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Hello, I recently purchased stewmac's nut files as part of their guitar shop starter kit. I finally decided after too long of dreaming about pursuing this hobby it's time to $&@" or get off the pot. In reviewing stewmac's recommended procedure of stacking feeler gauges at the desired string height at the nut and then filing string depth into the nut, stopping when the file just nicks the feeler gauge stack. Makes sense to me other than I picture this to be much like cutting up a downed tree with a chain saw and hitting the dirt below as you cut through rapidly dulling your chain, or in this case the nut file. My instinks tell me "nicking" the feeler gauges are going to ruin the files much quicker than cutting into bone only. So my question to this group is what is the thoughts and experiences of those who have used these files? Thanks for taking the time to respond.

Nut files require a little more finesse than a chainsaw.
I use the nut slotting gauge from Stew Mac for final slot height. Works nice,
every time.
http://www.stewmac.com/Luthier_Tools/To ... Gauge.html
Ken

I'm with you David! The chain saw analogy is a good one. You can cut wood like butter all day but one touch to the dirt and it's time to break out the file. I'm not sure exactly how hard feeler gauges are but the last thing I want to do with a nice set of sharp files is start hitting spring steel with every slot.

I think that method is going to slow down learning anyway. It might get you close, but there is more to proper string height at the nut than just the height of the slot from the fingerboard. Angle of the slot, string gauge, shape of fingerboard end , etc.
Fretting lightly at the 3rd and looking at the clearance over the first takes those variables into account. Your going to have to get a feel for how much your taking off as you file at some point, you may as well get on with the learning. There is no practical measuring/stop system for the minute increments involved in nut filing.

One tip: any binding of the file in the slot is going to spoil the feedback you need to know whats happening. Make sure the slot above where the string sits is wide enough to let the file pass smoothly. Then you can feel it cutting on the slot floor.

I appreciate Stew Mac's efforts to make things easier for the beginner, but even without ever having tried the method, I can't see it working too well. But maybe someone who swears by it will chime in.

I tried stacking feeler gauges at the nut and didn't like it when my files cut into them. Instead I take a half pencil and make a "zero fret" line, file down close to it, then finesse the slots to the actual clearance that I want for each string





btw, I have used StewMac nut files on 20 guitars and countless setups - they were a good investment

I place a thin feeler gauge leaf in the nut slot and against the second fret.
You can clearly see the gap between the leaf and the first fret.
This distance coincides with the distance from the bottom of the installed string and the first fret when the string is fretted at fret two. You can get very close to a zero-fret slot depth this way.
A feeler gauge set is a lot cheaper at Walmart than SM.

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wah
Wah-wah-wah-wah
Wah

I use that method (the feeler gauge) to quickly get close and then refine if necessary fretting at the third fret. I think it works great. I use a stainless steel feeler gauge which is softer the the file which is all you care about.

Plus, if you are watching what you do, you just kiss the gauge with the file.

And..although bone cuts easily it might well be more abrasive that the gauge is to the file,
Mike

I don't stack feeler gages under the file either. I slowly work my way down. Make sure you buy a stack of nut blanks for the first several guitars as you will mess up a bunch of them.....

I use calibrated pin gages to carefully measure the clearance between the fret and each string.... But regular automotive feeler gages work great too.

Nut files are one of the best purchase I have made...

I guess it's possible bone dulls nut files faster than feeler gauges. Anyone want to rip one in two with their .010" nut file to see how it affects it? For science!

If you cut to stacked feeler gauges on a fender G string with no string tree, and do the same on a slot head acoustic with medium gauge strings you will have a very different height over the first fret. The string arks over the slot edge to varying degrees. A feeler gauge laying from the slot to the first doesn't take that into account. The thinnest gauge I have is.0015" Even if I could reliably tell when it was dragging on an .008" or.009" string, I would have to go down from there by eye anyway. Doesn't the plunger on the Stew Mac dial gauge deflect the string initially with spring tension or even just weight on a light string?

That is kind of my point. If you use the feeler gauge as a zero fret height, you can quickly file to that height, then sneak up on the final depth.

I'm not advocating this method for you as you have one that works for you, but am offering it as an option for the op who is starting out. For me this method has let me do very good setups quickly, and I've never cut a slot too deeply.

Different styles work for different people.

That makes sense to me Mike. I file down to a zero fret line made with a half pencil initially.
Just a different way of getting to the starting point. Maybe my fear of running my files onto a feeler gauge is irrational. It kind of gives me the nails on a chalkboard willies. I've ground some here and there and they always seemed pretty tough.

