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I always thought the discussions I've seen about nut slotting seem to make things much more complicated than they need be with things like the Stew Mac gauge, feeler gauges under strings, etc. I've also noticed that a large majority of repairs that have come through my shop could use a little nut work... I feel like getting nut slots the right depth is one of the most important things affecting playability yet time and again I see examples where there is a lot of room for improvement.

Anyway, I measure things with a very simple tool: a thin straight edge about 4" long... long enough to cover the first two or three frets and thin enough to fit inside each slot. First, check to see if the slots are too high... I want the slots to be exactly on the plane of the frets just like a zero fret would be. With the guitar at pitch, slide the rule up next to each string and have a look... it's usually pretty obvious if the slots are too high. This guitar's B string needs just a little tweak; it's close but could be better:


If it needs a deeper slot, loosen the string a few turns and slide it over to the next slot. File down a little with your favorite nut file, then place the rule in the slot and over the frets. If there is any daylight under the first fret you're not there yet. If it hurts your eyes to focus on such a tiny space, push down and pull the ruler back until it falls out of the slot... if it clicks that means it dropped down and hit the 1st fret meaning you're not there yet:


Repeat until you can slide the rule back in each slot without a click (or a very light one for folks who want a little extra nut action). I do this while the guitar is at tension otherwise depending on the neck, there may be some back bow which will mess up your fret plane making you go too deep. And if you do go too deep, cut a piece of paper in the shape of the nut's footprint and place it under the nut as needed. I've found that CA and bone dust stink as filler material.

I can usually tweak all six slots within 5-10 minutes and there's no math or complicated gauge/jig setups. I don't begrudge anyone their own slotting technique - there's a bazillion ways to do every task and whatever works for you is likely best for you - but I thought I would share what I think is a super simple and effective way to do this... I hope it helps!

That does seem like a simple, straight forward way to get the nut to a '0 Fret' status. I think I'll give it a try on my next build.

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Joe Beaver
Maker of Sawdust

Cool! That seems logical.

Thanks for the clever idea James!
This is going to save me a lot of time and guesswork.

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Wah-wah-wah-wah
Wah

That's much like I do it, James. I file on the head plane and roll onto the neck plane for the final stroke. Just gotta make sure your nut files have a straight edge...

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

I would think one's scale must have a round edge so that the center hits the bottom of the nut slot........???
Tom

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A person who has never made a mistake has never made anything!!!

If it's thin enough to fit in a .012" nut slot that's not a practical consideration IMO... I guess you could chamfer the edges easily enough if it bothered you.

James : Certainly don't have any .011" scales myself. My thinnest is about .040". One could use a long.011" feeler blade. I do have some of those. Thanks for the come back.
Tom

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A person who has never made a mistake has never made anything!!!

Pretty cool James, all this setup chat sure has me re-thinking the Bryan Kimsey .022" - 018" clearance at the first fret...

Just to be clear on what I wrote here, I use gauged nut files. So if your files have straight edges (fortunately, at least one edge is straight on all of mine), you don't need to use a rule as per James' method, as the file itself acts as a rule. Just file until when you drop the file onto fret two with it still in the nut slot, it juuussst clears fret one. Then you're done.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Yeah James you sure are right, the easiest, simplest way is certainly the best and then Trevors' one tool for the job doesn't really get any better. Great tips guys thanks.

Steve

I have straight slotting files myself. Brillant!!! Why didn't I think of that?

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Joe Beaver
Maker of Sawdust

Thanks for the tips, I'm coming to use them for sure.

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We are all in the gutter but some of us are looking at guitars.

Thanks James, good technique (if the edge in the slot is radiused when setting the nut action so low.)
I've used Norman's Nut Files for my first 5 (7 if you count failures), - essentially hardened feeler gauges, radiused each edge, with teeth cut on one side only.
Just turn from the cutting edge to the other side and check for clearance between 1st fret and the tool.
Also use the blank side to do basic smoothing/polishing on the bottom of the slot.
When they wear out (I'll try sharpening them first!), I'll be keeping them just for the nut action setting.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Well, I don't want to sound like a party pooper here, but I'm afraid I will...

