String Action Gauge

  • 158 Reviews
  • Write a review

Fast, accurate measurements for setups. Our String Action Gauge is a "Swiss Army Ruler" for setup adjustments on any stringed instrument.

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Item # 0670
In stock, ready to ship!




Item # 0670-M
In stock, ready to ship!


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Quantity: 20


String Action Gauge

Dan Erlewine uses this gauge for checking string height, measuring saddle and pickup heights and more.

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Fast, accurate measurements for setups. Our 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

No more "three-and-a-half-64ths or 3/32" plus one of those little lines." This gauge measures in ways that regular rulers can't. —Dan Erlewine

Developed here at Stewart-MacDonald by Dan Erlewine and Don MacRostie, the gauge features a progressive string height scale: simply slide it across the frets and read the measurement under the string. It's faster to use than any ruler, and stays parallel to the fingerboard—much easier than trying to hold a ruler perpendicular to a rounded fret. The string height markers are graduated from .010" to .140" on the inch model, and from 0.25mm to 3.50mm on the metric version.

The back of the gauge has a time-saving fractional/decimal/metric conversion chart.

The String Action Gauge is made of durable stainless steel with precision-etched markings, and fits right in your pocket.

Tip: You can use the gauge to set router depth, instead of a shop ruler. It sits solidly on your router base, with the scale right where you need it.

Product Instructions

Making a Nut, Step-by-Step

Dan Erlewine, of Stewart-MacDonald's R&D Team, walks you through making and installing a new nut.

Product Instructions

String Action Gauge

How to determine string action with the String Action Gauge.

Product Instructions

Metric String Action Gauge

How to determine string action with the Metric String Action Gauge.

Ratings & Reviews

String Action Gauge

  • Based on 158 Reviews
Displaying 8 of 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Write a review

Nice, but hard to read

By Robmase from Charlotte, NC
(Customer's Reviews) Saturday, May 19, 2012

I use this tool quite frequently, but it should come with a magnifying glass to read it. lol. I find myself tilting the guitar and having to make awkward angles to read it. The guitar pretty much has to be eye level with good lighting.

The first thing I grab for a setup

By Equitz Guitars from Placentia, CA
(Customer's Reviews) Friday, May 18, 2012

Invaluable! Having the 64th measurements from both sides in addition to the graduated string height increments puts this beautiful little tool on a pedestal for me.

String Action Gauge

By Scott Evans from Hobart, Tasmania, Australia
(Customer's Reviews) Wednesday, May 16, 2012

The all-in-one tool for strings, pickups & nut depth. Makes checking of existing hardware or setting up new hardware a breeze!

Perfect tool

By Miguel H Pe+¦a from Venezuela
(Customer's Reviews) Saturday, April 28, 2012

Not much to say but it is a useful tool to calibrate the guitar.

Great idea and execution.

By Demac from Seward, NE
(Customer's Reviews) Wednesday, March 14, 2012

Perfectly sized and marked for every action related measuring task I can think of, and probably quite a few others as well.

Thank you

By Mr.Jittrailert from Thailand
(Customer's Reviews) Monday, March 12, 2012

Standards were very good time,I will support new,send information about new tools to help with.

An Excellent Tool

By M Dawes from South Shields, England
(Customer's Reviews) Saturday, March 10, 2012

This tool assists you in measuring string action height, but it doesn't just stop there you can use it for accurately setting routers or any plunger cutter, it also serves as a miniature ruler, a measurement converter and has numerous uses. It saves you valuable time and it is one of these tools that once you start using it you don't know how you managed without it, a must have tool and very good value for money.

Indispensable para la calibracion y mantencion

By ACHguitars from Santiago, Chile
(Customer's Reviews) Wednesday, March 07, 2012

Esta es realmente una muy buena herramienta para calibrar y hacer mantenciones.
Es de muy facil lectura y sirve para todo lo que se tenga que medir en una guitarra, accion, altura de capsulas, etc.
La recomiendo plenamente


By lgn from belgium
(Customer's Reviews) Wednesday, March 07, 2012

perfect tools

Make it easy on yourself

By Andrew Faltesek from Saint Paul, MN
(Customer's Reviews) Tuesday, February 28, 2012

You can cetainly get by with a precision ruler, Starrett caliper, feeler gauges, etc., but if you're doing more than one setup make it easier on yourself and get this measuring tool. I gently used 3M 401Q 1200 grit wetordry paper to relieve the sharp edges, and to make a very minor correction on one side of a scale.

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Shown on page 16 of our latest catalog.