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 10 of 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Write a review

String Action Gauge

By Pat Green from UK
(Customer's Reviews) Friday, December 23, 2011

Usually I set up my guitars basically by trial and error and bits of paper with pencil marks on them for string height etc. However I recently purchased the String Action Gauge and it makes things very much simpler and much more consistent. As a result I have reset up 4 guitars since getting it and eventually I'll work my way through the rest.

Gotta have a dozen!

By JLondon from Owensboro, KY
(Customer's Reviews) Wednesday, December 21, 2011

Why? So I'll have one for the rest of my life if they quit making them - that's why! One would easily last a lifetime on the shop table, but I want to carry one in my billfold like a credit card and I'm afraid the ink and markings will wear off (probably won't though). This is the single most all-round valuable tool on this website. I promise!

String Action Gauge

By giuspe from Milan, Italy
(Customer's Reviews) Sunday, December 18, 2011

Simply excellent and especially fast to be used. A++++

String action gauge

By Mateo de la bodleiana from Oxford, England
(Customer's Reviews) Saturday, November 19, 2011

Only a very simple product, but a very necessary one if you want to get into setting your guitar up properly. The quality of the product is excellent with all the markings clear and accurate. The rudimentary instructions and benchmark values are also very helpful. The purchase interface (the website), considering I am buying everything from "overseas", is second to none. I have bought before from firms in the USA and have had endless problems. This firm has got it right. Thanks for the service you offer.

S.A.G. rules the bOard!

By jiROck Custom from Philippines
(Customer's Reviews) Sunday, November 13, 2011

it makes your life simple. no more guessing... and by the way it includes "forbidden notes"...LOL. just get one and you'll know whats the Forbidden notes. ;p

easy to read

By Set-up Technician from Solon,Ohio
(Customer's Reviews) Sunday, November 06, 2011

Worked great.

Super Setup Tool

By Slip'ry Dan Weisberg from San Jose, CA
(Customer's Reviews) Friday, November 04, 2011

This gauge has been incredibly useful! It's the easiest way to measure string height at any given fret. I got the metric version, and I use a table to convert to inches. Highly recommended!

Great for setups

By tb from Portland OR
(Customer's Reviews) Friday, October 21, 2011

Great tool for quickly measuring string height after making saddle or truss rod adjustments. It not as active as a file or saw but it's extremely handy to have available. The conversion chart on the back was a nice use of space as well.

String Action Gauge

By Doug G from NY
(Customer's Reviews) Saturday, October 08, 2011

Love it. Works great.

Class Action

By D.A.D. from Fullerton CA
(Customer's Reviews) Friday, September 23, 2011

Hello again Stew Mac, along with the nut files i purchased i also bought the "String Action Gauge" which helped to dial in the action i desired. It is a very handy tool again to take the guess work out of the job. Recommended for anyone who wants to make the job easier.

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Shown on page 16 of our latest catalog.