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Hey gang -
I have a guitar I built last winter that is now giving me (and the still-proud owner) grief, the 5-laminate neck is twisting at the nut end making the treble strings' action rediculously high. I used a StewMac "Hotrod", which I will never use again...they twist end-for-end by nature, I suspect that's what caused my problem.

Now then....how to remedy? I removed the fretboard last night, cleaned up the glueing surface. Sighting down the neck, I can plainly see that the treble side is a good 1/8" taller at the nut than the bass side, but the heel end is totally perfect. I was all set to have to run the whole thing across the jointer and hope for the best, but now I see that it would be much easier to just "untwist" it. With one hand on the headstock/one on the heel, twisting the opposite way , it sure doesn't take much effort to make everything square once again.

This being the case, should I:

1. Apply heat to the neck and clamp to a perfectly flat surface (such as Corian, or maybe the tablesaw)
2. Apply heat and figure out a way to untwist it a little past square, allowing for a little spring-back
3. Twist it straight and glue on the new fretboard, relying on the glue joint to hold the position when it dries?

This whole thing has been a learning experience, and reaffirms my loyalty to LMI trussrods!

Thanks,
Jon

Jon--

What glue did you originally use to glue the fretboard to the neck?

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Jim Howell
Charlotte, NC

Epoxy. After reading how many others prefer this over Titebond (as epoxy doesn't add any moisture), I started using it on this very guitar. I like it, but it sure makes for a difficult removal!

Jon--I doubt that the twisting is caused by the truss rod but rather by stresses in the neck wood trying to relieve.
This could probably be verified by loosening the truss rod and then checking flatness of the neck/fretboard interface.

Thanks for the reply -

The fretboard is off, trussrod removed. The neck itself is definitely twisted.

Jon, I'm afraid Nelson's right about the stress in the neck causing the twist. Also, I'm surprised by the fact you can twist the neck so easily. What's the neck made out of and what is the grain orientation?

Hopefully someone will have a good fix for this problem.... but you probably will have to build a nice new untwistable neck...

long

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"No man ever steps in the same river twice, for it's not the same river and he's not the same man.” -Heraclitus of Ephesus

Jon buddy I agree with Nelson too - stresses in the neck wood and/or unacclimated neck wood built in unstable RH are likely the culprit. The truss rod won't have any thing to do with it and you indicated that with the truss rod removed the neck is still twisted.

It you true up the neck surface, there is a toot for doing this with sand paper on a flat surface, or use a jointer where the headstock angle begins in the nut area is going to not be square. And there is a possibility that this neck is not finished moving either.

I would build a new one too with acclimated materials in an RH controlled environment.

Also, since you mentioned it, what epoxy did you use to glue on the fret board? West Systems releases with low heat and would not have been difficult to remove where other epoxies can require much more heat.

Thanks Bob and Hesh for the direction!

I'll probably just wind up making a new neck. Might mess with this original one a bit, but won't waste too much time on it. Was just wondering if there was an easy cure for the problem.

The woods are mahogany along the outside, then two 1/8" strips of some very dense braz cherry, then maple center. Grains are all relatively longitudinal, running the length of the neck except for the maple center, which has a slight angle (vertical, not left to right) in orientation. All had been in the shop for a couple months prior to the November build, RH in the shop is usually around 48-50%. All in all, it's a thin neck but not too thin. When I say it's easy to bend back, I mean that I didn't have to really horse it...and it doesn't have all that far to go to get back to being flat, which is why I was considering un-twisting vs. trying to shave it down.

The epoxy was nothing special....just the usual Ace Hardware variety.

I untwisted a neck once with heat, similar to a heat set. But this is done with the fingerboard attached, as it relies on the fingerboard joint to be softened and reset, which holds the new set.

Since your fingerboard is removed, you have sort of leap frogged the idea of a heat set. What I would do would be to simply reglue the fretboard with the neck twist over-compensated in the other direction. You would need to come up with a way to hold the neck in this overcompensated position while the fretboard is glued and cured. That is where you have to get creative. Regarding how much overcompensation is appropriate is anybody's guess as each neck would probably be different. On my repair, I went about 1/32" beyond flat as measured at the edge of the fretboard at the nut. When I removed the neck from the clamps, it went back to perfectly straight. I got lucky. Let me know if you want a photo of my setup.