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

Cool tool!

By AJ from Brisbane Australia
(Customer's Reviews) Tuesday, September 20, 2011

Very clever tool, a bit smaller than I expected, but INVALUABLE nonetheless.Thank you for re-invigorating my passion for helping artistic weapons-of-expression sing to the best of their ability, Stew Mac RULES!!!

great investment

By Stoner Antique from Holiday'Florida
(Customer's Reviews) Wednesday, August 31, 2011

This all in one tool is great addition to my tool chest.Makes set ups so much easier no guess work.

My Favorite Setup Tool

By Middleton Guitars from Southern California
(Customer's Reviews) Tuesday, August 30, 2011

This is like a Swiss Army Knife (without any moving parts). This is my most heavily-used item for setups. I'm going to purchase more of these to have on-hand at other locations. This takes the place of a ruler, feeler-gauges, a straight-edge, and calipers!

Invaluable for string changes

By Teeky from England
(Customer's Reviews) Sunday, August 14, 2011

This is a superb little tool that easily slips in your accessories case.

Yes you can check your action at any time but especially useful when you change string gauge. Good plan to check the string height at 12th fret before the changing strings. A different gauge invariably changes the tension on the truss rod and it's as well to check to see if any adjustment is required on the truss rod.

This tool makes it easy to check before and after to ensure that your instrument plays as well after (if not better than) as before.

Great for setting pickup pole pieces too.

Great tool - must have for set ups

By blam from edmonton
(Customer's Reviews) Wednesday, August 10, 2011

This is great for set ups. I used to use feeler gauges and calipers and plain rulers. This tool blows them out of the water for ease if use.

Excellent Tool

By Slip'ry Dan Weisberg from San Jose, CA
(Customer's Reviews) Monday, August 08, 2011

The String Action Gauge is a must have tool for guitar setup. I chose the metric version, since it's better for measuring small distances. Conversion charts from metric to inches are widely available, so it wasn't a problem when comparing my results to the recommendations which are often published in inches.

I also purchased the StewMac Understring Radius Gauges, and the CruzTools GuitarTech Guitar kit, which I found on Amazon. The CruzTool kit has the wrenches needed to adjust neck truss rods, as well as a metal ruler, feeler gauges, and some other setup tools in a nice case.

These tools allowed me to setup my Tele and my Musicman bass so that they play great! Even if your guitar is brand new, you can make it play much better with proper setup.

I also bought the book How to Make Your Electric Guitar Play Great by Dan Erlewine. You can probably setup your guitar without it by using the Web and the instructions that come with the CruzTool kit, but the Erlewine book puts it all in one place, and gives some setup specs and problem solving suggestions as well.

One area that the book was a little weak on was the topic of Neck Angle. After adjusting my bass guitar's truss rod, I still needed to lower the bridge to get the right string height, but the bridge pieces were as low as they could go. So instead I adjusted the neck angle which solved the problem. Luckily, I found some good info on the web about this.

A must have

By Tarz Tarz an mo' Tarz from Little Rock
(Customer's Reviews) Thursday, August 04, 2011

I have more than one. I recently moved and my tools are still packed away. I needed to do a proper setup on a new guitar and I was unable to find the box where my stuff is packed so rather than do it without a string action gauge, i bought another. That's how much I feel this thing is a must have!

String action gauge

By Steve Fields from United States Portland OR
(Customer's Reviews) Thursday, July 21, 2011

I absolutely love this tool, setting string, saddle and pole piece height is a snap now

VERY handy tool, but why does it cost $19?

By RickinVirginia from McLean, Va
(Customer's Reviews) Wednesday, June 22, 2011

If you "mess around" with guitars at all, this tool is very, very handy, no question about it. But I do not understand the price. Were it plastic, I would expect it to be given away at guitar shows. Being metal ups the price some but THAT much? Even so, why does one have to buy two if you need English and Metric scales - why are they not on opposite sides. Don't get me wrong - I like it and use it often but the price seems quite high for what it is.

Usually stew mac tools are second to none.

By uk_blaster from Providence, RI
(Customer's Reviews) Wednesday, June 22, 2011

This item gets the job done, but I've got to say, the build quality is fair at best.

Unlike the shiny, silvery to almost whitish metal shown in the photos on this page, the gauge I received is very dark metal, making the almost equally dark printed markings on the gauge very difficult to read even under my bright, workshop lighting.

In my attached photo you can see my new, just removed from the Stew Mac packaging, action gauge side by side with an two year old, $10 aluminum architectural scale.

I think the photo pretty much speaks for itself.

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Shown on page 16 of our latest catalog.