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 3 of 13 1 2 3 4 5 6 7 8 9 10 11 12 13
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Time saver.

By Garry Petrisic from Toronto NSW Australia
(Customer's Reviews) Wednesday, October 23, 2013

A great item. I used to do all nut widths sizes and it took time to get right. Takes the brain work out of the equation. Should have had one years ago.

Should have bought sooner!

By WBR Guitars from USA
(Customer's Reviews) Sunday, October 13, 2013

It takes a little practice to get used to it, but worth the learning curve. I went through my 4 guitars, bass, and ukulele. Found 1 acoustic that is a little off with the nut spacing. It now makes sense that I tend to make more "mistakes" when playing this guitar versus the others. This will be part of my set up tools from now on. Forget the internet "printouts", get this tool for true precision.

I love this tool

By All-Strings Instrument Service from IL
(Customer's Reviews) Monday, September 09, 2013

I use it for string spacing all over the place. Awesome tool that takes any guess work out and speeds up the job. BUY IT!

Great Rule

By Steve C. from KS.
(Customer's Reviews) Monday, September 02, 2013

This is great tool and absolutely essential. From nuts to tune-o-matics, this makes short and accurate work of string spacing. Get one!!


By Dave Ward from Oklahoma City, OK
(Customer's Reviews) Tuesday, August 06, 2013

The String Spacing Ruler makes fabricating nuts from blanks quick and easy with professional results. The tool paid for itself the first time I used it!

spaced out !

By ron hyde from wa.
(Customer's Reviews) Friday, July 05, 2013

I've been luthierin for 50 years and slowly loosin focus , critical measurements are easy with this cool tool!

String Spacing Rule

By Dennis Walsh from Massachusetts
(Customer's Reviews) Thursday, June 27, 2013

This is a great tool if you are cutting nuts from blanks. This is especially true on a bass where even spacing makes the low strings feel crowded if not deferentially spaced. Don't know why I didn't buy it years ago. I used to "figure out" the differential spacing, now it's a snap.

no brainer

By Milagra Dulce' Guitar works from Oregon
(Customer's Reviews) Wednesday, June 05, 2013

I make everything! I shape the body and neck, I build the bridge and of course the nut...everything. this little ruler saves time!! Guitars, basses, whatever your making you set it on it gives you the perfect spacing every time.

Mess up proof.

By Penitentiary Hollow Stringed Instru from Attalla, AL
(Customer's Reviews) Friday, May 31, 2013

This makes marking the nut less cumbersome. This int cumbersome at all really. It sucks when your ruler moves. Of course this results in better accuracy, and faster completion of the job.Time is money.

Convienient tool to have in your kit

By Patterson from Fremont, MI
(Customer's Reviews) Wednesday, April 03, 2013

I always just spaced strings using a standard steel rule. On a whim I bought this gauge and am glad I did. Makes accurate string spacing on nuts and bridges so much faster and easier.

Displaying 3 of 13
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