String Height Adjustment Question

Construction and repair of Classical Guitar and related instruments
dj2066

String Height Adjustment Question

Post by dj2066 » Tue Oct 03, 2006 4:57 pm

Hi,

I have an Almansa 302 guitar and would like to lower the string relief per my instructors recommendation.

He said to do this during my next string change and that I should remove the saddle and sand it down to the 'desired' string relief since the action is a little too high.

Questions:

1) What is a desired string relief dimension? Where and how do you measure it?

2) What is the recommended method to sand down the saddle to achieve the desired string relief?

Thanks in advance!

Doug

Derry

Post by Derry » Tue Oct 03, 2006 6:11 pm

my two better guitars measure about 3.5 mm at the 12th fret on the low e string,, high e is just a tad under the 3 mm at the 12th..

would do this adjustment over a few string changes if your doing it yourself cause if too much is taken off the bridge you can't put it back,,

make sure you know the present string height at the 12th fret for both e strings,, do you have any buzzing when playing strong rest stroke at any location on the neck,, if there is any now you will have more with the lower action,, make sure the neck is straight when sighting down it from the lower bout,,

with the saddle out I would measure the height on both ends to be sure of your starting point,, sand the bottom on a good flat surface with 220 grit or even 400 grit and remove about 1/32 for the first pass,, install saddle then install strings, play and take measurments for height,,

if it is still not low enough would remove the strings and go for another 1/32 until it is what your seeking,, run all the strings with a strong rest stroke on each fret up to the 12th to be sure there is no buzzing after each 1/32 is removed,,

Guitar Slim

Post by Guitar Slim » Tue Oct 03, 2006 6:41 pm

While I really don't like to go against your teacher's advice, I strongly recommend you take your guitar to a qualified builder or repair person and have a professional setup done. Just make sure you find one who specializes in classical guitars. A setup shouldn't cost you more than $50, I've had mine done for $35 by a very good local luthier. You should be able to find someone qualified a city the size of Toronto.

I'm not a pro myself, but I've done this a couple of times -- with varying results! But here's what I know, from my amateur perspective:

String height is usually measured at the 12th fret, from the bottom of the string to the top of the fret. The strings should be fretted or capo'd at the first fret before making the measurement. You can measure with a small precision rule.

Just as a general baseline, I found some measurments on Kenny Hill's website. He sets up his guitars for 3.2 mm on the 6th string, and 2.7 mm on the 1st. Theoretically, you can sand down the saddle to go lower than that without buzzing, but there are other factors involved like the nut height and the neck relief. A tech who knows their stuff will take all of this into account when doing the adjustments, and may adjust the nut as well as the saddle.

They say you must reduce the saddle 2mm for every 1mm of reduction at the 12th fret. This kind of scares me, though. 2mm seems like a lot to take off the saddle when you actually get down to doing it. If you're doing it yourself, do it in small increments -- 1mm at a time max, then restring the guitar and see how it feels. If it's still too high, sand off a little more etc, until you get it to where you want it.

Oh yeah, make sure you sand from the bottom! The top of the saddle is polished and specially shaped, you don't want to mess with that. And make sure you replace it facing in the right direction. Most saddles are tapered or curved toward the back. The side that faces the neck is somewhat higher, with a somehwhat sharper edge.

You don't need any kind of special sandpaper, I guess. Not too coarse, but it doesn't need to be super fine either. Just make sure you sand the saddle evenly and level, and the bottom of the saddle is flat so the maximum surface area is making contact with the bottom of the bridge slot.

And remember, lowering the saddle can effect your sound, even if you are still buzz-free. A lower saddle means less pressure on the bridge, which can cause loss of volume and sustain. I made this mistake a while ago -- took my saddle down as "low as it could go", and even though it wasn't buzzing, I really hated the way it sounded.

And if you screw up, you can always take it to a pro after all. Only now you'll have to pay for a new saddle as well as the setup, and it will cost you twice as much.
Last edited by Guitar Slim on Wed Oct 04, 2006 6:35 pm, edited 1 time in total.

Sasquatch51

Post by Sasquatch51 » Wed Oct 04, 2006 2:57 am

Guitar Slim wrote:The strings should be fretted or capo'd at the first fret before making the measurement.
I've never done this when adjusting the saddle. I do when I'm checking neck relief, but not adjusting the sadlle.

