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 6 of 13 1 2 3 4 5 6 7 8 9 10 11 12 13
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Utterly Irreplaceable

By Seth Naugler from Bucks County, Pennsylvania
(Customer's Reviews) Thursday, July 05, 2012

If I didn't have this thing I think I'd get out of the business. I've swiped a lot of ideas from Kevin Ryan, probably the most brilliant developer of jigs and tools in the business, over the years and this is one of my favorite. Unbelievably simple and clever.


By DAB Custom Guitars from Pa
(Customer's Reviews) Saturday, June 23, 2012

This is a must for cutting new nuts, it is well thought out and made well. Really can't say anything bad about it at all, the only way I've gotten professional results is with this tool, thanx Stewmac!!

A Real Life Saver!

By Bill Badeaux from La Porte, Texas
(Customer's Reviews) Wednesday, June 20, 2012

I don't know how I ever lived without this wonderful little rule. My long-time friend and mentor Dave Nichols of Custom Pearl Inlay told me about it and that I should not make the nut for my latest guitar without it. So I ordered one, used it for my string spacing, and... Perfect! Bill Badeaux, Badeaux Guitars

Best Tool.I love it.

By okokguitar from Songkhla Thailand
(Customer's Reviews) Friday, May 18, 2012

Best Tool.I love it.

Must have tool!

By DJAcoustics from Michigan
(Customer's Reviews) Tuesday, May 01, 2012

Use with a scribe & your nut slot accuracy cant get any better!

String spacer

By J. Wiseman from USA
(Customer's Reviews) Saturday, April 14, 2012

This thing sure puts strings in there place.Much faster than the old way.Well worth the money.


By Dingobass from Perth, Australia
(Customer's Reviews) Wednesday, April 04, 2012

This is the best tool yet. Takes all the guesswork out of making your own nuts. Simply brilliant.

Pretty cool

By Jerhico Guitars from Altona, NY
(Customer's Reviews) Thursday, March 29, 2012

Havent used this a ton yet. Still using my 6 inch rule. Assuming that all of the marks work as they should this is a great tool. The couple times I've used it, it has worked out perfect. Just that old habits die hard and I just automatically grab my steel rule to do my string spacing. When Im nearly done is when I remember this tool.


Why did I wait so long?

By Bill Styler from Priest River, ID
(Customer's Reviews) Thursday, March 22, 2012

I kept putting off getting the string spacing rule. Now my backside is a bit sore from kicking myself - indispensable - nuts are laid out in a flash. One of the best products I've used in guitar building and repair.


By Bjarne Bayard from Denmark
(Customer's Reviews) Friday, March 16, 2012

All the time i¦ve spent measuring string position........
How did i do without this,blilliant tool

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