Understring Radius Gauge - Wide - for guitar and bass setup - Set of 9

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  • Wide Understring Radius Gauge Set
  • Set of 9
  • 7.25”, 9.5”, 10”, 12”, 14”, 15”, 16”, 17” and 20” radii
  • Laser cut stainless steel
  • Etched with radius on handle
  • .051” (1.3mm) thick
  • 3 3/4” (94.6mm) wide
  • .100" (2.6mm) thin

The new wide and thin radius gauge set. Wider for 7/8 string guitars and 5/6 string bass guitars. Thinner than the original so it slips easily between the string and the fretboard for easy measuring of the fretboard radius!  

These come in the most popular fingerboard radius and make it easy to measure the radius from either above or below the strings. Use these to accurately setup your guitar bridge saddles to match the fingerboard radius.

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  • 5
    Wide Understring Radius Gauges

    Posted by pfkbass@verizon.net on Dec 29, 2021


  • 5
    Amazing value. Amazing quality

    Posted by Fishtacular on Sep 14, 2020

    I had a difficult time measuring the radius on a guitar. Documentation was lacking. The year before this model was 15" and the year after was 17". Was it one of those? or something entirely different? I tried using some gauges I purchased from somewhere else. It was very difficult to see the difference, but... I eventually noticed there was a problem with my gauges. The 15 I had was slightly flatter than the 17. So, even though these gauges said 15, I couldn't trust that measurement at all. Very disappointed. Because of the amazing quality in other tools purchased from Philadelphia Luthier, I decided to order these and was very satisfied, again, with my purchase. The maximum difference between a 16" radius and 17" radius is less than 0.002" over a 2 inch wide piece of neck. This is a fraction of the thickness of a sheet of notebook paper(0.003"). By shining light from behind, I was able to see this neck was 17" radius, and not 16". I was also able to see it get closer as I went from 15 to 17. Remember how small these tolerances are. These are excellent gauges. I was able to use these gauges on a very low action guitar with the strings on by sliding them in sideways from the side, and rotating up to have the handle in the middle. Philadelphia Luthier ships amazingly fast.

  • 5
    Wide Radius Gauge

    Posted by James Bettincourt on May 14, 2020

    Great product and company!

  • 5
    Worked perfect

    Posted by Ed on Apr 26, 2020

    Gave me an accurate guide to fix my bridge's string radius. Came with a key ring to keep them organized. Also Philly Luthier shipped very fast and well packed.

  • 5
    Understring Radius Gauge-Wide

    Posted by Jeffery on Nov 3, 2019

    Theses work great for 6 string basses. Well made, will last a lifetime.

  • 5
    wide radius guage reviews.

    Posted by jbone on Apr 12, 2019

    these work well. legibly marked and pretty durable. hang on a peg for benchwork or ganged together in a kit for the travelling tech.good value, would buy again from these guys.

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