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 1 of 13 1 2 3 4 5 6 7 8 9 10 11 12 13
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Awesome tool

By Gianluca from Nottwil SUI
(Customer's Reviews) Wednesday, December 24, 2014

I'm a new be to the guitar building community and I have to say this is one of the most useful tools I ever bought :)

A bit expensive, but pays for it self every use

By Julius Jahn from Musquodoboit Harbour, NS  CAN
(Customer's Reviews) Saturday, August 30, 2014

You can get away with some calipers and the excel spreadsheet that does this for you, but nothing beats the convenience of being able to just scribe your lines, and start slotting. Used it twice, and it'll pay itself off very quickly.

Must have ruler

By b1ackstallion from Denmark
(Customer's Reviews) Tuesday, August 19, 2014

First of I think the ruler is a little expensive. However, now I have used it for 4-5 nuts following the instructions giving (1/8" from string to the edge). The result is better playability and even better sound. So the overall value is a more, but still :-/)

Extending the scale span.

By Alan 77427 from Kahibah, Australia
(Customer's Reviews) Monday, June 09, 2014

It's one of those tools that makes life easier and I wish that I had always owned one.
I was initially disappointed because I couldn't do my 41mm mandolin bridge spacing but then I realized I could go back to the treble end of the scale and skip every second slot thus increasing the overall string spacing.

Replaced my calculator and caliper

By geolang from Albuquerque
(Customer's Reviews) Saturday, May 24, 2014

This tool makes nut-slot spacing quick and easy. Previously, I was measuring from inside string to outside string and then using the calculator to divide the string spacing for equal string spacing. This method can be a bit clumsy as far as marking the slots on the nut for cutting. Even though equal spacing makes more sense to me (since the fingers target the middle of the string), I've found that the proportional spacing of this rule works very well. The difference between equal and proportional spacing is negligible in my book. Of course, this is a matter of personal preference, so unless you or your customer absolutely have to have evenly spaced nut slots I highly recommend this tool.

Fine Time Saving Tool

By Buzz Roberts from Crystal Beach, ON
(Customer's Reviews) Thursday, May 08, 2014

Takes the stress out of laying out string spacing and works as advertised. Well made and should last a lifetime.

this thing ruleZ

By sinvelikogmajstora from Cetinje, Montenegro
(Customer's Reviews) Monday, March 31, 2014

Real time saver, great quality, very precise, flexible, easy to use, perfect for any spacing on guitar or bass. Perfect results every time!

String spacing tool

By JMW from Biggleswade, UK
(Customer's Reviews) Monday, March 31, 2014

This tool saves me a lot of time on nut replacement jobs. It's a good quality accurate tool. Like another reviewer has already mentioned, I also have a piece of tape along the middle to allow me to mark which slots I need to use.

String Spacing Rule

By Martin from Rosario, Santa Fe, Argentina
(Customer's Reviews) Sunday, March 23, 2014

It is an excellent product and very well thought out. Making nuts is extremely easy with this tool

I love it... mostly

By Chellee Guitars from Orange City, FL
(Customer's Reviews) Friday, March 21, 2014

I have had one of these for years now and use it all the time. It is one of the few tools I own that has saved me tons of time and improved my life tremendously. I do have one complaint though -- occasionally I run across a guitar that needs a new nut with a very narrow spacing (usually because the fret ends are rounded off too much) and the spacing required is too narrow to measure with this tool. I would suggest that the next version of this was long enough to add enough slots on the wide end to fill the gap between using every other slot on the narrow end and using adjacent slots on the wide end. There is a range that exists in the real world that this tool currently doesn't cover.

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