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  #16  
Old 07-08-2014, 08:58 PM
NEGuy NEGuy is offline
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Quote:
Originally Posted by charles Tauber View Post
In my opinion and experience, measuring the clearance above the first fret is the hard way to do this. I'll tell you why.

The physical thing that is responsible for the height of the strings at the nut is the depth of the nut slot as measured from the top of the fingerboard to the bottom of each slot in the nut. (This assumes no zero fret.) The distance that the string is above the first fret is a derived consequence and cannot be adjusted directly. That is, an adjustment of the depth of the nut slot produces some result a distance away at the first fret. It is an indirect consequence of the depth of the nut slots.

In my opinion, the easier way to set the string height at the nut is to measure the height of the first fret and then cut the nut slots until they are that distance above the reference surface - the fingerboard. Theoretically, that will put the depth of the slots at exactly the height of the first fret. Practically, I find that adding .006 to .008, usually graduated from bass to treble strings, avoids buzzing at the first fret. I have no idea - nor is it relevant - what the actual measurement is between the top of the first fret and the bottom of the string.

Using the same feeler gage(s) used to measure the height of the first fret, laid on the same reference surface - top of fingerboard - simply file until you just touch the top of the feeler gage that is placed adjacent to the nut. You're done. Very simple.
Quote:
Originally Posted by Brhibler1 View Post
I do it this same way, but add .01 to my height.
So, the relevant range for the “direct” method (and, yes, I do see your point here) would seem to be 0.006” --> 0.010”.

Just for grins, if either (or both ) of you wouldn’t mind checking the “derived consequence” (i.e., the action height @ the 1st fret), I would be most appreciative.
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  #17  
Old 07-08-2014, 09:00 PM
NEGuy NEGuy is offline
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Quote:
Originally Posted by Frank Ford View Post
It is very EASY to see a gap of .001 between two closely spaced things, if there's strong light coming from behind. So, without any real effort at all, you can bend over and peer at the gap between the string and the first fret when the string is depressed between the second and third.

I think that's the key to the whole business of setting nut action. Now, if you look really closely as you work, and lift the string out of the nut slot, file a little, replace the string and look again, you can judge your progress as you go.

The difference between that little gap at the lowest possible action at the nut and the highest usable action is easy to judge visually - usually it's the difference between a gap of .001" and about .004, or a 4-to-one differential. Hard to miss if you're looking closely!

We do generally set the action at the nut so the gap is on the order of .002 for "normal use" but it's not uncommon to set it higher for a number of reasons - playing style is one. Bottleneck blues guys typically need it kinda high. . .
Okay, Frank – you’ve made a believer of me.

[I should probably add that I visited Gryphon Strings within the past month, and all the guitars that I sampled played wonderfully – with no fret buzz. Also, a very knowledgeable and experienced guitar enthusiast on this very site has recommended purchasing guitars from Gryphon because of the “added value” of your set-ups. ]

Anyway, I guess I was thinking of something “quantifiable” for the sake of precision, so if you use a feeler gauge at the 1st fret while fretting between the 2nd and the 3rd , then the clearance at the first fret for one of your standard set-ups is . . . what – ~ 0.002”?

This seems to be what you stated over at the UMGF.

(My present clearance is 0.010” – possibly even closer 0.012”. Too high!)

I should mention that the frets are all perfectly level (I checked with the StewMac metal straightedge).

I should also mention that a shim was placed underneath the nut to raise the action because it was initially too low (fret buzz). All the slots at the nut, the radii, etc. are proper; it’s just a matter of reducing the thickness of the shim to get the right action height at the nut.

So, Frank, if your “standard” clearance that you set at Gryphon is 0.002”, then I could shoot for 0.002” – 0.004”?

(Once again, all of the guitars that I played at Gryphon (4 or 5) were all buzz-free for me with my playing style.)

