Stewmac String Action Gauge is a "Swiss Army Ruler" for setup adjustments on any stringed instrument. This pocket-size stainless steel rule has become a luthier's favorite in busy shops. It's the best way yet to get vital measurements on acoustic and electric instruments.
• String height
• Bridge saddle height
• Saddle slot depth
• Fret slot depth (unbound fingerboards)
• Nut height
• Pickup polepiece height
Measure string action (the height of the string above the fret) at any point by placing the gauge behind the string. The string height markings are at increments of .25mm (1/4mm). When the bottom of a mark aligns with the bottom of the string, that measurement is the string height at that point.
The markings themselves are .1mm thick, so referring to the top of a mark instead of the bottom adds .1mm to the measurement. In this way the progressive string height scale measures in .1mm increments.
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