Neck bowing in an odd place

[Daniel Nestlerode]

Hello all,

I thought I might ask for a little advice about a bowing neck.

I have a Fender FM-988, 8 string electric mandolin whose tone I love, but whose neck is annoying me.

The extra long headstock seems to create a problem for the truss rod. The stress on the neck occurs closer to the nut than on necks with more reasonably sized headstocks --or back angled ones for that matter.

The headstock is pitching forward and the dip in the neck seems to occur around the 4th fret.

Has anyone tackled this type of issue?
I suppose I could plane the fingerboard, but I'm not sure that would be a good long terms solution. I wonder if taking material out there would weaken the very spot that is flexing, and make it worse.

I'll post photos as soon as I can get them to load.

Thanks!
Daniel

[pops1]

Is the truss rod broken or very loose?? Only thing I can think of before more coffee.

[Daniel Nestlerode]

Thanks Pops!
But the truss rod is snug.

Daniel
Yay! Photos!

[pops1]

Daniel, if you measure with your straight edge along the neck, where it meets the fingerboard is it straight or curved? Looks like you may have to plane it to correct it. I have mandolins with very small necks, and the truss rod keeps them straight. I think it was made this way. I would plane it.

You could also loosen the fingerboard from the neck about half way from the nut back. Clamp the neck so it is straight, or slightly back bowed, and reglue the fingerboard. I have done this with warped necks with success.

[Dale Ludewig]

I don't think the headstock is pitching forward. That's how it's machined, isn't it?

[EdHanrahan]

Just one non-professsional's observation:

If there really is a "dip in the neck ... around the 4th fret", that's not obvious to me in the photos. It would be interesting to measure a string's clearance over each fret to determine if the fretboard really does have areas of inconsistent clearance/releif. I'm not saying such a dip is NOT there, just that it's probably minimal in comparison to the headstock's obvious forward pitch (as viewed in comparison to the ruler held against the top of the body), and maybe not the source of such forward pitch.

From what I see in the photos, most of the issue seems to be at the base of the headstock itself, being just outside of the trussrod's reach; most likely warped wood that started from the original neck blank. Since the metal string retainer ensures that the strings are well-angled over the nut, it seems possible that the headstock's angle is mostly a cosmetic issue, and maybe obvious only to those doing measurements.

If this guesswork is accurate, the good news is that the fretboard s/b fairly straight & playable, and well-controlled by the trussrod.

FWIW, my interest is because I have a Fender P-Bass Lyte that plays well & responds to trussrod adjustments, but does have a shallow "V" of releif right at the 17th fret, where the neck transitions to rectangular at the bolt-on pocket. The dip is not obvious unless you look for it (preferably w/ a straightedge) and the guitar plays so well that I've not been moved to correct it.

[Richard500]

Daniel, i think your analysis is valid w/r/t the angle of the headstock. That it’s a design feature is shown by the staple that holds the strings down, but does little about the torque that’s raising it. Torque that would try to bend the neck. Wouldn’t worry about the length beyond the tuners, as the stress is applied below that.
No suggestion about remediation or whether you’re at a limit or it’s still progressing.
Strikes me as odd that a solid body electric, with none of the delicate architecture of an acoustic instrument, would have such a designed-in weakness as that headstock.

[Daniel Nestlerode]

Thanks all.

To be honest, I had not thought that a forward angled headstock would be a design feature. That staple has always driven me nuts. I don't think I have changed the strings more than 3 times since buying the thing in 2007 or 2008.

The bowing seems to be stable. It has always felt the same to play, and more recently, with the purchase of higher quality instruments, I have realized why I haven't been able to play as quickly and articulately on that mandolin as my others.

I'll take it to my local luthier and see what he says. We will probably try planing the fretboard. And if that doesn't work --or works only for a short while-- I'll look into a replacement neck.

Thanks again everyone for your input!
Daniel