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!


Total: $0.00
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 2 of 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
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multi-purpose guage

By pedalman from Boston area
(Customer's Reviews) Saturday, December 14, 2013

A high quality, practical rule. Use the horizontal string guide to hone in on relative height, and the 1/64" for more accuracy.

Great Measure

By zapkat from Sierra Vista, AZ
(Customer's Reviews) Sunday, November 24, 2013

I like so many others was using a six inch steel rule. Now that I have the String Action Gauge set up of stringed instruments is much easier.

Great Gadget

By J Mac from Brisbane
(Customer's Reviews) Sunday, November 03, 2013

easy to use and repeatable !

Easy and effective

By Robert1986 from Kalispell, Montana
(Customer's Reviews) Monday, October 28, 2013

I've been using a small 6 inch steel rule to measure string height. What a pain. This little gauge though quickly and accurately lets me find the correct height of the strings. Plus many other uses. I even use it to set up my band saw and router.

Works great for my needs

By wizard1325 from Tampa, FL
(Customer's Reviews) Monday, October 21, 2013

Love it should have purchased the standard version instead of the metric version because all my guitars are made in USA.

Totally Basic

By pablopuerto from Chile
(Customer's Reviews) Thursday, September 12, 2013

One of the first I bought..Excellent...I just recommend a different color for he numbers. Difficult to see.

bought it on impulse. 

By XevKai from St.Clair Shores, Michigan
(Customer's Reviews) Wednesday, September 04, 2013

So used to using just a regular 6 inch scale for set up measurements. I am still finding myself to be forced to use this little guy. I think in the sweet spot area, say .050 - .070 there should be .005 incriments.

string action gauge

By stealth9tn from Ohio
(Customer's Reviews) Sunday, September 01, 2013

This is a must have tool and it is very easy to use with a nice conversion chart on the back.

Level headed

By Phillms from Albury UK
(Customer's Reviews) Saturday, August 10, 2013

I am always imprest with the tools that arrive from you guys clean lines and clear to see info on how to use the the string action gauge makes life so much easier giving more time to fit more in my day! I have many tools now and every time they arrive it is good to see the extra effort made so we all know how to use the new tool if we have not seen one before. so clear every time . Kind regards Phill ms England

Get one, you'll use it a lot!

By Dave Ward from Oklahoma City, OK
(Customer's Reviews) Tuesday, August 06, 2013

Yet another handy dandy "Must Have" from Stew-Mac. Usually when people come in asking for a setup, they're actually asking me to "fix" a guitar that plays badly because they've tinkered with it themselves and do not know how to get their desired results. Being a long time guitar player, I generally know what other guitar players will like. Some folks do not want the action changed AT ALL. This gauge allows me to measure the existing action and return it to the original specs with ease.

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Shown on page 16 of our latest catalog.