String Action Gauge

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Item # 0670
In stock, ready to ship!




Item # 0670-M
In stock, ready to ship!


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String Action Gauge

About This Item

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.

Metric String Action Gauge

How to determine string action with the Metric String Action Gauge.

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  • 4.88 average rating from 169 reviews
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Well-made, useful tool

(Customer's Reviews)

This gauge has a great feel to it. Graduations are clearly defined. Although I appreciate the design with 64ths set up for L/R measuring, I would prefer one of those end "sets" to be in 32nds.


A Must

(Customer's Reviews)

This gauge is a must whether you're a luthier or not. If nothing else, it will get you in the ballpark so you can set string height to where you like it. It really came in handy when I was setting up the Tune-O-Matic bridge on my LP Gibson. I don't regret purchasing this gauge.


Easiest way to gage string heights I've found.

(Customer's Reviews)

For years I have used a lot of methods to gage string heights at the octave. I have run the gamut from dial calipers to coins. To date, this is the easiest method of reading string heights I've found yet. No problems keeping it level on the frets.

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StewMac PDF Catalog, page 16 See String Action Gauge
on page 16 of our StewMac Catalog PDF

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