Fret levelling

Grinding or filing the tops of the frets down to a common plane so that no single fret sits higher than its neighbours.

A long flat file or beam is drawn along the neck until every fret shows a fresh mark, after which the flattened crowns are re-crowned and polished. It restores buzz-free performance on a well-used instrument, and it is the standard remedy for a hump at the neck joint or a high fret. It removes metal, so frets can be levelled only so many times before they need replacing, and a full level means the crowns must be rounded again or the notes will sound thin.

Example: a guitar refretted with a levelled and crowned board can be set up with very low action because every fret is on the same plane.

Fret levelling

See also