Sonus bass with bowed CF neck fix?

[Kingfish]

Howdy all,

I got a ZON Sonus S4 fretless from a friend, but there's a bow in the neck and the company told me it's $875 to rebuild the neck. Yikes. The bass plays ok, but the action at the 9th fret is 1/4". Can a luthier straighten out the neck with heat and pressure?

 

[winegamd]

What year is the bass. Newer Sonus necks have truss rods. Is the action from the neck relief or the bridge? What bridge is on the bass? Do you have any pictures of the problem?

 

[Kingfish]

1994 - this one doesn't have a truss rod. It's the neck relief that's raised the action; ZON told me the fingerboard "relaxed" which allowed the bowing and that rebuilding the neck is cheaper than replacement. (It's got a ZON bridge on it). I can try posting a photo this wknd. The bass is playable but I intend to sell it eventually and wouldn't get much in its current condition.

 

[winegamd]

Moses offers a replacement neck that may be a bit cheaper, but still >$600. You might try using light gauge strings. That might lower it some.

 

[Kingfish]

Thanks. I got in touch with Moses Graphite. They have a neck for $425.

 

[Bob_Ross]

fwiw I have a Modulus Graphite bass that exhibited the same issue several years ago...and yes, the neck had to be completely rebuilt. I sent it back to the factory (this is before Modulus went OOB) where they removed the fingerboard, then shaved down the top surface of the neck (that the fingerboard is attached to) until it was flat again relative to a taught string. Then they added some internal reinforcements to -- hopefully -- prevent this sort of thing from ever happening again, and re-attached the fingerboard. Not a job for the faint of heart. Probably not a job for a luthier who isn't very experienced with carbon fiber repairs either.

 

[SLivinghouse]

There a few folks on here that have done CF builds (MPU for example) and his advice would be better than mine. I do know that resin does soften with heat but what temperature would be needed is a function of the type of resin used and there are many types. Some also give off nasty gasses. You might also want to learn more about CF and laminates if you want to try it yourself. If you are going to toss the neck, you mind as well try to fix it right? Boating and surf board building sites have a lot of info on laminating.

 

[Zooberwerx]

Jerry Dorsch / Graphite Guitar Systems...google it for full details. Rescuing graphite composite instruments is his stock in trade.

Riis

 

[jdthebassman]

no truss rod no deal. I would sell that asap