I see three problems with this method.

First off, even if your rule is as thin as the smallest slot of the nut, it's side is flat (as opposed to round, as a string is), thus the point of contact between the slot and the rule is not the very bottom of the slot. So when "you can slide the rule back in each slot without a click", the bottom of the slot will be just a tad lower than the frets (which we don't want).

Also, there is a good reason why you want the slots to be just a bit higher than frets: to avoid backbuzz. When fretting a string, the back of the string (the portion that goes from the nut to your finger on the fretboard) may vibrate by resonnance, and you don't want that vibration to hit the frets. Having the nut slot just a bit higher than frets allows for that portion of the string to vibrate freely. This is the biggest drawback (that I know of) for having zero frets.

And thirdly, when setting up a nut slot height, you have to take into account the wear and tear the slot will endure over time by the string sliding in and out of the slot as you tune it (and consequently 'filing' it down a bit each time, specially with wound strings). A nut with the slots as low as the fret height will need to be shimmed sooner than later.

My 2 cents...

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Not yet , But I WILL ! Great Idea .

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Indeed; party poop away! it's a great way to get an idea challenged and refined. To your points:

Like I said above, for me it hasn't been a practical consideration, but chamfering or radiusing the bottom where it will need to ride in the nut slot seems a trivial thing to get around this.

This does seem like it could be a concern but I have never noticed it on my guitars and have never had a customer complain... maybe this is a bigger deal with nylon strings which make a bigger arc? I have never experienced it on my two classic guitars but I keep them with no neck relief... I can see how this could happen as you play up a fretboard with some relief. Maybe I have just never noticed it. Even so, it seems like a trade off between playability and a potential problem.

A solution might be to cut a small notch in the front few mm of the rule with as much nut relief as you would like to have like so:

Here if you wanted nut relief you would set the end of the rule in the nut slot to measure; if you wanted zero nut relief you would just move the ruler forward up to where the full depth would sit into the nut slot. I also should add that sliding the rule back and hearing the click is a tactile thing as well... As the slot goes deeper the click sounds and feels lighter; it's pretty easy to feel how close you are as you get close.

Again, another tradeoff: playability for longevity. I know I would take playability on my instruments any day of the week but I understand there are many who would not.

Many thanks, James plus everyone else for your sharing of methods, questions etc. I find this very helpful.

A question, though: James, do you use this method for classical or steel-string guitars, or both?

Thanks again,
Max

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Max Bishop
Brighton, Michigan

Hi Max, I use it for both, but the vast majority of guitars that come through my shop are steel string and electric, so that is where I am most comfortable... In short, I cannot recall any feedback from classical players on nut setups.

Hey James,

Hope you didn't take my comments as blunt attacks on your technique. That was not my intent. I was mainly trying to 'warn' you and others about potential issues with this method. I used to aim for the very same end result (no nut releif) until some of my guitars came back with the issues I mentioned. Then I started changing my ways a bit.

The notched and chambered rule idea pleases me though. I might steal that...

Cheers,

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

When you capo, arent you using a "regular" fret as a zero fret without a problem; why would the zero fret be any different?

Just like a zero fret, using a capo makes a guitar more prone to backbuzz. Backbuzz won't happen automatically, but it just increases the chances.

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Hi Alain, I didn't take it that way at all and appreciate your comments... listening to different perspectives and experiences allows us to grow as craftsmen and I am thankful you took the time to share yours

James,
I used a 4-mil thick feeler gauge and your technique.
Worked like a gem! No more squinting. I achieved insane zero-fret action on my new electric build.
Thanks for the clever idea!
I'm redoing three other guitars tomorrow before I box them up for X-mas presents.
Regards,
Dan

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Great! I'll be using it!