Nut

Quite a while ago, I noticed a bit of a buzz in my main classical guitar, the Esteve 1GR-11. I was quite convinced it was in the body, some wire or something from the pickup. It was very mild, on the D string, and only when I plucked really hard. I occasionally shook it, wiggled wires around when I changed strings, but it was not getting better, in fact it was slowly getting worse!

Test strip of paper and new nut
- will need some filing

When I recorded my most recent song, it was kinda bad, and was also now on the A string. So I really took to it properly this time, torch and mirror in the body and all.  I just couldn't see it.  In desperation I asked my wife - "where do you think this buzz is coming from? She immediately said "it's on the fretboard."

Yer what? No way! But, she was right. And to prove it to myself, I slipped a small square of paper, folded onto itself once, under the string on the nut.  And, with the few thou of extra distance to the fretboard, buzz went away.

It makes sense! The guitar was set up from the factory with nice low action at the nut and the saddle. But after years of tuning, dragging the rough wound string through the nut slot, of course it was going to wear material away.

No problem.  I ordered a bunch of bone nuts, you can get them from AliExpress pre-cut to almost the right size. And in they came. Now I just have to sit down with some sandpaper and a flat edge and slowly file it into place...