I started with the stacked feeler gauges in the late 90's but also quickly went to the flattened pencil line and then incrementally down referencing off the first fret for which there are many approaches.

One thing I found was not to take the slot to maximum depth right away especially on a new nut. It seemed the strings would bed in a little especially if you were following the nut work with saddle intonation and height adjustment requiring a lot of de-tuning and re-tuning. I usually wait until the strings have been slid back and forth in the slots a few times before taking the depth down to final limits.

Anyone else noticed that?

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

Terry I used to notice that until I paid more attention to cutting the slots wide enough as well. In some nut materials and even softer bone it seems to me that say a .013 file will tend to cut say a .011 slot when all is said and done and the file is withdrawn. This is particularly a problem with some non-bone materials such as some of the aftermarket alternatives, pl*stic nuts, etc. But even with bone if it's softer the slot really needs to be widened a bit AND the string always needs to be worked back down into the slot during the cutting process manually to be sure it's bottomed out.

A couple of years ago I started holding the files canted approx. 45 degrees side ways on the initial down strokes on both the right and left side of the slots. What's resulting for me is that the slots are more true to what I want to see when I measure with feeler gauges. An example would be a .014 slot from a .013 file, what I would want instead of something less that binds and gives me a artificial read on the bottom.

For everyone else I don't like the feeler gauge method or what we unaffectionately refer to as "training wheels" much at all. It would slow me down, lessen my accuracy, and provide NO prevention of going too low because I won't accept bottoming out on the files as as low as I can go and I want that last 5% or so. It makes a difference in feel.

At least 4 -5 times a day I put a guitar in someone's hands and let them try it out after a set-up. It's nearly universal that the face relaxes, a smug or happy smile forms, usually some comment such as "awesome" or even ^&*&&^% awesome... is heard and the reason why is the nut slots....

Do not underestimate the value of very well cut nut slots..... It's one of the most recognized forms of great value that Lutherie clients experience and they experience it nearly at once when done well. I'm often hearing that chords that were difficult before are easy now and we just helped someone realize their musical goals.

Fretting and holding between the 2nd and 3rd with a well adjusted truss rod and that's all that is necessary to cut nut slots very, very well. A movable task light because we are dealing with some gaps that are sub .001 at times and all that I can detect is the presence or absence of a sliver of light. It's hard to see but I can do it at 60 so I am sure that many of you guys can too.

Feeler gauges can't get me that low, take time to set-up, are more metal tools in a position to scratch someone else's valuable personal property...., and there is the risk of dulling files too for those of us who have to buy new nut files from time to time because we do a lot of this.

Pay attention to the ark that David talks about above. It's important and something that can be used to our advantage or hurt us if we are not aware of it.

Because of this ark it's possible to at times, not always, back file a slot that's too low increasing break angle in the slot and exploiting the ark of the stiffer strings and all of a sudden the slot is perfect and no longer too low.

There are very respected pro luthiers in the trade who will tell you that if a slot is not buzzing open it's not too low. I agree.

If you use quality nut materials, we like unbleached bone, be sure that your slots don't bind and are wide enough, practice and perfect your techniques nut slots are easy, fast and rewarding to do very well for folks and yourself as well.

One last nit. I save my old, dull files to follow-up after using a new sharp file. My files have a Sharpie "N" on them or the old, worn out "N" from last time to denote which is which. I keep two of each size, an old one and and a new one in my file box. Hitting the slots one last time or two with the duller files just to be sure that the bottom of the slot is not rough and likely to sink, as Terry noted, after it's cut. We don't want nut slots wearing too low prematurely and this is a hedge against that as well as widening the slots and being sure that the string is all the way bedded in the slot.

And really, really one last thing: I really struggled with this and I don't mind saying so.... I could not for the life of me figure out what I was doing wrong when at times my slot went below the line and the string was too high but then all of a sudden too low.... It truly sucked and pissed me off royally at times. Replacing nuts is something that back ten years or so ago was a common thing for me....

Cutting nut slots is an art and one of the most demanding things that we do in Lutherie when.... done.... very well..... As such it requires lots of practice and don't feel bad if as a builder you don't really get that practice. I didn't either. It's just another reason why doing repairs will make you a better builder and to some degree vice versa too.

One Lutherie school is fond of having the instructor approach the student, look at the nut, pick it up and exclaim "that's nice..." pitch it in the trash and then tell the student to make another one. It's said at this school that you need to make about 100 nuts to start to get the hang of it..... They keep a huge supply of counter top material for students to practice with.

Not exactly my or our style of teaching mind you and I personally would not appreciate the approach but the message is valid and clear, nut making, slot cutting, etc. takes practice.

