Universal Notched Straight Edge | GMC Luthier Tools

The Guitar Notched Straight Edge accurately checks the neck straightness & fretboard flatness independent of the frets.


The original design ensures that multiple scales are catered for with a single tool.



A removable steady prevents the tool from toppling over, allowing it to remain safely positioned on the neck during setup and adjustments. (The steady can be used with or without strings fitted).



The design of the tool is based on checking the length of the fretboard that is capable of being deflected. The very highest frets are omitted since these are well beyond the heel/neck join and won't be affected by truss rod adjustment or string tension.


The tool has 18 notches and a double dot mark for position reference is provided. The positioning on the neck will vary depending on the scale of the instrument:


The dots are nominally positioned at the 12th fret.

For shorter scales, the dots are placed at the 11th fret and for longer scales the dots are placed at the 13th fret.

There are 4-versions of universal notched straight edge available from the webstore:

24" to  27" Guitar Scale - With Precision Straight Edge

24" to  30" Guitar- Baritone

27" to  34" Baritone - Bass

30" to  38" Bass



  • Multiple guitar scales accommodated.

  • Freestanding use (with steady) and conventional use.