Mustang Bass Fingerboard shrinkage?

[Bob Hensley]

Fellow just brought in a Mustang bass to see if we can put it back into playing condition. Main problem is the fingerboard - it is loose most of the length of the neck, but that isn't the problem - it is narrower than the neck!

It is almost like there is binding missing - there is a sharp ledge on each side of the neck from end to end, but no indication it ever had any binding. I first thought some sort of shrinkage, but the fret ends aren't sticking out from the edges of the fingerboard. And it is less pronounced at the end where it meets the body, but still about 2/64th from fingerboard to edge of neck on each side. Max seems to be around 3/64ths around the middle of the neck.

Has this fingerboard been replaced at some point? Can a fingerboard shrink without frets sticking out? And what is my best bet  to get him playing again?

Pics attached.

[Paul Verticchio]

Hi Bob.

My first impression, based upon your photos, is that the neck has either been submerged in liquid or has been in an extremely humid environment for an extended period of time. It's definitely been neglected.

Have you tried drying the neck with heat? The maple may return to its original profile.

Alternately, once proper wood humidity levels are reached and if the neck is still to wide, the neck can be re-profiled to match the width of the FB.

One of the main draws of the Mustang Bass is its narrow neck. They're at a maximum desirability point as of this writing only to younger musicians and especially female bassists. They're cool, but are barely a cut above a bare bones utility instrument.

I imagine that in all cases, you'll need to remove the FB & re-establish a proper glue joint the neck. Since it's a thin veneered board, good luck with that.

Best of luck with the project and we'd love to see photos of it post repair.

Kind regards,

Paul

[Joshua Levin-Epstein]

(To state the obvious) This neck was fretted from the side. In my distant youth I saw a video from the factory showing this process and the final shaping of the fingerboard (the bevel) was done the same time the fret ends were cut off.

I initially thought there might have been a mis adjustment of those shapers resulting in a skinnier fingerboard. But that would have left finish on the gluing surface of the neck.

Have you tried clamping the fingerboard? I am thinking that once the glue joint failed,  the fingerboard cupped, leaving the gaps you see. If the fingerboard covers the gaps when clamped, I would be tempted to treat this like the Martin Pick guard that has shrunk but is still attached in places.

http://www.frets.com/FretsPages/Luthier/Technique/Guitar/Pickguards...

You might be able to avoid a complete refret, though a leveling will be in order (just like it was when the guitar left the factory).

More of the obvious:

If it needs to be refretted, drive the frets out from the bass side of the neck. Check Dan Erlewines book for techniques. This might be made easier by the fingerboard being loose, but ...

The fingerboard is not veneer per se. The underside is carved to match the radius of the top of the neck