Methods such as using feeler gauges or commercial jigs are IME more a crutch and likely even a disservice to those who really want to learn how to do this stuff and do it well.

On the upside. If more of you guys use feeler gauges and wreck your files more quickly maybe, just maybe we can talk Grobet into making those excellent nut files again.

One thing I learned at the Ann Arbor setup class is to measure your nut files. They are probably a few thousandths different then marked. Makes a difference.

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Steve Smith
"Music is what feelings sound like"

If you look at a nut file under magnification, even the good Gobbets, they are round-ish. Not fully radiused like a string. Some are down right flat on the edge. I think wound strings especially have to finish the rounding job until there is enough surface area to stop the bedding in.

You got that right ...which is why I have a set of these bad boys in different gauges to do the final slot rounding ..

Murray are the blades for that tool sharper than nut files? I'm wondering if that would be quicker for roughing in the slots too.

Does the blade flex at all, we don't want a hump in the center of the slot. A hump as we see when makers using something flexible such as a cord to cut sots creates a variable nut slot angle. It's less of an angle at the nut face and more of an angle at the exit. If that tool is rigid not a concern.

Thanks my friend!

I've been using the flattened pencil method since I started doing this stuff 25 years ago. At some point I thought mayeb Ican actually get better then what I am doing and everyone else seems to use feeler gauges so what the heck I will give it a try. THen I thought the exact same thing as the OP... I don't want to ruin my file nor my feeler gauges.

Not to mention that I have not blown a nut in many many years nad I started cutting too low using the finger gauges.

So I'm back to my good old cheap needle files and a half pencil. I find with the half pencil I can very quickly cut to jsut at the bottom of the pencil line and then fine tune it a bit below that.

I'm curious to know what the tool is that Murry is using?

Hallo and thanks alot for this jig it is reall clever!!Could i ask you what are you doing with the strings tha are not wound?

Not seen any of those on offer for a time...

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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.

Thanks everyone for responding and confirming that my concerns are valid. I will go about this cutting without the feeler gauges and only use them to check progress. I have a couple low dolar guitars that I purchased as practice projects that I plan to replace plastic nuts on and a refret for one also. I think for their inexpese I will take everyone's advise and purchase a few extra nut blanks for what will most likely happen. Thanks again and I'm sure I will be checking in for more advise in the future.

I like to mark the zero fret height position and work to that measurement -- rather than using a half pencil I fabricate a stylist from a 1/4 x 1/4 piece of spruce which produces a very fine, bright line. The method is shown here:
http://www.kennethmichaelguitars.com/zerofret.html

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Ken Cierp

http://www.kennethmichaelguitars.com/

Totally understand your concern, Hesh ... the "blade" of course is an actual guitar string under high tension...I use a small drop of abrasive paste (the same white stuff your wife uses on a cloth to clean ceramic surfaces in the kitchen) and use the far end of the string where it flexes least ( you know, the "clothesline effect"). If you hold the tool at the correct angle, there is no possibility of the string flexing back and creating a "center hump" in the slot.

I only use it for the final couple of light strokes, to ensure total roundness. I have a full set of StewMac nut files for initial slotting, but it is interesting that the string under tension will actually cut a slot in bone right from the git-go.... even without any abrasive paste to help the cutting action. You couldn't achieve this tension without a threaded adjuster of course ... a hacksaw frame won't cut the mustard (or the bone)


I just use the appropriate Stewmac nut file, after first marking with a razor saw. With the unwound strings, I don't really see perfect roundness in the slot as much of an issue ... the strings are not going to bind in the slot unless something really gross is going on.


I doubt if you will see them in the future either, Colin. There was just far too much work involved in manufacturing them to make it economic.

I'm afraid to ask this out loud Murray, for fear of upsetting the God's but, are you using this when the nut is on the instrument?
When a playing string breaks, it flies up and away from a guitar. What would happen if one broke on the frame in use?
No?

Murry, that looks like the cat's meow! Great idea. Someone needs to make those.... maybe just a metal C shape with a guitar tuner mounted on the end.

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Pat

Good point. I have never had one break in use but that's not to say it couldn't happen ... the worst case scenario would be that the point of the frame would plunge downwards and mar the headstock veneer. I tape behind and in front of the nut as a matter of course to stop any abrasive paste getting on the fretboard or the headstock . In future I will cut a section out of an aluminum beer can and tape that behind the nut as an additional shield to prevent headstock damage. There isn't a whole lot of pressure being exerted on the string, all that's needed is a light touch, but better safe than sorry.