I may have over engineered it

I have a bunch of carbon fiber fabric and epoxy resin from other projects. So I turned a dowel the correct diameter and waxed it and then wrapped it with carbon fabric and resin to make a carbon tube. I cut that tube into four sleeves. I planned to glue them into the headstock, but I was experimenting so I just pushed them in (tight fit) and that was two years ago - they are still working fine so I may never glue them in.
If I were doing it again, I'd probably take scissors (not your wife's "good scissors") and cut a beer can into strips and wrap the aluminum strips around a dowel. Much easier and faster.
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