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Equation for nut adjustment measure at 12
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Author:  SnowManSnow [ Sun Jan 12, 2020 9:50 am ]
Post subject:  Equation for nut adjustment measure at 12

So how does nut adjustment affect 12 fret action?Since it is half the scale length is it the same if adjusting the saddle... half ?
B


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Author:  B. Howard [ Sun Jan 12, 2020 11:40 am ]
Post subject:  Re: Equation for nut adjustment measure at 12

Exactly the same as making the same height adjustment at the bridge.

Author:  Barry Daniels [ Sun Jan 12, 2020 11:55 am ]
Post subject:  Re: Equation for nut adjustment measure at 12

In theory, that is correct. But in practice you do not adjust action with the nut. For one thing, when you fret a string you take the nut out of the equation. And you should already have the strings at the nut as low as possible. Setup the nut first and then set the action with the saddle.

Author:  Chris Pile [ Sun Jan 12, 2020 11:57 am ]
Post subject:  Re: Equation for nut adjustment measure at 12

Quote:
Setup the nut first and then set the action with the saddle.


NO!

You set the bridge action FIRST, then the nut.
Come on, Barry.

Author:  Barry Daniels [ Sun Jan 12, 2020 12:07 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

Not me. It probably does not make a big difference either way. But that is the way that I was taught and have been doing it for 44 years.


When I setup the saddle, I measure the action at the 12th fret while fretting the string at the first fret which takes the nut out of the equation. When I setup the nut, I fret the string at the 3rd fret which takes the bridge out of the equation. So it really makes no difference, right?

Let's keep this friendly please.

Author:  Chris Pile [ Sun Jan 12, 2020 12:12 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

Quote:
So it really makes no difference, right?


It dang sure does.

Author:  Barry Daniels [ Sun Jan 12, 2020 12:20 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

I'm not going to debate this with you Chris, because you have never demonstrated the ability to have a respectful discussion about anything.

Author:  SteveSmith [ Sun Jan 12, 2020 12:21 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

I do the nut first - way I was taught.

Author:  Colin North [ Sun Jan 12, 2020 12:35 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

I've always set 1) relief, 2) nut slot height 3) saddle height for action, in that order, as I have seen advised on many posts here from the likes of Hesh and others.
The saddle is out of the picture as I set the nut slot height with the string fretted at the 3rd fret, as Barry said.

Author:  SnowManSnow [ Sun Jan 12, 2020 1:00 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

To be clear. I’m not asking how to set action at the 12th by adjusting the nut. I’m asking how to predict what changes any slot changes will make at the 12th.
The second post answered as I thought, I just wanted to make sure I was thinking right .


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Author:  bluescreek [ Sun Jan 12, 2020 1:26 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

with Colin
relief
nut slot
then action height.
neck relief is important and that should be pretty static.
1st to 12th fret
straight edge .004 to .006 at the 6th fret off the straight edge
Nut slot has a limit and I start that about .006 off the top of 1st fret
The action is then adjusted off the saddle

You may tweak the nut but here we are talking a few thousandths of an inch

Author:  John Arnold [ Sun Jan 12, 2020 1:32 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

The only reason for adjusting tha saddle before the nut is because of the practice of measuring the nut height by checking first fret action. I never measure action at the first fret. If you don't evaluate nut height that way, you can set the nut adjustment before the saddle.
If you understand that there is only one correct nut height (same as fret plane), then it makes no sense to even measure the first fret action. If the nut height is correct, first fret action will always be 11.2% of the 12th fret action.

Relief, nut, then saddle last.

To elaborate on the OP question:
Though the nut and saddle height have equal effect on the 12th fret action, the nut adjustment is much more critical, since the majority of the fretting is on that half of the string. In other words, a 0.010" change in nut height has a much more profound effect on playability than a 0.010" change in saddle height.

Author:  meddlingfool [ Sun Jan 12, 2020 2:17 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

Interesting. I'm with Chris. But I guess it depends on how close your starting measurements are in the first place.

If you get your nut just exactly right, and then drop the action at the saddle, it's entirely possible then that the minimum clearance at the nut will no longer be enough, and you'll get buzzing on the open strings.