Guitar Slim

Post by Guitar Slim » Wed Oct 04, 2006 3:39 am

Sasquatch51 wrote:
Guitar Slim wrote:The strings should be fretted or capo'd at the first fret before making the measurement.
I've never done this when adjusting the saddle. I do when I'm checking neck relief, but not adjusting the sadlle.
As I say, I'm not an expert. But Hill measures the saddle height from the top of the 1st fret, not the bottom of the nut groove, taking his measurement at the 12th fret.

Kenny Hill:
I measure the saddle height by laying a straight edge on the 1st fret and the bone saddle, and measuring at the 12th fret. This can also be measured without a straight edge by just fretting the string at the 1st fret, but since a string is flexible, and round, it's harder to get an exact measurement. My standard "average" height is 3.2 mm for the 6th string and 2.7 mm for the 1st string.
I can't find my copy at the moment, but I believe the first time I saw this method used was in Dan Erlewine's Guitar Player Repair Guide.

It's all relative I guess, but if you're actually taking measurements and comparing them to a pro setup, you probably should make sure you're using the same method as whatever expert your getting your recommendations from. The two different methods will yield different measurements.

Again, I could be wrong. Any luthiers want to weigh in on the issue? I'm genuinely curious if this is a universal method for measuring action, or if it's common to measure from the nut, not the first fret.

Ronald Coates

Post by Ronald Coates » Wed Oct 04, 2006 6:07 am

Measuring at the 12th fret with a capoed 1st fret or the string resting in the nut. Really doesn't matter much. Of course your measurements will be different but..?

As stated the movement of the saddle down 2mm will result in a downward movement of the string at the 12th fret 1mm. More simply said you must define the desired adjustment at the 12th fret and then move twice that at the saddle. Why? because the 12th fret is at the half way point between nut and saddle. So consequently, movement at the nut has the same affect on string height at the 12 fret. So if you capo at 1 You will lower the string height at 12 by half of whatever the string height was above the first fret. Confused?

The thing to look at is this, string height above the 1st fret is not much... less than 1mm perhaps. It depends on how your nut was cut. So capoing at 1 is going to change the string height at 12 not much again. So why capo at 1? The only reason I can see is to eliminate the nut from the equation. That said, I don't bother. I get the 12th fret string height about right then cut my nut and then tweek the 12th fret height.

As said before how low you can go depends on a lot of things. Take it slow sand the bottom of the saddle to get your height. Keep it flat and straight and go slow. It's easy to take more off. It's hard to put some back on...

Keep in mind all these measurements are from the top of the fret to the bottom of the string. Typical seems to be in the 3.0mm to 4.0mm area some like it even higher.

Guitar Slim

Post by Guitar Slim » Wed Oct 04, 2006 6:29 am

Ronald Coates wrote:Measuring at the 12th fret with a capoed 1st fret or the string resting in the nut. Really doesn't matter much.
Sure, if your only frame of reference is your own guitar. If you're only measuring to see how much change there's been from a previous measurement on the same instrument, then it really doesn't matter. Like I said, it's all relative.

But my point was this: Doug asked for specific measurements. If you are comparing your own string height to some standard or to someone else's setup, then it is important to use the same method.

So if Doug wanted to measure his action against, say, Kenny Hill's or Dan Erlewine's, he would want to use the same method of measuerment. Even if the difference is only .5 mm or less -- that difference can still be significant, especially if you are shooting for very low action. 0.5mm can be the difference between a relatively clean sound and a nasty buzz.

Ronald Coates

Post by Ronald Coates » Wed Oct 04, 2006 8:45 pm

Guitar Slim wrote:[
But my point was this: Doug asked for specific measurements. If you are comparing your own string height to some standard or to someone else's setup, then it is important to use the same method.

Even if the difference is only .5 mm or less -- that difference can still be significant, especially if you are shooting for very low action. 0.5mm can be the difference between a relatively clean sound and a nasty buzz.
All of this is quite true, although I can't imagine why I would care about Hill's set up. Then again this isn't about me is it? You're right doug asked for specifics. Here is trhe point. You wrote ;

"Even if the difference is only .5 mm or less -- that difference can still be significant..,"

Exactlly! Your string height at 12 is not only dependant on the saddle height but also the height at the nut. If your nut is lower than Hill's and you capo and set the saddle height equal to Hill's then the uncapoed string height of your guitar will be lower, potential buzz. If your nut is cut higher your action ends up higher. You don't know until you measure and set it up taking all three points (nut, 12th fret, and saddle) into account. All of this still doesn't take into account the taper built (or not) into the fingerboard. So forget about comparing to some one elses guitar set up your guitar.

