A guitar fret can be described as a "crown" which is the visible part over the fretboard and another part which is
sunken inside the fretboard.
Guitar fretwire can purchased pre-cut or in rolls and although referred as German silver or made in "nickel/silver",
actually contains no silver at all and it is manufactured from brass and a very small percentage of nickel which gives that silver colour.
Frets must be glued into the slots using aliphatic resin (Titebond glue) or epoxy glue to allow them to stay firm in place.
Gluing the frets also allows to fill the empty spaces remaining between the frets and the slot and to diffuse vibration more evenly. through the neck.
The fret slots should cut to perfectly to guest the frets both in width and depth so not to weaken the neck and compromise stability. If fret slots are too narrow, hammering the frets in will result in a backbowed neck which the strings tension and the truss rod may not be able to counteract.
The way the fret is installed into the fretboard has an importance not only in the tone but also on the comfort and performance of the instrument. Frets installed in the slots which are too deep or where glue has not been used to fix them, a fret radius that doesn't fit the fretboard, radius, frets that don't lay evenly on the fretboard, all this has a negative influence on the tone and creates frequency holes and poor string vibration.
COMFORT AND PERFORMANCE
After frets are installed they must be dressed, rounded and polished by hand to ensure the maximum playing comfort and intonation. HINTS AND TIPS
Before installing the frets remember to clean the fretwire with acetone or thinner to remove the grease applied during the manufacturing which would prevent the frets to stay in place once installed into the slots.