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 9 of 13 1 2 3 4 5 6 7 8 9 10 11 12 13
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Happy Camper

By gr82cucuz from Pahrump, Nevada
(Customer's Reviews) Thursday, August 04, 2011

This product is, as always from StewMac, great quality. But I am always impressed most by their speedy service.

mr fix it .

By derek from england from england
(Customer's Reviews) Monday, August 01, 2011

hi ,i thought the string spacing rule was great done the job ,and well worth the price ,

Must have

By Chucka from Melbourne, Australia
(Customer's Reviews) Monday, August 01, 2011

The first thing any guitar tech should buy before starting out. Wonderful product. Ruler very flexible so good for marking lines on curves too.

string spacing ruler

By Spooky Dave from Michigan
(Customer's Reviews) Monday, July 25, 2011

Awesome. Easily figure nut slot spacing. Works like a charm. Worth the money to save the time and headache of trying to 'eyeball' it


By desmatic from Wales, United Kingdom
(Customer's Reviews) Tuesday, July 05, 2011

Great little gadget for setting custom string spacing.

Hard to read but useful

By MidnightGuitarRepair from Rochester NY
(Customer's Reviews) Tuesday, July 05, 2011

Hard to read, making it somewhat frustrating to use. However, string spacing turns out great when using this rule.

Super handy

By flatfootjohnny from London
(Customer's Reviews) Thursday, June 23, 2011

AS i generally make one off instruments so no two necks are exactly alike, this rule is great and saves a lot of time and frustration.

String Spacing Rule rules

By Phillip B. Gifford from Lebanon, Ohio USA
(Customer's Reviews) Wednesday, June 08, 2011

I used the string spacing rule on my first homebuilt F-5 mandolin which had a nut .090 wider than the normal 1"-1/16. I've never been able to lay-out string slots so perfect until now. I am a toolmaker by trade and strive to get things perfect. This tool makes it easy to do work like a pro. Thank You Stew-Mac

A Must Have

By Wimsatt Instruments from Nashville, TN
(Customer's Reviews) Friday, May 27, 2011

Put away the calipers. This tool gets it right every time. There are a handful of tools that every busy repair shop should have. This is one of them. I use it in my shop daily and so do my employees.

Absolutely Useful

By toneage from canada
(Customer's Reviews) Thursday, May 12, 2011

What a useful tool to consider various string spacing distances on the fly! This way you can conserve valuable neurons and time for the more tedious work.

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