Diagnosing buzz after level/recrown

@DuckBaloo I did the same. When I was using way too much pressure on the file, I wasn't left with a very neat line across the whole length of the fret, which turns out was very much an indication that something had gone wrong.

When I just let the weight of the tool do the work, I was left with a much cleaner line across whole length of the fret and got much better results.

I had practiced this on a beater Squier neck first, but that neck didn't fit neatly onto this guitar, so I wasn't able to easily test drive the result on an assembled guitar before I gave it a go on my actual neck.

As you say, all a learning process. I've got a dream build of mine on order, and feeling a lot more confident to do whatever work is required on that project once I get it.