Thanks very much for your and all other responses – quite a learning experience!
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  #18  
Old 07-09-2014, 09:13 AM
arie arie is offline
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what's the reasoning of checking action over the first fret by capo'ing at the third?
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  #19  
Old 07-09-2014, 09:41 AM
LouieAtienza LouieAtienza is offline
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Quote:
Originally Posted by arie View Post
what's the reasoning of checking action over the first fret by capo'ing at the third?
The shallower the angle of the string is, the more accurate [to me] my measurement over the first fret is, but can still check relief at the same time.
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  #20  
Old 07-09-2014, 09:49 AM
NEGuy NEGuy is offline
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Quote:
Originally Posted by arie View Post
what's the reasoning of checking action over the first fret by capo'ing at the third?
Well, as Charles has mentioned, “the physical thing that is responsible for the height of the strings at the nut is the depth of the nut slot as measured from the top of the fingerboard to the bottom of each slot in the nut,” and the action at the first fret is really just a “derived consequence” of this and “cannot be adjusted directly.”

So Charles has his method of directly setting the “height of the strings at the nut” (by adding a few thousandths to the height of the 1st fret), but Frank’s method does this indirectly by capo’ing at the 3rd fret, thus allowing you to use the capo’ed string as a straight-edge.

I think the “reasoning” is that the triangulation that results from bringing the string over the 2nd fret and then just barely clearing the 1st fret gives you just those few thousandths at the nut that Charles is adding directly.

Anyway, that’s my take.

What I appreciate about all the responses in this thread is that I now have a lot of different perspectives that were shared on this issue (a present issue for me!) and thus a lot of ways to “cross check,” so to speak.
.
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  #21  
Old 07-09-2014, 10:40 AM
arie arie is offline
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thanks for the clarifications. ime though, any measurement that has less of a chance of being influenced by random variables: capos, fingers, neck relief, individual fret heights, business cards, paper shims, feeler gages, etc... is a more accurate and repeatable measurement -jmo. i'm not trying to tell anybody how to do their work just to consider some factors that's all.
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  #22  
Old 07-09-2014, 11:08 AM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by arie View Post
less of a chance of being influenced by random variables:
The entirety of setup work is "random", by your statement. It is based on what exists - the geometry - at the time you set it up. That isn't random, it is a relatively static set of data (datums, in popular language) with which to work. The string height has to be set relative to something. Pick what that something is. But, you're point is well-taken, to choose data that are as static as possible.

For example, the thickness of the fingerboard is pretty static. So is the height of one (the first) fret above that. Those are two of the data I prefer.

Similarly, using Frank's method, the height of the first two frets can be considered static as well. If they aren't, trying to setup an instrument with constantly changing geometry is an exercise in futility. Ever tried to setup a guitar with a very flexible neck, like a whammy bar? While playing it, the action (and intonation) constantly change.

I like Frank's method. I just got tired of cutting nut slots too deep or having to inch (.0001?) my way down to the desired height by trial and error. Using feeler gages - a method I learned from Dan Earlwine - allows me to usually cut/file once and be done with it and with repeatable results. I'm all for doing things by eye that can be.

There are many viable ways to accomplish nearly any task. One picks the one that one likes. That varies from one person to the next.

Last edited by charles Tauber; 07-09-2014 at 11:17 AM.
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  #23  
Old 07-09-2014, 11:47 AM
NEGuy NEGuy is offline
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Quote:
Originally Posted by arie View Post
thanks for the clarifications. ime though, any measurement that has less of a chance of being influenced by random variables: capos, fingers, neck relief, individual fret heights, business cards, paper shims, feeler gages, etc... is a more accurate and repeatable measurement -jmo. i'm not trying to tell anybody how to do their work just to consider some factors that's all.
Point well taken.

I think my reasoning goes something like this:

All procedures that I have read in this area recommended getting the relief set first – so that variable is already out of the picture.

Also, the bridge height won’t be relevant since I’ll be fretting at the 3rd fret.

The fret height *is* relevant, but I would *want* this to be relevant since the frets are the precise structures that I’m trying to clear with the proper clearance – and I have already checked relief and ensured that all frets are indeed level.

And the string, of course, is a true straight-edge.

I think my one concern was that Frank seems to “eyeball” the clearance at the 1st fret, and, as an accomplished luthier, I’m sure he knows just what to look for.

