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 10 of 13 1 2 3 4 5 6 7 8 9 10 11 12 13
Write a review


By Amaury from France, Ardennes
(Customer's Reviews) Wednesday, May 11, 2011

Je suis trFs content de cet achat, je ne pourrait plus m'en passer c'est tellement simple et prTcis ta ne vaut pas le coup de s'en priver, ta permet de faire du travail de qualitT.

Necessary tool for beginners

By Clell from Dallas, TX
(Customer's Reviews) Saturday, May 07, 2011

Hard to imagine not using this tool in the past.

Time Saver

By JVan from Granger,IN
(Customer's Reviews) Friday, April 15, 2011

The first time I used it, I nailed it. My strings feel evenly spaced just the way the way they should.

A must have

By P.A. Roiron (Guitares-Roiron) from Lyon, France
(Customer's Reviews) Wednesday, April 06, 2011

Great time saver. Worth every dollar if you do repairs for a living.

Good for keeping existing spec

By P Smith from Cary, NC
(Customer's Reviews) Saturday, April 02, 2011

Experienced luthiers may scoff at using this tool as they can simply eyeball the spacing as well as anything the ruler may tell them. For those folks, perhaps this is not all that useful. However, for those of us learning or less experienced or if you have an existing instrument and you want to make sure the string spacing is exactly the same as the original nut, this can be a very useful tool to ensure you can capture exactly what the instrument had to begin with. Simply takes the guesswork out of the equation.

Not just for pros

By Demac from Seward, NE
(Customer's Reviews) Wednesday, March 23, 2011

I hesitated buying this tool, because I only work on my own instruments, and I just don't make very many nuts. (this was only my third) I tend to like my string spread as wide as possible though, and this tool made it so much easier; the last time I made a nut, after all the adjusting and correcting I ended up with the same spread I started with. This time, everything started out properly spaced, and no adjustments or corrections were needed. The ruler was designed for pros, but the occasional repairman (like me) can benefit from it even more, imho. I am giving this a four rather than five star rating only because it can be a bit of a handful to use, but I suppose that it gets easier the more you use it.

A must!

By J.C. Moranville from Colorado
(Customer's Reviews) Tuesday, March 22, 2011

No instrument shop should be without one of these scales! Very handy for 'floating' bridges as well as nuts. Hats off to StewMac. Buy an extra one and put it in a safe place.


By JonM from Ontario, Ca
(Customer's Reviews) Wednesday, March 09, 2011

After trying dozens of times to measure the spacing with a caliper i tried using the string spacing rule, first time i got perfect spacing. Will use this every time i make a new nut!

guitar upgrade

By robin ellis from shrewsbury shropshire england
(Customer's Reviews) Saturday, February 26, 2011

your service is superb, your tools are first rate. thank you stewart macdonald

It is as good as everyone says

By Utahraptor from Sandy, UT
(Customer's Reviews) Wednesday, February 02, 2011

It vastly improved the playability of a 12 string to get the string spacing correct. Super simple to use. Worth the money even if you only do one nut, but you'll want to make new nuts for all your instruments after doing the first.

Displaying 10 of 13
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