fretless neck with carbon rod only??

[dlmarquez]

Does anyone here build necks with a carbon stiffener bar, but no metal truss rod? This would be sort of like the neck Vigier puts on their rather expensive basses.
I'm extremely intrigued by the concept of a bass with no metal truss rod, I have the suspicion that it would sound different and have different sustain properties.
I'm referring specifically to a fretless unlined neck Probably a P profile, a bit on the chunkier side than a J neck, with a Carbon stiffener bar/rod to provide stiffness.
My question to ya'll is this: has anyone experimented with this idea? Does anyone have experience. I've heard lots of "NAYS" on this subject, mostly relating to the fact that you no longer have the ability to adjust the neck relief. However Vigier seems to be able to make this idea work. I'm very very curious!

[ehque]

My bass neck is one big carbon stiffener bar, and yet it has a truss rod...

I'm sure it could be done, but you'd need a lot more carbon stiffener than 1 bar, or a lot more wooden neck.

[ped]

I have had several Vigier basses with these types of necks and never had a problem (patrice Vigier says he has never had a neck back for adjusting either).

My favourite neck is the 100% carbon neck on my oldest bass because it has zero relief and a super low action which I like. I had a newer series 3 (carbon/wood mix) bass which has a 'textbook' amount of relief built into the neck (credit card thickness) but I prefer none or very little so I sold it on and the current owner loves it to pieces.

The thing is that the carbon rods are extremely dense (75%) in carbon which apparently gives them greater strength than the graphite weave design.

Cheers
ped