He seems to think that the clearance is relatively easy to judge with a bright light shining from behind through the gap (a post of his either here or at the UMGF), but I’ll probably use a trusty feeler gauge.
.
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  #24  
Old 07-12-2014, 04:00 PM
murrmac123 murrmac123 is offline
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Quote:
Originally Posted by charles Tauber View Post
In my opinion and experience, measuring the clearance above the first fret is the hard way to do this. I'll tell you why.

The physical thing that is responsible for the height of the strings at the nut is the depth of the nut slot as measured from the top of the fingerboard to the bottom of each slot in the nut. (This assumes no zero fret.) The distance that the string is above the first fret is a derived consequence and cannot be adjusted directly. That is, an adjustment of the depth of the nut slot produces some result a distance away at the first fret. It is an indirect consequence of the depth of the nut slots.

In my opinion, the easier way to set the string height at the nut is to measure the height of the first fret and then cut the nut slots until they are that distance above the reference surface - the fingerboard. Theoretically, that will put the depth of the slots at exactly the height of the first fret. Practically, I find that adding .006 to .008, usually graduated from bass to treble strings, avoids buzzing at the first fret. I have no idea - nor is it relevant - what the actual measurement is between the top of the first fret and the bottom of the string.

Using the same feeler gage(s) used to measure the height of the first fret, laid on the same reference surface - top of fingerboard - simply file until you just touch the top of the feeler gage that is placed adjacent to the nut. You're done. Very simple.

I agree, totally, with every part of this post by Charles.

(apart from his spelling of "gauge" that is ...other than that .. right on Charles)
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  #25  
Old 07-12-2014, 06:46 PM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by murrmac123 View Post
(apart from his spelling of "gauge" that is ...other than that .. right on Charles)
It's confusing for me. I never know when to use the 'Merican spelling vs. Canadian/British. 'Merican's don't use the extra "u".
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  #26  
Old 07-12-2014, 06:58 PM
Scallywag Scallywag is offline
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I began the most recent setup on my personal guitar, strung with medium gauge strings (13-56), with the following nut slot measurements (open strings, first fret. Very slight neck relief):

E = .018", A = .016", D = .016", G = .016", B = .016", E = .014"

FYI, I use this as a starting point. It is fairly low. Often times one or more of the slots will end up being filed slightly deeper but I have found this to be a very good starting point for the low action that I prefer (for fingerstyle, which I play exclusively on this guitar.) Should you prefer slightly higher action you might file the slots a bit more shallowly and adjust from there, to be safe.

Last edited by Scallywag; 07-12-2014 at 09:47 PM.
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  #27  
Old 07-13-2014, 08:16 AM
John Arnold John Arnold is offline
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Quote:
there is no standard
Yes, there is. The correct nut height is the same as the frets....because placing a capo in the first fret creates a new 'nut' that is exactly that high. If it doesn't buzz when capoed there, it should not buzz when the nut is the same height.
When you press the string down between the second and third frets, you are theoretically creating a straightedge between the second fret and the nut. But because the string bends across the nut, it actually rises a bit as it crosses from the nut toward the fingerboard. That is one reason why a slight visible space (0.001" to 0.002") over the first fret seems to work best. Another reason for extra clearance is to avoid back buzzes, which are mainly a problem on the 6th string.

If you set the nut height the same as the frets, then the first fret action is automatically determined by the saddle height. In other words, you never have to measure the first fret action, and I never do.

The distance between the nut and first fret is 11.2% of the distance between the nut and 12th fret. Assuming the neck is straight and the nut is set at fret height, the action at the first fret should be 11.2% of the action at the 12th. In other words, unless your 12th fret action is over 3/16", an action of 0.023" at the first fret is way too high. A 12th fret action of 3/32" (0.094") should result in a first fret action of 0.011".

