String Spacing Rule

  • 121 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 121 Reviews
Displaying 12 of 13 1 2 3 4 5 6 7 8 9 10 11 12 13
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Spacing Rule

By Elias Preston from St. Louis, Missouri
(Customer's Reviews) Friday, October 29, 2010

The String Spacing Rule came with good instuctions and is a very easy tool to use. I found that it speeds up the whole process of making new nuts. Now I don't have to guess or eyeball where I want string placement. Great tool!

Sight saver

By Bigriver Guitars
(Customer's Reviews) Friday, October 22, 2010

At 60, my eyes can't take the strain and I needed something to make string spacing easier. This is the ticket. I should have got one of these while my eyes were good, They'd probably still be good!!

String Spacing Rule

By naccoachbob from Nacogdoches, Tx
(Customer's Reviews) Wednesday, October 13, 2010

I decided to try spacing my strings mathmatically. It can be done. But I found that I couldn't be precise enough with my ruler and pencil even with 64th's. Hated to spend money on something that I'm only going to use 4-5 times (amateur luthier), but the minute I got it, I was glad I did. It's stupid easy to use, and very much worth it to me now. I highly recommend it even for a couple of builds. I know it took some effort to create this rule, but the price is still a bit high. Keeping it from getting 5 stars from me. Does what it's supposed to do and does it well, though.


By Fret Tech from NJ
(Customer's Reviews) Thursday, October 07, 2010

This is a must-have time-saving tool for the working pro tech/luthier. The only caveat is that at the narrow end of the scale, the center-to-center E-to-E tick marks for a 6 string is 1.328", and some (very very few!) necks have narrower nuts that the scale can't handle. Still, the best spacing tool around for nuts and saddles.


By Seth McCombs from East Rochester, NY
(Customer's Reviews) Thursday, September 30, 2010

A clever little ruler! I don't know how i went without it!!

Useful Tool

By Dr H from Earth
(Customer's Reviews) Tuesday, September 21, 2010

Does exactly what it's supposed to do, and well made (durable). It is a bit pricey for a ruler, so if you're just doing one nut it's probably not worth it. But if you have a dozen to do, it will pay for itself in the time saved. Works for spacing strings on bridge saddles, too. I agree with the first reviewer, though -- when you start applying it to OEM nuts, it's hard to resist wanting to readjust most of them. :-)

Exceeds Expectations

By Joe Dowd from Edwall, WA
(Customer's Reviews) Thursday, September 09, 2010

The only problem with the string spacing rule is if I put against OEM nuts I want to re-do every single nut I encounter. Well-made, easy to use, can write on it with a pencil.

No Brainer

By Caravella Guitars from East Meadow, NY
(Customer's Reviews) Wednesday, September 01, 2010

Most of my guitars get custom neck widths for my clients. Using this it's a breeze determining the proper string spacing. Saves time and effort.

wonderful tool

By Gilson Russo from São Paulo Brasil
(Customer's Reviews) Friday, August 13, 2010

It's a wonderful tool, isn't it? You don't lose any time to spacing strings on nut's project, without measures or calculus. I'm very glad with mine.

Just as expected

By Christian Cornejo from Astoria, NY
(Customer's Reviews) Wednesday, May 26, 2010

It's a little pricey as far as a ruler goes, but it works just as expected and is extremely easy to use. It eliminates the headache and the math of calculating proper string spacing, and has a large range of string sets.

Displaying 12 of 13
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