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Does anyone have any tips on slotting nuts? I have a set of nut files and feeler gauges and I just file each slot and keep on testing string clearance above the first fret with the feeler gauges. Trouble is, I can't seem to cut six slots without going too low on at least one. Then I'm in to filling the low slot with bone dust and making it solid with CA so I can do that slot again. This works but it bugs me that I can't seem to make a "clean" nut. Do any of you have any techniques that prevent you from going too low when you file your nut slots?

Thanks,
Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

The best technique to keep from going too low is to make a few dozen dozen nuts.

The best shortcut to being able to make perfect nuts is just lots and lots of experience (which unfortunately isn't a very short shortcut ).

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Eschew obfuscation, espouse elucidation.

Pat, that's a timely question you ask. Very recently, I have just fabricated what I feel is my best nut to date. For me, what made the big difference is using those mint set of nut files from Stew-Mac. It's a no brainer. The file is exactly (or very close to) the size of the string.

But first, I guess one should define what makes a perfect nut. To me, the nut slots should be as close to the exact half of the string profile. Consequently, the bone should never be higher than half the height of the string. The bottom of the string slot should never fall bellow a line drawn with a very sharp half-pencil laid flat across as many frets as the length of the pencil will permit... We'll all agree that in the case of the small "e", this makes for a very minimal channel indeed!

I always try to stay just a touch shy of the pencil line. You can always loosen the tension in the string and dig deeper at your discretion.

I use a very nice Excel program that AZ (Anthony Z, A.K.A. Herr Zlahtic) sent me to measure out the spacing between the strings. If you want to give it a go, just send me your e-mail address and I'll forward all 18 kb's of it to you... It's as simple as can be. Enter the dimensions you have and what sized strings you intend to use and the program gives you all the measurements you need.

I like to use milimeters. I find a tenth of a 'mm' is much easier to locate than a nasty odd-numbered 64th!

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I'd like to be able to prove, just for once, that money wouldn't make me happy...

I stack up 2 layers of aluminum tape and stick it across the first fret and then add a third layer under strings E,A,D&G and file the nut slot down until the string just touches the tape. I do this tuned to pitch except the string I'm working on, which is slightly detuned, enough to get it out of the slot. I then finish profiling the top of the nut to the proper height.
They're are many ways to do this and I'm probably the odd man out here, but it worrks very well for me.

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Jim Watts
http://jameswattsguitars.com

On the last several guitars I have been spending a lot of time on my nuts......

This is what I do. First I am sure to cut the nut slots at 1/2 of the difference between the plane of the fret board and the tilt back of the head stock (15 degrees). So this means that when you are using the files you want to be cutting at something like 6 - 8 degrees back from the plane of the fret board. Also be sure to have the slot on the face of the nut be the highest point and have a clean drop off down the face of the nut.

Although I have feeler gages and the Stew-Mac set-up gage I don't like using them at all.

Understand in advance, and this may be why you are having problems, that cutting the nut is a dynamic activity. You can cut one slot pretty close, add the other strings, tension them, neck relief sets in, and low and behold a slot may be to low now. Sound familiar?

What I do now is this: I cut each slot to high and wait until the entire guitar is strung up and tuned to concert pitch. then one by one, taking no more then three swipes of the file at a time, I lower each slot and then stop, retune, and play the sucker. Yep, I am doing this by feel alone.

On this second pass I am trying to get close but not necessarily as low as I can go. I repeat for each string, cut, retune, play.

After the second pass it is close and I tune it to pitch and play it for a while being sure to press the strings right next to the nut firmly down in case they are not seated and the slot is actually deeper already.

Leaving it under concert pitch tension until the next day I revisit it, again taking no more then 2 swipes at once with the file, I further reduce the nut slots until the guitar plays perfectly.

This seems to work great for me and I hope that it helps you too.

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Ann Arbor Guitars

Like any precision hand work, it's all about feel and there is no teacher better than focused practice. Each set of files cuts differently, each angle of attack feels different, each nut will feel different, each stroke will produce a different little pile of bone dust at the base of the cut which can give a good visual clue as to what's going on.

If you go too far on one slot, instead of filling in that single slot I would suggest you try adding a slice of ebony or bone as a shim under the nut - bringing all the slots up higher than they need to be - then bring all the slots down again. Even better: before you add the shim to try again, use the opportunity to bring each slot down to just where its string will buzz to teach yourself when you are about to go too far (If you don't know how far is too far, you'll be more afraid to go too far and your slots will stay higher than they need be). Then add the shim and get it right or add another shim and repeat...

