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Hi All

I would like to know what nut action height you are using at the 1st fret. I am using a Stew-Mac nut action gauge. My normal 12th fret action is 7/64" at the low E and 5/64" at the high E. I usually set the nut action for the low E near 0.018" and then go steadily down from there to about 0.012" at the low E. Would like to know what you are doing. Thanks - Mike G

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guitarsbygiltzow.com

there are a few ways to do this. Do not rely on the free state of the string as the neck relief and action height can affect this. I use a straight edge that has a .007 notch ground in it. I want the nut slot about .007 off the fret plane and then the straight edge will butt on the nut so I know the slot is set.
You can also check it with the string , if fretted on the 3rd fret , the string touches the 2nd fret , just clears the first fret and into the nut slot. Having done 1000s of nuts over my career the experience helps. My best advice is to learn how to measure these small gaps. You can find good pin gauges that can help

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Michael - there are no hard and fast rules for setting action at the nut, but in general it must be fairly low for easy fingering and for correct intonation. Sounds like you are pretty close. Get a feeler gage set to double check your measurements. For ultra low action for my clients who are absolute spooks, I can get the treble E down to .005 between the bottom of the string and the top of the first fret. Bass E at least twice that.

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"Act your age, not your shoe size" - Prince

I don’t use feeler gauges just file the nut slots down till the string just barely is off the first fret when you fret the second fret. It’s not rocket surgery


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there are many ways to do a set up and you do have to know and understand what happens at the nut slot in relation to the fret plane. The best I can tell anyone is to take a trim piece off the 1st string ( .012) . The clearance off the 1st fret and the string when plucked , you can loop this under the string and fret , and lower the nut slot till this touches.
The gets you a clearance off the fret with the moving string , now you now can go down that far till it hits, I usually end up at about .007. Then you have to know that the steel string isn't bending on a given point so think roller not ramp so the string arcs out of the nut slot. It may take you a few tries to master this but it well worth the effort.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I think Mr. Hall offers an important insight, setting up a guitar isn't about the rulers, it's about the strings. Be patient, start high, work down slowly and recognize when you're done. And plan on spending hours on one nut on one guitar the first time it's done. S-M seems to imply that if we buy their tools we become experts, but there's no substitutes for experience and patience and insights. Can't buy that out of a catalog. It's gonna take a while.

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Peter Havriluk

Assume you've left enough room at the 12th to avoid dropping action below the desired numbers. With a player that is not too aggressive and an acoustic strung with light or medium strings, decent fretwork (although not perfect), a good place to start is 18/16/14/12/10/10...I can usually adjust that down a bit once I see where things are going.

The drill I did after I was 'allowed' to touch tools at Greenridge:

- Using eBay-grade nut blanks, mill up two blanks and fit to a specific guitar (we had a Greenridge OM and a 0000, plus a Morelli Tele and Strat, and a no-name 1980's 335 clone available).

- Once the blanks are fitted, mark and slot

- Set initial depth and slot geometry (see above for acoustic), tune up and play the instrument (address any artifacts which pop up, such as bad slot geometry, noting Mr. Hall's suggestion on natural curve with just enough angle at the front of the nut to firmly stop the string is a good one). Use a dial gauge and check with distance off the first fret when fretting second...over time, it trains the eye and hand, and makes checks with the dial gauge a backup to the visual check.

- Final-shape and polish, then restring/tune

- Drop the height by .002 in each slot and play instrument - this will usually not result in issues unless the fretwork or other setup work is iffy...some strings might be edging towards too low for aggressive play

- Take each slot down in .001 increments until the beginning of a buzz on that string.

- Use the extra blank to repeat the process, but stop short of buzzes.

- Do the same drill for a different acoustic the following day, then work through Strat/Tele and Gibson-style nuts over the next few weeks.

The idea of the drill was to begin to get a feel for what is high, what is good (for the guitar and player combo), what is close to too low, and definitely too low. It was also a good bit of training in being able to let go of a nearly-completed nut that was just not going to be good enough for a customer instrument. Tough to toss 3-4 hours of meticulous labor the first time, but knowing when to let go is as important in guitar repair as it is elsewhere in life.

The drill was not focused so much on completing the nut as it was on repeating the essential steps often enough to build the foundation for order-of-operations knowledge and QC skills. Even after making up at least a few nuts and saddles per week for over four years, I was still learning how to anticipate where further tweaks might better support the customer, or where extra clearance at the nut was needed in anticipation of slot wear due to hyper-aggressive playing styles.

Just before I departed my appenticeship, we got a 1972 Strat in that had been repaired by a gentleman that had apparently just hung out his shingle in the Vienna, VA area. After setting the nut action such that the guitar was unplayable open (per the owner), that gentleman elected to address the issue by level/crown/polishing the original frets. When we received the guitar, the frets were an average of 0.017" tall and the thick poly finish common to that marque was chipped out and damaged by the process crown process. A call to the repair person established that he could not get the nut out of the slot, so did a 'free' LCP. $600 later, the owner had a new nut, a touched-up/refretted neck, and a very playable guitar. Including the non-refunded charge for mangling his Strat, the owner paid over $700 for what should have been a 15-20 minute nut action tweak ($20-$35).

