String Spacing Rule

  • 122 Reviews
  • Write a review

Get accurate string spacing without calipers, calculators or shop rulers.

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String Spacing Rule

Item # 0673
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Quantity: 20


String Spacing Rule

Dan Erlewine shows how to use the String Spacing Rule to quickly locate the strings on a guitar nut. He also explains the problem with using equal spacing.

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Get accurate string spacing without calipers, calculators or shop rulers.

Our laser-etched stainless steel String Spacing Rule quickly finds the right spacing for just about any stringed instrument. It does all the math for you: proportional slot spacing automatically compensates for string diameters, from treble to bass, so the thicker strings won't seem crowded to the player.

The problem is: if you space the strings equally, they don't feel equally spaced. The thicker bass strings seem crowded together. Each gap between strings has to be slightly different to feel right to the player. How do you calculate this? The String Spacing Rule takes care of it, for guitars, basses, mandolins, and banjos.

Fast. The String Spacing Rule is slotted so you can quickly mark the string positions onto the nut. Use a scribe instead of a pencil, and it creates extremely accurate starter grooves for your nut slotting files.

Easy to use. Mark the two outer string positions onto the nut. Slide the rule over the nut to find a set of slots that matches your two marks. Now just scribe or pencil the string positions onto the nut! No measuring, dividing or calculating — the rule does the math for you.

Accurate. The rule's slots are laser-cut in a continuous scale that wraps around both edges of the rule (our thanks to luthier Kevin Ryan for creating this tool). Proportional slot spacing subtly compensates for the diameters of the individual strings, from treble to bass, to give the right feel and playability.

Not just for nut slotting. You can use the String Spacing Rule to notch Tune-o-matic bridge saddles, to lay out bridge pin holes, and when notching archtop guitar, banjo, mandolin and violin bridges.

The String Spacing Rule is made of laser-etched flexible stainless steel that conforms to flat or arched surfaces. Instructions are included.

The String Spacing Rule is included in the Essential Nut Making Tool Kit, which has all the basic tools you'll need for shaping, string-spacing, slotting and fitting string nuts like a pro.

Trade Secrets! Newsletter

Using the String Spacing Rule for guitars and mandolins

Erick Coleman uses Kevin Ryan's proportional string spacing rule for more jobs than Kevin ever expected: 12-strings, mandolins, bridge saddles... Plus: an explanation of the difference between equal spacing and proportional spacing.

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 Spacing Rule Instructions

The String Spacing Rule locates string positions so that heavier strings get the wider spacing they need.

Ratings & Reviews

String Spacing Rule

  • Based on 122 Reviews
Displaying 11 of 13 1 2 3 4 5 6 7 8 9 10 11 12 13
Write a review

Nothing else like it

By Parhal from Wisconsin
(Customer's Reviews) Monday, January 31, 2011

This is a great tool. There is no other tool that so easily helps to mark out spacing measurements. That said, it can be a little clumsy to bend the rule over a curved piece of material and hold it in place while trying to mark it. Other than that, a great tool.

A Winner

By GOA Guitars from Bris Australia
(Customer's Reviews) Tuesday, January 04, 2011

Everyone who works on guitars needs this rule,spot on nuts every time. So easy to use thanks Dan and Stewmac

Rule of strings

By Tinkering picker from Pomeroy, Ohio
(Customer's Reviews) Friday, December 31, 2010

Man am I glad I found this thing. I have made several nuts and bridges before and had to always calculate the spacings. This tool is so simple and easy, plus a time saver. Basically for a 6 string guitar, all you need to know is how far you want the 1st and 6th strings,(the E strings) to set from the edge of the fret board. Line the string rule up and mark the other string placement and groove them out. When I used to calculate the spacings, I never even thought to consider the string thickness. The string rule does that as well. If you make many nuts and bridges this is a great tool to have, a must. Thanks StewMac


By Pat from Cumberland, MD
(Customer's Reviews) Thursday, December 23, 2010

This thing works great. What a simple, brilliant idea. It takes the guesswork out of string spacing.

A real time saver!

By Cone Guitar from Kihei, HI
(Customer's Reviews) Saturday, December 11, 2010

Instead of laboriously calculating the correct string spacing, and then very carefully etching the nut before cutting the slots, this rule does all that and remembers it for the next time. A simple colored dot with a Magic Marker saves the specific setting for the next time. Produces a perfect string spacing.

String spacing ruler

By JimLam
(Customer's Reviews) Monday, December 06, 2010

Made determining string spacing so simple. Can just eyeball the spacing you want and mark the nut from there. Paired with the pre-shaped nuts, making a nut is no longer a problem.

Almost perfect gadget

By Arthur Z from New Orleans, LA
(Customer's Reviews) Friday, December 03, 2010

I am dabbling with guitar refurbishment and assembly using parts gathered here and there. This string spacing rule is essential for cutting a string nut from scratch. My only (small) complaint is that it has no reference marks to identify the slots you select--I had to put tape down the middle and use colored dots in order to recall the dimensions I had selected. Perhaps a later model can include reference letters or numbers down the middle so that the user can note that position "B-6" worked best for a particular application.

Chris Pedersen, OZ

By tzen from newcastle australia
(Customer's Reviews) Tuesday, November 30, 2010

THIS makes me accurate, every time. Great thanks very much, perfect for any guitar builder at any level


Great tool!

By stepuc from italy
(Customer's Reviews) Monday, November 29, 2010

Accurate string spacing! Great tool!


By Johnny Star from Napa, CA
(Customer's Reviews) Friday, November 26, 2010

Wish i would have came up with this tool it works sufficiently. Its a must when it comes to making a guitar nut

Displaying 11 of 13
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