Understring Radius Gauges

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Understring Radius Gauges Standard width, set of 9

Standard width, set of 9

Item # 0353
In stock, ready to ship!


Understring Radius Gauges Extra-wide, set of 9

Extra-wide, set of 9

Item # 0359
In stock, ready to ship!


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Understring Radius Gauges

About This Item

Fast, accurate bridge saddle adjustment.
Each of these unique gauges has an accurately radiused arc on both the top and bottom surfaces, and is shaped to fit easily under the strings.

Use the bottom curvature to determine your fretboard radius, and the matching top curvature becomes a reference for setting string saddle heights for best playability.

Low profile fits tight spots. The slim shape of our understring gauges allow you to read the fretboard radius even with the strings on! This is also handy for matching pickup polepiece heights to the arc of the strings. And setting bridge saddles is easier than ever.

The set of 9 gauges includes:
7-1/4", 9-1/2", 10", 12", 14", 15", 16", 17" and 20" radii.

Standard width 6-string guitars and most 4-string basses—spans a string spread up to 2-5/8" (66.68mm).

Extra-wide covers string spreads up to 3-3/4" (95.25mm)—enough for 4-string, 5-string, and many 6-string basses. They'll also handle 7-string and 8-string guitars.

Stainless steel.


Trade Secrets!

Trade Secrets!

Fixing fret buzz: raising the saddles

A P-Bass with fret buzz: Dan Erlewine fixes his brother’s bass, and answers the question, “To get rid of this fret buzz, should I adjust the saddles or the truss rod?”

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  • 4.95 average rating from 147 reviews
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Understring radius gauges

(Customer's Reviews)

Well done, useful!


Indispensible for a proper bridge setup

(Customer's Reviews)

I bought these to help me set up my Fender Precision bass, which has a fingerboard radius of 9.5". First off, the only gripe I have is that these things don't seem to be available individually. I have two basses currently, and they both have the same radius so I don't see myself needing anything except the 9.5" one. I guess I'm supposed to feel prepared if I ever buy an instrument with other radii.
In any case, I've found that the 9.5" gauge makes setting the individual bridge barrel heights a breeze, and I feel assured that all four of my strings are exactly the same height off the frets.
They seem to be well-made, with no rough edges or burrs to interfere with contact with the wooden fingerboard.
I will be using these things for all future setups.


Great tool

(Customer's Reviews)

This is a must have tool, removes all the guessing required!

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StewMac PDF Catalog, page 17 See Understring Radius Gauges
on page 17 of our StewMac Catalog PDF

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