Quote:
It's confusing for me
If you pronounce the 'gu' as 'gw' (e.g. 'Guam' or 'guacamole'), then you will know that 'gauge' is not spelled 'guage'.
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  #28  
Old 07-13-2014, 08:57 AM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by John Arnold View Post
If you pronounce the 'gu' as 'gw' (e.g. 'Guam' or 'guacamole'), then you will know that 'gauge' is not spelled 'guage'.
In Canada, it is spelled gauge. We also have colour (color), metre (meter) and pronounce the letter "zee" as "zed", as in zedbra. And of course, cheques (checks) - the things you make out to someone and sign for a specific amount.

If I'm writing for or speaking to 'Mericans I use one; if I'm writing for or speaking to Canucks, I use the other. The confusion is deciding in what country I'm writing for or speaking to. The spell-checker usually, but inconsistently, flags American spellings, versus Canadian ones, as errors.

Murray's complaint was my use of the American spelling, "gage".
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  #29  
Old 07-13-2014, 11:07 AM
LouieAtienza LouieAtienza is offline
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Well if you`re a Yankee, spell it gage. If you`re a Canuck or across the pond, use gauge. Either way is acceptabe in the US.


And. I thought you Canucks were dyslexic!
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  #30  
Old 07-16-2014, 01:02 PM
NEGuy NEGuy is offline
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Quote:
Originally Posted by John Arnold View Post
Yes, there is. The correct nut height is the same as the frets....because placing a capo in the first fret creates a new 'nut' that is exactly that high. If it doesn't buzz when capoed there, it should not buzz when the nut is the same height.
When you press the string down between the second and third frets, you are theoretically creating a straightedge between the second fret and the nut. But because the string bends across the nut, it actually rises a bit as it crosses from the nut toward the fingerboard. That is one reason why a slight visible space (0.001" to 0.002") over the first fret seems to work best. Another reason for extra clearance is to avoid back buzzes, which are mainly a problem on the 6th string.

If you set the nut height the same as the frets, then the first fret action is automatically determined by the saddle height. In other words, you never have to measure the first fret action, and I never do.

The distance between the nut and first fret is 11.2% of the distance between the nut and 12th fret. Assuming the neck is straight and the nut is set at fret height, the action at the first fret should be 11.2% of the action at the 12th. In other words, unless your 12th fret action is over 3/16", an action of 0.023" at the first fret is way too high. A 12th fret action of 3/32" (0.094") should result in a first fret action of 0.011".
I tried this procedure on my last string change (it certainly makes sense), and, frankly, I am dumbfounded by the results.

I used a StewMac straight-edge between the 2nd fret and the nut slot of the low E string (since there is obviously no string under tension during a string change, so I cannot use a string), and I saw no clearance between the straight-edge and the 1st fret. I had my wife shining a bright light from behind – as Frank recommends – so I think (?!) I am certain of this!

Anyway, I string up the guitar, and the action at the 1st fret is still 0.033” – way too high!

So it would seem that this is totally an issue of the bridge being too high, right?

But when I fret the low E string between the 2nd & 3rd frets (after the new strings are installed), I get a clearance of 0.011” at the 1st fret!

Where did that come from?! There was no visible clearance with the StewMac straight-edge before I strung it up!

Has anyone ever experienced anything like this?

The frets are level. Relief is good – so I just want to get the nut down to where it needs to be.

By the way, the 1st fret action is 0.033”, and the 12th fret action is 0.105”, so .033/.105 --> 31.4% (Therefore the nut is way too high, right?)

Possibly I will try Charles’ “direct” method at the next string change – which brings me to this:

Quote:
Originally Posted by charles Tauber View Post
The easier way to set the string height at the nut is to measure the height of the first fret and then cut the nut slots until they are that distance above the reference surface - the fingerboard. Theoretically, that will put the depth of the slots at exactly the height of the first fret. Practically, I find that adding .006 to .008, usually graduated from bass to treble strings, avoids buzzing at the first fret. I have no idea - nor is it relevant - what the actual measurement is between the top of the first fret and the bottom of the string.
This procedure certainly makes sense as well, but I am puzzled by one statement.

You say that you add “.006 to .008, usually graduated from bass to treble strings.”

I might be confused, but wouldn’t you want the clearance to *decrease* as you go from the bass E string to the treble E string?

Thanks for any and all replies.
.
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