated. Thanks so much!

Honest Joe

[Clay Schaeffer]

Hi Joe,
From your description of the damage I would be inclined to separate the peghead section from the fingerboard/neck shaft section, clean any residual glue from the failed repair and then reglue and reassemble the neck as it was originally. Once the fingerboard is "unglued" I'm assuming the peghead can be slipped off the trussrod. I would not modify the truss rod or try to "improve" the joint with dowels or splines. A clean well glued break is as strong as the original construction. Titebond or a similar glue is easy to use and can make a lasting repair.

[Mark Swanson]

Yes, that's what I'd do too.

[Michael Lewis]

And try to keep glue out of the truss rod! The rod MUST be able to move slightly in relation to the wood of the neck.

[Steve Senseney]

You could have your cousin upload the picture--

[Joe Du Toit]

Well, I'll be happy to take the advice not to mess with the design, and simply to re-glue the break. I'm sure you're right, Clay, that the peghead will slip off the end of the trussrod once I separate it from the fretboard. Then I can clean the surfaces and make sure I get the glue everywhere I need it (and nowhere that I don't).

This being my first un-gluing of a fretboard, I'm encouraged that I only need to separate a couple of inches. However, it would still probably be a good idea to get a junker and take a practice run at it, no? Any pointers on the process? (The internet is awash with how-to's on the subject, and I've decided not to trust any that I didn't read here.)

[Clay Schaeffer]

You can try a light bulb or heat lamp placed a moderate distance (+/- 6 inches)above the fretboard to supply enough heat to soften the glue between it and the neck. It may take awhile but don't leave it unattended. once the glue softens you can slip a putty knife into the joint and separate it.

[Rodger Knox]

An old clothes iron can also be used as a heat source. Probably don't need to get a junker to practice, just don't get it too hot.
You do need to get it hot, the glue should release between 140°-160°F depending on what kind of glue it is.

[Joe Du Toit]

Got my hands on some pictures. You can see the light colored wood around the previous break. That repair person appears to have smoothed it over with a clear finish, but didn't attempt to match the color where the dark finish had chipped off. Ideally, I would like to make the break less visible if I could. But again, the goal is to make it playable, so I should probably just focus on structural integrity and leave the color alone. Every scar tells a story, I'm told.

[Rodger Knox]

That doesn't look too bad. Heat the end of the fretboard and get the headstock off first. The nut is probably glued to the end of the fretboard, use a small block on the end of the fretboard and tap it with a hammer. The nut should pop right off.
Unfortunately, it looks like the previous repair was done with PVA glue, it will not be easy to clean it all out and get a really good fit. By the way, getting a really good fit is what will determine the sucess of this repair, the type of glue is not that important. Hot Hide glue would be the best, but Titebond 1 or Titebond Extend as well as epoxy would work. When you've got all the glue cleaned off and it's fitting correctly, figure out you're assembly and clamping procedure, do a dry run, and then glue it. Clamping pressure is also important, figure out how you're going to clamp it without the clamps slipping aroung.

[Clay Schaeffer]

Vinegar can be used to soften PVA as well as many other glues to help in their removal.