I agree with Mike - maybe a roasted bird's eye maple ---ohhhh...ahhhhhh. Beauty Wal - sorry to hear of the truss rod.
Non sarcastic question- How does this happen to a truss rod? Flaw in the metal? Too aggressive of adjustments? I hear about this from time to time - just like to dodge the bullet ahead of time if possible. Thanks
Roasted birdseye definitely has an appeal!
And I wish I had an answer to your truss question as well!
Here's some more to it:
When I got the bass, the action was too high and the neck had some bow. The truss felt like it was tightened as much as it wanted to and I certainly didn't intend to force it. It stayed like that for years until I was able to get the bass looked at by a great local repair guy.
After he diagnosed a twist in the neck and planed the board down to a flatter radius he had essentially done all he could with what was there. It was actually in a pretty good place action wise. There was an area around the 12th-15th fret that was buzzing a bit and the only real solution was to replace the board. So I was planning on that anyway.
Now that the weather has changed and we all enjoy the fun of adjusting our instruments the action - which again, was fine when I got it back - was now a little high and the neck needed to be adjusted. I was able to adjust the truss to a point where... it just didn't want to go any further. I could still turn the nut slightly but it felt like it moved back a bit. And there was no difference to the neck.
I backed the truss off the other way to comically high levels then tightened again and got to the same spot. Just not where I need it and in no danger of introducing a backbow if I wanted it. I tried to finesse it a little further and I heard a sharp crack. Having never broken a truss before I honestly didn't know that I had. I thought I had cracked something in the wood somewhere.
But what I saw was that now the strings were about a half inch off the neck where a moment ago they were half that. So that seemed like that.
To sum up, I think there was an issue with the truss to begin with and I ended up killing it.

