Understring Radius Gauges

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Set of 9

Item # 0353
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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.

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


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?”

Customer Reviews

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  • 4.95 average rating from 143 reviews
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These fit under the strings, but won't fit inside some bridge plates.

(Customer's Reviews)

Nice item, but easily bent, so hang them up in a safe place. They will readily tell whether the bridge radius matches the finger board radius, & what is what. I don't buy into pickup pole piece height, because I use my own formula for that, and the same for final bridge & nut radius. I give the bass strings more room to vibrate on a low action guitar, and I tend to follow the Fender staggered pole piece concept for pickup pole heights, but these are still a great item to have on hand.


A must for set up

(Customer's Reviews)

This is a must if you set up your own guitar.


Under string radius guages

(Customer's Reviews)

Very precise well made tool These guages are an absolute necessity for any guitar technician You save time and have a perfect string radius If aperson gets in abind and has to make a fret board Or combo fret boards Excellent tools As are allthe videos produced by Stewart MacDonald Your company has aided me alot Thank you.

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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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