Since the adjustments at the nut will be in very small increments usually, like only a few thou, the effect at the 12th fret will be negligible. But since you can easily be making adjustments of 40-60 thou or more at the saddle to get the 12th fret height where you want it, those adjustments can eat your clearance at the nut.

So I do relief, string action, nut tweak. But then my nuts all start off pretty close to where I want to end up anyway, using a generic height across all strings guaranteed to be safe. Then I come back last to tweak according to what the fret itself dictates. Cause I hate making nuts so I try to avoid redo's...

Author:  Chris Pile [ Sun Jan 12, 2020 2:29 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

Quote:
I'm not going to debate this with you Chris, because you have never demonstrated the ability to have a respectful discussion about anything.


You're not going to debate me because you're wrong.

Author:  Barry Daniels [ Sun Jan 12, 2020 2:59 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

Thanks for proving my point.

Author:  Chris Pile [ Sun Jan 12, 2020 3:38 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

And mine.

Author:  Hesh [ Sun Jan 12, 2020 3:42 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

Here's what I do and I'm the set-up guy with hundreds of real five star reviews from players. I set-up around 600 guitars annually and have been doing so for over a decade now. This is not a discussion for me or with me it's how I do it and how my clients love it and rave about my work.

If it pisses anyone off that I sound proud of what I do and sure of myself that's not my intent nor will I apologize. What is my intent is to make it crystal clear that this is not an academic pursuit for me it is instead how I paid off my mortgage on my condo and recently bought a new car.

Results matter...

1). Adjust truss rod. I want the treble side nearly flat with minimal relief and more relief on the bass side if the neck will do this, most won't. So I have to compromise on the ones that won't behave as I want unless I am doing a fret dress and then I can shape the fret plane to do what I want with ease, refret too. Anyway without throwing the bass side into back bow I want the treble side nearly straight, minimal relief.

2). I fret and hold between the 2nd and 3rd fret and tap the string over the first fret crown and observe the space. For the high e and b I want no observable space in how low I will cut the nut slot. I still don't want contact with the fret unless I'm taping it so that "tink" sound is desirable to hear. How much space to I leave for the high e and b when fretted and held between the 2nd and 3rd? We've measured it around .0005" barely something that an be observed but experience tells us because of the "tink" sound that the string is not laying on the first fret.

For each progressively fatter string the space increases and I can't give you a measurement nor do we use one but it's less than half the diameter of the respective string after the high e and b.

3). Now that the rod is adjusted, the nuts slots are all cut very low which by the way will for 99% of steel string players eliminate intonation issues that nut compensation is supposed to address making nut compensation not necessary or desirable.....

I measure the action of the high and low e's respectively at the 12th fret. We have industry specs for set-ups that we use as a baseline and modify accordingly from there for finger style players, cowboy chord sorts, shredders, drop tunings and ham fisted folks.

For say a dr*ad with 13's with a blue grass player 4.5/64" for the high e and 6.5/64" for the low e is pretty standard. For a Strat with 10's 4 and 4.5 (speaking in 64th" at the 12th with the high e always mentioned first).

Dave and I communicate this way. He might wait on the client when I'm not there and my tag might say <4 and 4 and I know he's wanting low action (this would be an electric and too low for most acoustics).

So it's rod, nut slots and then what ever I observe at the 12th is written down for an acoustic and the saddle is removed, marked, milled down and sometimes shimmed up whatever it needs to meet that action that I want. For say a finger style OM 4 - 5 is what I set my acoustics at.

Food for thought. If I want to take the action down 1/64th" at the 12th on the low e I remove the saddle and mark a line that is 1/32nd" to be milled off on the bass side of the saddle. Why 32nds on the saddle and not 64th"? Because the saddle is the other half the distance from the 12th fret so we roughly double the measurement.

More food for thought. If you are new at cutting nut slots and most folks here are since you have not cut 30,000 nut slots yet perhaps set the rod for less relief than you want and then you have some margin for error.

One of our claims to fame at Ann Arbor Guitars and something that we can tell if we worked on an instrument prior is we take the nut slots WAY lower than anyone else we know except Elderly and Collings Guitars.

To recap, rod, nut slots, adjust action with the saddle(s) then. On electrics with independent saddles be sure to preserve the fret board radius including if it's compound. For acoustics be sure to check to be sure the saddle radius is OK.

