A full set up consists of adjustments to the following

Although a basic set up will tame the worst excesses of a default factory set up, for many guitars, even new ones, this will not be enough.

In order for the guitar to be comfortable to play, deliver the lowest action and the most accurate intonation it's important that the neck is as straight as possible.

Under ideal conditions the neck will actually have a very shallow curve in it, controlled by the truss rod, but for practical purposes this should be almost negligible; most manufacturers publish a figure of approximately 0.01" for the value of the arc relief measured at the midpoint of the neck. Over a span of two or three frets however this equates to a drop of only around 15 microns. This is considerably less than the diameter of a human hair; in fact it is a quarter of the diameter of the wire gauge used in pickup coils.

With the neck correctly adjusted, if the frets are out of alignment by significantly more than 15 microns, a buzz may result.

There are, of course many other sources of fret buzz, some of which are not in the technician's power to eliminate as they may stem from the player's technique or demands for ever lower action height, however the process of fret levelling and dressing is an important procedure in eliminating this as a possible source of fret buzz, allowing the technician to optimise the action height.

Although fret dressing can be used to cure minor fret wear, it is not recommended for heavy fret wear where a refret may be mandated.

The actual process involves careful mapping of the high spots on the fingerboard and spot filing of the fret crowns, followed by careful re-crowning of the frets to a round profile for accurate intonation and a comfortable feel to the frets.

Occasionally sprung frets may need to be removed and re-seated.