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For the times they are a changin'

- Bob Dylan

Nut slot height is a function of the specific string, the fret plane and to some degree the physics of the alloy and it's penchant for bending over the break point and the mass of the specific string.

Or, in other words cut them as low as possible with no open string buzzing with the truss rod set correctly FIRST and you are in the ball park. Our nut slots are cut lower than any measuring device that we can afford... can measure. Or, in other words for the high e when fretted between the 2nd and 3rd and held and when pulsing the string over the 1st we want to hear that "tink" sound indicating that the string is not in contact with the first fret crown and we want the gap to be so small it's virtually imperceivable. Dave Collins likes to say that he is looking for the presence or absence of a "sliver of light."

Why? Because it will play like butter, difficult for some people things like an F bare chord are much easier and intonation issues from string stretch resulting from nut slots that are too high is very nearly eliminated. So too is the attraction and need for compensated nuts on steel strings.

Nut slot cutting is an art and when I was a builder only I did it so seldom, at the most was when I was building one instrument a month that it was hard to get good at it. These days those who follow my Facebook page and who can stand me and I can stand them know that I cut nut slots for around half a dozen guitars a business day for years now.

I do go too low at times and have to build the slot back up but we use light cured dental fillings, harder than bone and won't wear out like CA and dust so it's no biggie for us if we go too low.

Please hear me on this one folks perhaps the very most important thing you can do in setting up a guitar is the nut slots and cutting them properly. It's immediately noticeable, a lost art these days so the guitars that you encounter, nearly all of them from any manufacture will not have the slots cut low enough.

Lastly this is an old world art and specific measurements are virtually useless outside of the context of that specific instrument. It is a feel and experience thing that I would recommend that you hook-up with someone who does it very well and buy them a beer or two or better yet single malt scotch.

Came back to add something. The above description of what we do is for the high e on a steel string guitar. The B and other strings are cut slightly higher progressively as they also increase in mass.

For example my high e has an almost imperceivable gap over the first fret crown when fretted and held between the 2nd and 3rd. But my low e will have a noticeable gap also when fretted and held in the same manner. As the string's diameter and mass increase so do my gaps.

But again for the high e and even the B the gaps are too small to measure. Dave took a run at measuring one of his high e's and he came back at .0005" over the first fret crown. Now I can't see this with my 65 year old, next week eyes. He can though, for now. Whippersnappers.....

So again it's very much working on a specific instrument and fretting, holding, observing and daring to go lower or pulling from your experience and knowing that you can go lower. There is a feel and experience thing very much in play here and I would venture to say that cutting nut slots well requires more experience and practice than any other aspect of setting up an instrument.

It's also the most bang for the buck for your clients and immediately noticeable as a huge improvement.

Dave likes to say "if it does not buzz open it's not too low." Now this is also in the context of using quality bone nuts that are not going to wear down next week either.

Hesh,

I use your method above, taught in the class at your shop. I wanted to clarify though, since the SM nut slotting gauge was mentioned. The .0005 measurement you mention. That is the string height over the first when fretted between the 2nd and 3rd or that is the string height over the first when measured with a tool like the nut slotting gauge?

I just want to make sure no-one is trying for an impossible value because they are confused on what was actually measured by Dave.

Brad


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But I'm going to guess that you folks have a Caolaidhe (kay-lee) or three - a road musician that makes Johnny Cash's driving rhythm work seem a little tame and wimpy. We were adding at least a thou and a half (more on the B) to keep his nut/saddle on his main acoustics going through a summer tour season.

'Carpenters work to the nearest 1/16th, cabinetmakers to the nearest 1/64th, and luthiers to the nearest player/guitar.'

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For the times they are a changin'

- Bob Dylan

Great to hear you are using what we taught in our class Brad, good going. Yes it's the strings height, the gap from the high e string bottom to the first fret crown when fretting and holding between the 2nd and 3rd.

The .0005 we would not take to the bank, it could be less, Dave says it's less but it's too small a gap for us to reliably measure. There are variables too such as how hard one frets and holds between the 2nd and 3rd can make some very stiff strings arc more or less.

By the way the day I met Dave I took a recently finished build to his shop and met him. As we exchanged pleasantries he opened the case, took the guitar and put it on his bench. I jsut went along with the program thinking this will be interesting. He proceeded to cut my nut slots and then sat down and played the guitar, looked up and me and said "nice." I was grinning like the idiot that I am and that's how it all started, Dave and my friendship and professional association, over my nut slots

When I played the guitar when he handed it back to me it was a huge improvement and now it played like those "old friend" guitars that some of us have been fortunate enough to have in our lives at times.

Yes indeed there are exceptions and we do have clients like you describe. We have had to raise nut slots for slack tunings and very light, extra light strings that have less stiffness and would make contact with the first fret crown. It is very much an individual thing with each guitar, player and type of strings.