Author:  Hesh [ Sun Jan 12, 2020 3:51 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

meddlingfool wrote:
If you get your nut just exactly right, and then drop the action at the saddle, it's entirely possible then that the minimum clearance at the nut will no longer be enough, and you'll get buzzing on the open strings.

.


No - If you cut nut slots accurately as I described in my prior post they will not be too low when lowering the saddle. The method described permits very precise nut slot cutting completely independent of the action measurements since the notes are fretted the action is taken out of play.

Set-ups, really good ones are sequential in their methodology eventually and in a specific order addressing all elements.

Author:  Hesh [ Sun Jan 12, 2020 3:54 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

One last thing then I have to go to the bathroom....

If you do your action adjustments at the saddle(s) and then find your nut slots too high and address them you may have to raise the action at the saddles. the method I described never has to back track for anything since the nut slots are set independently of the action and the first thing we do after setting the rod.

Chris and I do a lot of Floyd equipped axes and it's the same thing only I remove the metal nut and with a cup of water near by remove material from the bottom of the Floyd nut until it's as low as I want it. Lots of folks intentionally go too low with these and shim them back up, that's fine too.

Author:  Hesh [ Sun Jan 12, 2020 4:05 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

John Arnold wrote:
The only reason for adjusting tha saddle before the nut is because of the practice of measuring the nut height by checking first fret action. I never measure action at the first fret. If you don't evaluate nut height that way, you can set the nut adjustment before the saddle.
If you understand that there is only one correct nut height (same as fret plane), then it makes no sense to even measure the first fret action. If the nut height is correct, first fret action will always be 11.2% of the 12th fret action.

Relief, nut, then saddle last.

To elaborate on the OP question:
Though the nut and saddle height have equal effect on the 12th fret action, the nut adjustment is much more critical, since the majority of the fretting is on that half of the string. In other words, a 0.010" change in nut height has a much more profound effect on playability than a 0.010" change in saddle height.


Thank You and this is how we do it too.

Author:  Hesh [ Sun Jan 12, 2020 4:08 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

bluescreek wrote:
with Colin
relief
nut slot
then action height.
neck relief is important and that should be pretty static.
1st to 12th fret
straight edge .004 to .006 at the 6th fret off the straight edge
Nut slot has a limit and I start that about .006 off the top of 1st fret
The action is then adjusted off the saddle

You may tweak the nut but here we are talking a few thousandths of an inch


Thank You too John. We take our slots lower than .006 but that's pretty low. When I first started working with Dave Collins he was taking nut slot lower than my eyes were capable of perceiving. Now with practice I can see it AND it really helps to have dentist stuff with light cured dental fillings for when I go too low....:).

Author:  Glen H [ Sun Jan 12, 2020 4:34 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

Well shucks, only got 29,998 nuts to go.

Author:  George L [ Sun Jan 12, 2020 4:50 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

I've tried everything and this is how my setups typically go:

Relief
Nut
Saddle
idunno What the ...?
Nut
Nut
Nut
Relief
Saddle
Saddle
Crap!
[uncle] Make a new saddle
Relief
Nut
Saddle
Saddle
Nut
Nut
[headinwall] Refret
Relief
Nut
Saddle
:( Make a new nut
Relief
Nut
Saddle
Nut
Saddle
Saddle
Saddle
Saddle
Saddle
Bingo!

Oh, yeah! I'm a luthier, baby!! bliss

Author:  Barry Daniels [ Sun Jan 12, 2020 6:07 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

Hesh, according to someone here you are doing it all wrong.

Author:  meddlingfool [ Sun Jan 12, 2020 6:15 pm ]
Post subject:  Re: Equation for nut adjustment measure at 12

We will have to agree to disagree without being disagreeable..:)

I don't see how that .0005" clearance over the fret would not disappear if you dropped the action at the 12th by 1/16", but I also haven't crunched the numbers. I know that the two or three thou final nut adjustment will have essentially no effect on the action at the 12th.

Anyhow, that's how and why I do, I've also done tremendous numbers, I mean, really, really great numbers, you can just ask anybody, and have people come to me to get their guitars set up etc, and have made my living at it for 23 years and so on, so it may be that both methods work just fine.

Naturally, since I've been doing it this way all along with great results, I'm disinclined to believe your way is bettter, lol!

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