I recently posted on setting nut height on another forum, and since I'm too lazy to type it again I'm just going to copy and paste my posts from there to here. The topic is close, but if there are points that don't apply to your case in particular forgive me - it may have been originally written for a slightly different audience. Here it is ---

- Adjusting the height is such a hard thing to communicate without being able to point at the right height in person and say "make it just like this". There just aren't any tools readily available to reliably quantify the measurement. It's one of those things that when you know, you know, but learning what you're looking for and even how to look at it can be the hard part. It can be difficult to know when you've got it right without at least having someone more experienced to revue your work. Many people have learned on their own, but it generally takes a while.

Measuring is so difficult because it pretty much has to be done by eye. I strongly dislike the idea of measuring the height above the first fret with the string wide open, as in doing that you are including so many other variables that will make the measurements crude at best, and often quite misleading if something else is out of adjustment. Fretting the string past the second and checking clearance above the first is more the reliable standard method, but the distance traditionally has to be checked by eye, and describing the distance without seeing it can often be a challenge. Trying to use a feeler gauge under a string is not very reliable, as it's hard not to disturb a string out of position as you're trying to slip a .001" feeler gauge under it. I'm not saying it's quantum mechanics, but it is a case where the act of measuring will often affect a change greater than the tolerances you aim to hold in what you are trying to measure.

For teaching and demonstration purposes I made a some gauges a while back to try to quantify and better communicate accurate measurements. The first one I made measures the clearance above the 1st fret when referencing from the nut to 2nd fret, or the measurement you are usually viewing. The second version references off the first 2-3 frets and measures the height of the slot above the plane of the frets. This one is more sensitive, as the geometry of it will make it register almost 2x the distance that the first one does. Of course these measurements rely on the frets being perfectly level, and to some degree to the neck being adjusted straight.



One measures below the nut-2nd fret plane, so reads negative when the string is high. The other measures the nut slot above the fret plane, reading positive. In this photo the top row demonstrates a nut I would consider very high, middle row shows an ideal height (for this particular instrument anyway), and the bottom showing a slot far too low.



On the average Strat or LP I will generally end up with the high E in the .001" to even <.0005" range, and the low E in the .001" to .002" (I'm referring to height of slot above fret plane, or the gauge on the right). It all depends on the player and the individual instrument of course though. A heavy flat picker's D-28 may end up at .002" and >.003", and of course rules are different for classicals, banjos, etc.

I know Don at StewMac was working on a similar tool as of maybe 6 months or so ago, so there's a possibility something similar will be available on the market some time soon, though I really don't know. In any case, it's not a tool I would advocate for full time use, but would be great for learning, teaching, and documenting. Relying on it too much would be a crutch in my opinion, and there's no replacement for learning how to look and gauge by eye.

I don't know if any of this helps at all in your particular case - this is one small factor. Doesn't touch on spacing, backfiled angle, tool choices, fitting and shaping, etc. Perhaps it will help you understand goals and perspective on tolerances though, how to reference height, and what to be looking for. -


-Now the "half-in, half-out" thing gets brought up quite often, but I always stress to people that it is only an aesthetic and doesn't serve any real functional purpose. It certainly speaks of fine craftsmanship, which is why I typically aim for something similar (though I typically aim for only 1/4 to 1/3 exposed. The string itself is oblivious to anything above it's midpoint, making the material above irrelevant in most cases - could be a quarter inch above the string and it would still work the same.

The exception to the rule of course is if the break over angle is shallow, in which case the string should never be more than 1/3 exposed. Go to half exposed and many players would be popping strings out of the nut with bends and pull-offs. String trees obviously help this on a Fender. Since it's only an aesthetic I personally prefer to leave no more that 1/3 exposed as a general rule. -

----


Sorry if those posts seem a bit disconnected, but they're pieced together from another discussion. Perhaps it can offer some insight to goals though. Some other notes not mentioned above - I never loosen strings while cutting a slot. Just lift it out (I use a little brass hook I made), take a few passes with a file, pop it back in and check it. Many people use the half-pencil line trick (including myself) to rough in the height, but it is only really useful for roughing it in. Even a fine .010" pencil line is about 10x the width of the tolerances I aim to hold.

And again, that gauge idea was just for a method to accurately communicate and document height. I don't personally use them when making a nut, but they could be useful for people learning without a mentor for hands-on critique. If Stew Mac or someone can make them for a reasonable price they could be a useful training tool. Still, it's all just going to come down to practice.

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Eschew obfuscation, espouse elucidation.

Excellent post David - thanks!!!!

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Ann Arbor Guitars

Agreed David...thank you greatly.

