Finishing up the frets on Mike's Wal neck.....
The first step is to gently drag a Sharpie across the tops of all of the frets. It makes a dark blue line across the crown, and makes it easier to see where the crowns are being ground during the leveling.
Leveling the frets. I use this special custom tool, an aluminum bar with six 320 grit grinding stones attached to the bottom edge. I wrote a thread over on Luthier's Corner about how to make and use these. I'm gently sliding the bar over the frets lengthwise along the neck, following the string paths and fanning in between. It's very important to follow the string paths, angling the bar to match the string spacing taper.
I grind the tops of the frets just enough that I can see that every fret is being touched by the stones. I'm looking for a thin shiny line in the middle of that black Sharpie line, on every fret. That's what fret leveling is all about, making all the frets exactly the same height.
By the way, the fret leveling is done with the truss rod tightened to about 40%.
After the frets look like they are leveled, I go over them with a Norton Medium Oilstone, in gentle strokes along the length of the neck. This takes the grinding scratches on the frets up from 320 grit to about 800 grit.
You can't see it too well in this picture, but the frets all have narrow shiny flat lines along the tops of them. The widths of the flat lines vary with how high or low the fret was in relation to the others. I carefully check them all to make sure every one has been leveled, all the way across.
Then I use the Norton oilstone again, sliding it lightly across the width of the neck. This turns the 800 grit grinding scratches along the line of the frets, so you can barely see them.
Crowning the frets: I go over each fret with a
Stew-Mac Crowning File, on the narrow size edge. A crowning file has a small concave groove shape. Sliding it over the fret grinds the sides of the curved crown, making that little flat surface on the top narrower. The goal is to make all the little shiny flat lines very narrow and equal.
Polishing the frets: I use a Dremel-type tool with a rubberized abrasive fret polishing disk. On stainless frets, I only use the Very Fine disk, which leaves the frets at a semi-shine. Going over them again with an Ultra Fine disk will take them up to looking almost like chrome. I personally don't like the frets to be that shiny on most instruments.
The fingerboard is protected by a stainless guard plate, held down by two strips of black electrical tape. I polish the frets one at a time, lifting and moving the guard down the neck.
Then wipe off the grinding dust and the Sharpie residue, and pass the fingerboard over the ebony buffing wheel one more time.
I reinstalled the tuners and the brass nut. A quick check in the nut slot heights, using a thin 6" machinist's rule. With it resting in the slot and on the 3rd fret, I'm looking for a small gap of 0.003"-0.005" at the 1st fret. The nut appeared to be fine in relation to the new frets. I didn't need to do any filing of the slots. The nut is glued down with two drops of CA glue.
And it's done! Ready to go back in service. Mike contacted me and he was in a town nearby for the week. So he drove down and picked it up in person today. We chatted about Wals and I showed him around the Lab.
For your reference, the total bill was $240. It was about 5 hours' work, not a difficult job at all. Any competent Luthier should be able to do what I did here on this neck.
Coming up: Finishing up the fretwork on Alex's Wal neck. Same things I just did on Mike's neck.
