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 7 of 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
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Best tool for a good setup.

By Wv Bluesman from Suwanee, Ga
(Customer's Reviews) Saturday, July 07, 2012

Cheap, easy to use, will help you get great results with your setups.


By Seth Naugler from Bucks County, Pennsylvania
(Customer's Reviews) Thursday, July 05, 2012

If Stewart-MacDonald were ever to go out of business, there are certain tools that would be very difficult to replace. This is one of them. I have three of these. I use mine most of the time for measuring string height over the 12th fret and it does that exceedingly well. The gauge lays along several frets which guarantees that the rule is exactly perpendicular to the fingerboard, reducing potential error. On the back is a table listing quick conversions between fractions of an inch and metric equivalents which is extremely useful; I use it all the time. All markings on the rule are etched and permanent. Great tool.

Very Handy

By Al McKay from Australia
(Customer's Reviews) Friday, June 29, 2012

Another great tool for the box of tricks. U-beaut handy item.

Quick and easy

By Coffeeman from Lexington,Ky
(Customer's Reviews) Saturday, June 23, 2012

Great little tool. Quickly "eye ball" a setting and quick adjust tool.

Best tool i have.

By abilbay from Ft Worth, TX
(Customer's Reviews) Monday, June 18, 2012

Hands down the most used and best tool I have. It is simple to use and has improved the speed and accuarcy of my setups. I also use it to make adjustments to saddles, nuts, bridges, pick-ups, etc.

Can't put it away

By thrash50
(Customer's Reviews) Thursday, June 07, 2012

Great tool for set ups,and I also use for marking nuts before cutting With all the different measurements, and converter on back easiest way to check any gap or space you can think of, I find myself constantly checking action, neck bow, pickup height on my guitars and friends guitars. I'm a lefty who doesn't mind converting right hand guitars myself.

String Action Gauge

By Brian C from CT
(Customer's Reviews) Thursday, June 07, 2012

Super quality tool. I am a "happy camper" with it.

Math made simple

By Little Crow from Atlanta, GA
(Customer's Reviews) Friday, June 01, 2012

This is one of the most useful measuring tools you can have when it comes to instruments. If it is small and needs to be measured in any way, this is your friend.

String Action Gauge

By byerek from Spain
(Customer's Reviews) Thursday, May 24, 2012

It¦s a perfect tool.


By kennylee from aberdeen maryland
(Customer's Reviews) Monday, May 21, 2012

This takes the guess "eye ball" out of my set ups and also gives Me a reference point for my customers set ups when they come back measure write it down and i even cross reference customers likes to get all there instruments to feel right. Me and my customers are glad i purchased this

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Shown on page 16 of our latest catalog.