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
In stock, ready to ship!


Total: $0.00
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 8 of 13 1 2 3 4 5 6 7 8 9 10 11 12 13
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By p gaudreau from canada
(Customer's Reviews) Friday, November 18, 2011



By william hill from england
(Customer's Reviews) Wednesday, November 09, 2011

With the stewmac string spacing rule, you have peace of mind that the guesswork has been removed. A guitar nut has multiple vital tasks to perform so this must be accurate, kit as cool as this is absolutely necessary, i was pleasantly surprised at how close my own measurements were to the perfect spacing, but i feel confident now that a miss is as good as a mile,this rule is a direct hit. Now i dont have to shoot in the dark, when something is not right ,,,its wrong, this rule is right as rain. This photograph shows the slight innaccuracy in my old item, and the replacement compensated nut ready for cutting and fitting to my '79 strat.

Spaced correctly

By tb from Portland OR
(Customer's Reviews) Friday, October 21, 2011

If you don't purchase pre-slotted nuts this tool takes the guesswork out of spacing string slots correctly. I've cut a few nuts and used this to space the inner 4 strings properly after laying out the two E strings to where I want them. If you've been doing this for years your experience may be a great guide. For those of us maintaining our own gear this takes out some of the guesswork.

you gotta have this

By sherman stockton from indiana
(Customer's Reviews) Saturday, October 01, 2011

makes nut spacing fast and easy

Time saver

By Mike T. from North Carolina, USA
(Customer's Reviews) Thursday, September 15, 2011

This is 100% faster than the old way. Nothing wrong with the old way, but time is money.

Mando Purchase

By Eric from Englewood, OH 
(Customer's Reviews) Monday, August 29, 2011

It takes a little time and thought but once you figure it out your string spacing will be correct.

Nut spacing made easy

By Old Town Gutiars from Georgetown, TX
(Customer's Reviews) Sunday, August 28, 2011

This has taken my nut making to the next level, and has helped speed up the job. I was unsure if it would be worth the investment, but I now can't imagine making a nut without it.

string spacing rule

By Rob the luthier from Scotland
(Customer's Reviews) Friday, August 19, 2011

this is a must have item for your lutherie toolkit, takes the guess work out of string spacing, every luthier should have one...

String Spacing Rule

By JMAN from Australia
(Customer's Reviews) Wednesday, August 10, 2011

This was my first purchase from StewMac. I attempted to slot a nut only once in my life and it was a shocker. I then received the string spacing rule and followed the instructions it was sent with. The nut turned out perfect in regards to spacing and playability. This rule is probably the best thing since sliced bread. Too easy to use. Expensive for what it is BUT it makes the job so much easier and saves time too. However, it's only going to give you correct spacing that feels great, but the rest of it is up to how you actually slot the nut. That's an art. Best buy ever for me.

Awesome tool to get spacing just right

By joeyl from El Paso TX
(Customer's Reviews) Wednesday, August 10, 2011

It is a quick and easy method to get nicely spaced nut slots. After seeing the results, all my previous nut jobs look off... Takes a few minutes to get the hang of it, after that, it becomes super easy to locate the right marks.

Displaying 8 of 13
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