The Saga of the Decapitated DiMauro

constantine

I used liquid nails on a similar break and its held up for years.

Bones

Rectangular CF rod(s) laid in a groove perpendicular to the fingerboard with epoxy would be my guess??? but prob need to take off the fingerboard and headstock veneer to do that one. Fairly major surgery...

AndrewUlle

I think he'll do it like this, either with mahogany or carbon fiber stock:<a href="https://ibb.co/jWD9wG"><img src="https://preview.ibb.co/mw6jVb/splines.jpg&quot; alt="splines" border="0"></a><br /><a target='_blank' href='https://imgbb.com/'>gif pictures site</a><br />

Jazzaferri

Go with CF. much stronger

ChrisMartin

A dense wood, maybe a good tight grain mahogany, for the splines and Titebond should do it; many guitars have been made with scarf joints or like the Selmer joint and they have held up.
Carbon fibre has the strength only if used correctly. The fibres need to be going in the right direction and a normal weave used in pieces small enough to fit this job may not be enough. You will need a supplier who uses UD - or uni-directional - fibres to make rods or strips. This way they all go in tha same direction for maximum strength. If this was done correctly up to 1/4? thick it would be indestructible. Also, forget any wood glues, carbon fibre will only bond with epoxies and even that will have to be mixed exactly to specs and everything cleaned thoroughly with acetone. That would be bomb-proof.

AndrewUlle

OK - I'll pick up the DiMauro today - here are some images from the luthier:

Buco

Man that guys is great!
Sweet news.

jonpowl

@Andrew Ulle Just wondering if the splines were used on the sides, too? Why did you go with the narrow part on the crack, instead of beefing it up there? Best of luck! If this doesn't work, will you consider have the neck replaced?

AndrewUlle

The thinking behind the bow tie spline is that the wedge shape will prevent the crack from opening, beyond just the strength of the glue, the physical properties of the shape of the spline. A straight rectangular spline would depend on the glue for much of its strength.

ChrisMartin

Looks like a good piece of mahogany with a tight grain and that 'bow tie' idea is very clever. I reckon that should hold. Did he re-glue the carbon rods inside too?