Fret sloting oopsie
I am afraid that you have to ditch the fretboard and start again. 1mm out will be easily detectable and given how much work the rest of the guitar is going to take it would be crazy to carry on with a faulty fretboard for the sake of £20. Write this one off to experience and just consider it lucky that you realised to mistake before you got much further on. You will thank yourself in the end. Good luck with the rest of the build.
Yes its off by 1mm. I measured with a little $9 angle-izer.
Don’t throw out this one though, keep it for future use. By that, I mean you can find other uses for it such as making inlay fret markers with a contrasting wood. I never throw anything away, it’s very useful and less wasteful to build up a collection of materials and it will save you money in the future.
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