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Eagles may soar, but weasels don't get sucked into jet engines.

Here is my two cents…Take a pencil and grind it in half lengthwise. After you fit the nut to the neck, lay the pencil on the last couple of frets and make a line on your nut all the way across. Now you have a reference line on the nut. My preference is to have the low E about .030” above the line and the high E .010” over the line (I eyeball the heights above the pencil marks). Then the other string slots match the radius of the fingerboard using the E string slots as your reference points.
Anything above the line is fine and is a mater of personal preference. If you go below the line you have gone too far.

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Rich S

"The inconvenience of poor quality will linger long after the thrill of a bargain has been forgotten"

Pretty basic but I stick with an old, uncomplicated, tried and proven method. I rough cut in so the slots are a little too high and then tune to pitch. I run a straightedge between the strings across the top of the first couple of frets. Then using a feeler gauge between the surface of the fretboard, the nut side of the first fret and the underside of the straightedge, I CAREFULLY measure the height of the wire at the first fret.

That height now determined, I add a feeler blade to represent the desired clearance I'm looking for between the bottom of the string and the top of the first fret. I place the combine feeler blade stack or it's equivalent eg; maybe .032 for the wire + .008 for the desired clearance = .040 hard down onto the surface of the fretboard and firmly against the front face of the nut. I take the appropriate slotting file and file the slot down until the file makes clean contact with the top surface of the feeler blade stack.

Cheers

Kim

Thanks for all the replies guys. I've got a few ideas to try.

Pat

_________________
There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

A big step forward for me was that little string lifter Stew Mac has. You could make one easily. You can get your slots in the ballpark and fine tune easily with the guitar at tension without a lot of tuning and re-tuning. I also use it to lift the strings when intonating the saddle.
I've learned to go few thousands shy of the final depth and let it sit for a day or so and re-tune once or twice. Then do the final tweak. Seems like the strings sometimes settle in just a bit from where you left them with the file.
Terry

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It's not what you don't know that hurts you, it's what you do know that's wrong.

I once ruined 3 nuts before finally getting it perfect on a customers guitar. Ruined guitar nuts can make good uke, mando or banjo nuts sometimes.

I got me one of them string lift'in thing ma jigs from stew maccy too and I reckon it's grouse

Cheers

Kim

One of, if not the single most used tool in my shop is my string hook. I was never attracted to StewMac's version for a few reasons, main one being that it's just too wide. For a person who works on a lot of mandolins and twelve strings, it would just be too cumbersome. I also prefer to be a bit more free to simply lift the string directly upward and move it where I like.







It's just a piece of brass (1/16" I think) with a hook bent and filed a bit in the end, then folded double for the handle. Simple to make and easy to use. It doesn't take near enough force to lift for me to justify any kind of cam system, plus I can use it on a mandolin. The only time I ever have to loosen a string is on the outer strings of the occasional slotted peghead guitar, or some lap steels and square necks with 3/4" tall nuts.

And though I'm sure there are many methods and tools people use to gauge height, I've never found anything as convenient or accurate as simply using the string as a straight edge by fretting past the 2nd fret. If you adjust your bench lamp it's easy to see the shadow or reflection in the fret, and it's the movement of that reflection as well as the sound and feel as you tap the string down on the first fret that can give you more precise measurement than any measuring device I've found. It just takes a bit of experience to learn exactly what movement to aim for. Do it a while and you develop a simple rhythm of fret, tap, lift, file, return, fret, tap, lift, file......

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Eschew obfuscation, espouse elucidation.

Way too simple David. I love it!
Terry

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It's not what you don't know that hurts you, it's what you do know that's wrong.

The old half pencil line here...it works!

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JJ
Napa, CA
http://www.DonohueGuitars.com

I see David using tools like his very fine string lifter when I visit David but I don't feel like it is my place to divulge what I see anywhere I go unless I ask in advance. So I feel like Arnold Horshack when I read these threads and have some info about a very cool solution but can't say so.

It's "Oh, oh, Mr. Kotter, Mr. Kotter........."

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Ann Arbor Guitars

Hesh Breakstone, Gentleman , Scholar , Keeper of Secrets!

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

I use the half pencil trick to get the nut filed down to "working height", then I use feeler guages set directly against the saddle side of the nut and nut files to get the strings to the proper height. When you are filing, as soon as you ehar the file touch the feeler guage, STOP!!

It should be perfect from there, but I usualy add a few thousands to the feeler guage height just in case. I can always go back and shave those extra few thousands off if needed.

So far this method hasnt failed me.

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Reguards,

Ken H