That's very bad luck Glenn.

How far away is it from where it enters the head fiiting?

30mm isn't enough to get a fantastic bond, but does the head come off?
If it does it may be possible, a 100mm or so may be enough.
It means tapering off the carbon over that distance, and building it back up.
Hard to do, especially round a curve, if the taper isn't even it will be weak.
A lot of work, and I'm not sure I'd want to trust it anyway.

I converted a 2 arm carbon boom, that used an alli head, into a single piece carbon.
(The alli head corroded due to electrolysis).

This was easy as I didn't have to taper the arms as I had a large dia head, and could just create the new center part over the top of the original arms.

I took it easy with it at first, not going too far out, but after 18 months or so it's still in one piece, (fingers crossed)!

Thanks guys, at least now I know its possible .....

Bludga said he has repaired one before successfully, ended up building the arm up bigger then the original for extra strength.

Decrepit, not sure if the head comes off, its a KA carbon, I hav'nt had a close look at the head. I dont want to fix it myself, just hav'nt got the time, gear or work arae at the mo.

Thanks Fitz, I think I'll get Pete to look at it and decide from there, but I think I'll get another boom anyway