The players keep us on our toes and learning stuff every day for sure.

In theory the nut slots should be the exact same height off the fretboard wood as the crown of the first fret is. In practice you can go a bit lower then that since the strings actually bend up into the air a bit as they ramp up from the tuner post through the slanted back nut slot. If the player likes slack key or they like to bang on the open chords then adjust as necessary. Mine end up being the way Hesh describes it. Really low on the e and b strings, almost imperceivable, then ramping up to the low E string. I don't measure either as it's beyond the range of any human use measuring devices.

Same same.


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Steve Smith
"Music is what feelings sound like"

Excellent and I'm very glad to read this and hear that it works well for you too JF. This brings up a related subject and that is how we can take a nut slot that may be a tad, a tad... too low and increase/restore that gap slightly over the first fret.

As you rightfully described strings arc a bit out of the nut slot face and that's why the nut slot can be lower than the fret plane crowns. We can increase this arc a bit by back filing the nut slot to increase the break angle a tad and then rely on the stiffness of the string to arc a bit more.

Additionally we can also add additional winds to the tuner post even wrapping a string down to the headstock face and that will increase break angle as well. These things in combination can take some nut slots that are a hair low and make them good again. Or simply raise it with a reliable, durable method such as light cured dental fillings.

For those of us who do Fenders all day long we all know the story of Leo and how he excelled in manufacturability but kind of sucked at understanding some of the physics of how a guitar works. One example of a shortcoming is the Fender neck. No head stock set-back angle and Leo's desire to use a readily available size of neck blank makes the break angle for his nuts too shallow.

Fender repair folks know our little trick to get around this. The shallow break angle on Fender's is the worse for the G so when I restring a Fender I wrap a good 6" of extra string onto the tuner post to increase that break angle. Modern Fenders have short tuner posts on the G to force this break angle increase without the need for that 6" of extra strings winds. Or a second string tree that you see on some Fenders, this is to increase the break angle mostly for the G and the D to some extent.

Those heavy handed players that Woodie rightly brought up benefit from Luthiers who understand the Fender G string nut slot shortcoming and who know how to address it since they can hit a string hard enough for the vibrating wave of the string to breach the shallow nut slot and buzz.

Who know that a simple nut slot has all of this to talk about including much more such as the angles to cut, rolling the back side as Somogyi does and much more.

Again nut slot cutting is an art and a learned skill that takes lots of practice. Dave Collins told me that at the Galloup school they will tell you that it can take 100 nuts before a student is capable of making a good nut.... Dave used to teach there.

I enjoy nut making and like working with files and fine work like this. I am always reminded of the sailors of old doing their scrimshaw when I make a nut. I'm not very fast at it but it's a good, relaxing time to sit back and hand craft a minimalistic, eloquent nut that follows the lines of the instrument, fits perfectly with no gaps and down everywhere and is buffed out to a high polish that may even look like plastic it's so shiny.

String spacing and edge gaps are also related and important as well and there is the subject of bone, processing it, using cattle that free range and do yoga and the advantages of same too. Lots of related stuff to discuss.

Well put. Being a reasonably accomplished player of some sort, helps to intimately understand that setups are as much about the player as the physics. The lowest action without buzzing is not the answer. If one does enough setups for enough accomplished players in enough different types of guitars and genres, this becomes evidently clear.

That said, there are some standard numbers one can work toward. Process can help or hinder. Building instruments is tough because one just can not get the experience required. Build one guitar, perform one setup. This is where repair work pays off - where else does one get to do thousands of setups and interact with the people that wish to leverage those setups.

I never measure first fret action.
The nut should be set very close to the fret plane, as others have correctly stated. If you do that, the first fret action will always be close to 11.2% of the 12th fret action (assuming a straight neck). This is simple geometry.
The goal of any setup should be to make the tendency to buzz the same thoughout, including on open strings.
1) If the nut is higher than the fret plane, then the tendency to buzz on open strings will be less than on fretted strings. Also, the intonation will suffer, and the guitar will be unnecessarily harder to play in the first position.
2) If the nut is lower than the fret plane, then the open strings will buzz more than fretted notes.

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John

having built for over 20 years I have learned a few things. Years ago CF Martin gave me a nut gauge that they use and I found it very helpful. I hope John A pipes it

this gauge was a simple piece of .009 feeler gauge. On this there is a .007 notch ground in it. It works by riding the frets
and the notch is to clear the bottom of the nut slot and the edge of the notch hits the nut . Using this I have been able to get very good nut set up.
I do use it with string tension to do the final fit. You can attain a good nut to 1st fret clearance. We all strive to get that perfect set up and this helps to be consistent .

I like john don't really measure action on the first fret , and the better you can get your set up the better the guitar plays, the less intonation issues and if a guitar plays well you customer will be much happier.

You can get pin gauges to actually measure the clearances off all the strings and it is a good exercise to train your eye to see that relationship. If you can slip a.009 string under a plucked string and just have it glance off you will have a great nut set up and this makes the guitar feel soft to play.

I am happy so many are sharing their info

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it