I've replaced a fretboard on a 1927 00-21, fret slots are cut and ready for fret wire. Looks like Martin, back in 1927, hammered some notches into the fret wire to hold the fret wire in the slot. I'm wondering is that necessary? I see Frank Ford doesn't mention anything about hammering notches into new fret wire before installing, on his bar fret installation. Also what do you use to make the barbs? I have used a hammer and chisel in the past when I just replaced a few frets, but maybe you have another technique.
Thanks Greg, that is helpful.