Understring Radius Gauges

  • 142 Reviews
  • Write a review

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.

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Set of 9

Item # 0353
In stock, ready to ship!



17" gauge only

Item # 0352
In stock, ready to ship!


Total: $0.00
Quantity: 20


Radius gauges for guitar work

Dan Erlewine demos the three kinds of radius gauges for setup and fretwork.

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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.

Set of 9 now includes new 17" radius for Ibanez guitars!

Find your fretboard radius, and set your bridge saddles to match. They're handy for matching pickup polepiece heights to the arc of the strings, too. Precision laser-cut from .050" stainless steel.

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

They'll work for string spreads and fingerboards up to 2-5/8" (66.68mm) wide.

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Ratings & Reviews

Understring Radius Gauges

  • Based on 142 Reviews
Displaying 12 of 15 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Write a review

Why did I wait so long?

By Dave Sparrow from Evesham, UK
(Customer's Reviews) Monday, April 04, 2011

These little beauties are an absolute treat - they've saved me so much time already and they help me produce a better setup every time. So much easier than fighting with the ruler! And being such a reasonable price, I wonder why I didn't get them earlier!

A must for proper set-ups

By Froggy3018 from Aberdeen, NC USA
(Customer's Reviews) Thursday, March 31, 2011

These gauges are easy to use and make set ups more refined. I highly recommend these!!

Pour un rTglage parfait!

By Bluester from Switzerland
(Customer's Reviews) Wednesday, March 30, 2011

Ce petit instrument permet d'identifier la courbure de la touche et de rTgler parfaitement la hauteur des cordes. Tout simplement indispensable !

Radius Gauges

By Peter Coplin from Princeton, New Jersey
(Customer's Reviews) Sunday, March 27, 2011

When selling guitars people often ask the neck radius. It seems to be very important to them. With these you can tell in an instant. I measure at the 12th fret. Very precise.

Radius gauges

By Scott Miller from WI
(Customer's Reviews) Sunday, March 20, 2011

I was having a hard time with the B string on my Lavavee acoustic occasionally buzzing from not seating on the fret with certain bar chords. The under string radius gauge showed that the saddle for the B string sat several thousands on an inch proud to the other strings. A slight adjustment to the saddle corrected this and now the guitar plays like a champ!

Understring Radius Gauges

By Giovanni from Milan Italy
(Customer's Reviews) Wednesday, March 16, 2011

A must have for setup.

Strong and very useful.

Fantastic Product!

By Robbin St+Ñhl from Sweden
(Customer's Reviews) Thursday, March 10, 2011

Essential for any guitar tech! No reason to buy the radius gauges, these ones does it all. The only thing I'm missing, as with all radiused Stewmac products is one for the Ibanez 430mm radius.

Great tool

By tb from Portland OR
(Customer's Reviews) Wednesday, February 23, 2011

Well made tool with rounded edges and clearly labeled. Radius is the same on top and bottom so checking fingerboard radius, bridge radius, or under string radius are all a snap. Will have these as long as I work on my own equipment.

Understring Radius Gauges

By KBarry from Altamonte Springs, FL
(Customer's Reviews) Wednesday, January 26, 2011

Very useful in determining fretboard radius and then setting saddles heights and pickup poles

Radius Gauges Understring

By Bob Barcus from Dana Point Ca
(Customer's Reviews) Sunday, January 23, 2011

These are 3 in one tools I use them to find the Neck radius,Nut Radius Bridge, ect. You can even Make other gauges out of Hard Cardboard. Seting the (Radius) to your strings,I could Never do it without these. This should be one of the first tools to buy. My guitar never felt easier to play, and they will last you a life time

Displaying 12 of 15
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Shown on page 17 of our latest catalog.