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 15 of 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
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By DM from NS
(Customer's Reviews) Tuesday, January 04, 2011

One of my "desert island" tools!

string action gauge

By hbgb from New Braunfels,Texas
(Customer's Reviews) Thursday, December 23, 2010

After using a pocket clip style ruler to set up guitars and dealing with the shadows,hold it straight,wobble it to find your height, this tool is nothing short of perfect and fast. Critical measurements are a breeze. Of all the tools I bought to do neck and fretboard work this gave the biggest bang for the least bucks. Now that I'm used to the .010 bar graph, measurements are super quick. You will love this tool.

String Action Gauge

By Roy Bullis, Onyx Forge Custom Guita from Laguna Hills, CA
(Customer's Reviews) Wednesday, December 15, 2010

Used at Onyx Forge Custom Guitars for a variety of uses. The conversion chart on the back comes in handy too. I would rate this little guy a 5 if it had come with a small hole punched in it for hanging.

A very handy set up tool.

By Ryan Rua from USA
(Customer's Reviews) Thursday, December 09, 2010

I've set up a lot of instruments, I've made various string action gauges of my own. They all work well enough, but I decided to try this since there is a metric version now. I really like using it. It is not essential, but it does work very well and makes set up easier, faster, and more precise. Putting an end to the ruler wobbles is well worth the price. Now that I have this it will probably be all that I use from now on.

OK, I was wrong.

By goodwill559 from Fairfield, CA
(Customer's Reviews) Thursday, December 02, 2010

It really IS much better than using a small steel ruler! It's so very useful. I was skeptical at first, but I'm a believer now. Highly recommended.

Just Get It

By Jukebox John from Shutesbury, MA
(Customer's Reviews) Thursday, November 18, 2010

This gauge has so many uses - set ups, locating drill holes, etc. Elegant and has different scales. You need it.

String Action Gauge

By LJ from Crete, IL
(Customer's Reviews) Thursday, November 18, 2010

While a bit smaller than I expected, this is a very nice and very useful tool. I can see using this in many ways regularly. The size may be a benefit, too, because it is pocket or wallet size and it would be very easy to take it along when buying or evaluating a guitar.

much needed tool for your shop

By Bill's repair from Madisonville,TN.
(Customer's Reviews) Sunday, November 14, 2010

The string action gauge is a must need tool for setting up your guitar. It takes the guesswork out of trying to figure out the height that you need at the twelfth fret to keep your strings from buzzing if your guitar neck is straight. Thanks for making my job easier.

Action gauge

By John Cross from Devon, Alberta
(Customer's Reviews) Monday, November 08, 2010

Very easy to use and read. I find myself looking for things to measure. I should have bought it sooner.

String Action Gauge 

By Beat St++ssi from Baar, Switzerland
(Customer's Reviews) Sunday, October 17, 2010

Thus one can examine the action simply with each stringed instrument! Very much helpful!

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Shown on page 16 of our latest catalog.