String Action Gauge

  • 157 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 157 Reviews
Displaying 5 of 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
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Should have bought one ages ago

By Lance Link from Japan
(Customer's Reviews) Wednesday, January 16, 2013

In general, if you are setting up your own guitar, you should have a string action gauge. I've been going without one for decades, and while "feel" is of course the most important aspect of action, it's really nice to have an objective reference point to know mathematically where your action really falls and whether or not it really has become worse when you instinctively feel like it has. Specifically, this StewMac gauge is exactly what you'd expect it to be, a precise and sturdy metal gauge, in a convenient size, with a lot of info available on all its edges. It can be a little hard on the thicker strings to read where your action lies, but that's going to be the case with any gauge due to the small increments you're working with. I use mine a LOT, especially as here in Japan, in an old-style Japanese house, the climate in my music room changes drastically and I'm adjusting the action almost weekly.

Cool Tool!

By LDT from Southaven, MS
(Customer's Reviews) Wednesday, January 16, 2013

Makes set up a snap!

Great Product!!

By Matan from Dimona, ISR
(Customer's Reviews) Saturday, January 05, 2013

Accurate and Small Great for Setup Work!

Great item and a time saver 

By sofislele from Athens, Greece
(Customer's Reviews) Saturday, December 29, 2012

I got this one in metric and the setup now seems like a game. Great accuracy.

A great tool to have

By J K Jones from Los Angeles, CA
(Customer's Reviews) Wednesday, December 26, 2012

As I start to do more of my own setups, this is a great help.

In constant use

By Reid Hall from New York City
(Customer's Reviews) Tuesday, November 13, 2012

These things got used so much I have to keep two around.

Handy piece of kit

By KC Sligo from Ireland
(Customer's Reviews) Saturday, November 03, 2012

Love this gadget and it is much easier to read than those small rulers

One very handy little tool

By Will Hirsch from Arcata, CA
(Customer's Reviews) Wednesday, October 24, 2012

Like many folks, I suspect, I made do with a pocket rule or sometimes even strings of differing gauges when doing setup work. I finally broke down and treated myself. It really does work better, has lots of different scales with which to measure and works great. Wish I'd just gotten it years ago.

This is a must have

By billmcalister from UK
(Customer's Reviews) Thursday, October 04, 2012

This gauge means that you can check your string action height with a quick glance. Brilliant.

Invaluable tool

By Dingobass from Perth, Australia
(Customer's Reviews) Wednesday, September 26, 2012

This is one of my favorite tools for set ups. No more guess work. Simple to use and very accurate. Buy it now!

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