Characteristic
The Zone File is a unique tool that allows you to check the fret level while the strings are on, if necessary, make adjustments with a diamond fi le as it is.
The name “Zone File” is derived from its unique “Z” shape and its meaning of checking and adjusting a specifi c “zone” of three adjacent frets.
To cover the zone from the low fret to the high fret, four lengths were needed. For this reason, the Zone fi les were designed in a trapezoidal shape, and two fi les make one set. (Pat. Pend.)
This “Z” shape has a meaning. The edge of the “Z” is used as a straight edge gauge to check fret rattling, and the diamond fi le in the center of the “Z” fl at surface is to adjust the rattling.
How to use
Try to find an edge perfectly spanning 3 frets
Viewing it sideway, see if the edge you picked nicely touches 3 adjacent frets.
In short, only three protrusions of frets should evenly be situated lengthwise.
You can check the fret level while strings are on!
Set the Zone fi le so that it passes under the strings to be checked.
Select a zone fi le that is long enough to span the three frets to be checked.
Tilt the zone fi le so that its edges touch the three frets, and check with both hands to see if there is any rattling.
If there is no rattling, move the fi le by one fret and continue the check in the same manner.
You can adjust the fret level while strings are on!
If there is any sagging, it means that the center fret is high.
So set the Zone fi le so that the diamond fi le surface touches the fret, and gradually polish to adjust it.
While doing this, check as in step 1) to see if the fret level is even.
If necessary, remove the strings and shape the crown with a crown file.