When setting up a guitar correctly all things must be considered as pieces of the puzzle. If we leave out a piece, we may be able to see the picture, but it's still incomplete.

Sasquatch51

Post by Sasquatch51 » Wed Oct 04, 2006 10:44 pm

What is the purpose in capoing at the first fret to check string height?

Guitar Slim

Post by Guitar Slim » Wed Oct 04, 2006 11:48 pm

Ronald Coates wrote: All of this is quite true, although I can't imagine why I would care about Hill's set up.
Maybe because he's a well-known and respected maker of classical guitars?

No need to be a smart alec, Ron. Doug asked for specific measurements. A quick search of the internet turned up this article by Hill, with the specific measurements Doug was looking for, and Hill's method for taking those measurements. I thought Doug might find it useful.

BTW, here's a link to Hill's site if anyone (other than Ron) cares to read it:
:arrow: http://www.hillguitar.com/
Click on the "news" link to find a number of articles Hill has written, including the one on setting up a classical guitar.

Sasquatch, I'm not sure why saddle height is measured from the first fret and not from the nut. I just know that several sources I've encountered recommend this method, and if I'm comparing my measurements to theirs, I would prefer to use thier method for the sake or accuracy.

I'm just speculating, but fretting at the first fret takes the nut out of the equation, right. String buzz that is caused by a low saddle usually occurs when fretting notes, so the nut is not a factor anyway (well, unless you're talking about "back buzz"). If you are getting buzz from unfretted, open notes, then the problem probably is with the nut and not the saddle height (unless your action is way too low).

Like I said, I'm not an expert. I'm just passing on what I've read and heard from those who are.

alter Ton

Post by alter Ton » Thu Oct 05, 2006 2:35 am

Guitar Slim wrote:
Ronald Coates wrote: All of this is quite true, although I can't imagine why I would care about Hill's set up.
Maybe because he's a well-known and respected maker of classical guitars?

No need to be a smart alec, Ron. Doug asked for specific measurements. A quick search of the internet turned up this article by Hill, with the specific measurements Doug was looking for, and Hill's method for taking those measurements. I thought Doug might find it useful.

BTW, here's a link to Hill's site if anyone (other than Ron) cares to read it:
:arrow: http://www.hillguitar.com/
Click on the "news" link to find a number of articles Hill has written, including the one on setting up a classical guitar.

Sasquatch, I'm not sure why saddle height is measured from the first fret and not from the nut. I just know that several sources I've encountered recommend this method, and if I'm comparing my measurements to theirs, I would prefer to use thier method for the sake or accuracy.

I'm just speculating, but fretting at the first fret takes the nut out of the equation, right. String buzz that is caused by a low saddle usually occurs when fretting notes, so the nut is not a factor anyway (well, unless you're talking about "back buzz"). If you are getting buzz from unfretted, open notes, then the problem probably is with the nut and not the saddle height (unless your action is way too low).

Like I said, I'm not an expert. I'm just passing on what I've read and heard from those who are.

To be honest, I don't understand how measuring the action with the first fret capoed gives a meaningful measure with regards to playability, unless you actually play with a capo on the first fret all the time. We measure the action to get an idea of how difficult a guitar may be to play, taking the measure in a manner which doesn't reflect at all what the player will encounter seems to be kind of meaningless, but I am not a luthier. My guitars action was measured without depressing the strings.

Ronald Coates

Post by Ronald Coates » Thu Oct 05, 2006 3:02 am

Chris

I wasn't try to be flipant. If I came across that way I apologize. I meant why would I care about hill's set up or anyone elses... In that you need to set up the guitar based on what you have in that specific guitar. Again sorry for any hostility that came across in my post. None intended.

Look at it using an extreme(impossible) example Do your measurements with a capo on a guitar with a nut that is 6 inches tall. After you get your 3.5mm height at the 12th fret you remove the capo and what have you got? Still aguitar you can't play. Likewise if you do the same with a guitar whos nut is cut so that the open strings buzz wildly, after setting up the 12th fret action with the capo on one the guitar will still be unplayable.

Extreme examples to be sure but illustrative of the fact that we can't just discount the nut in the set up of the guitar. Perhaps we could say this is more important in the restoration or building of a guitar. A playable guitar should have a reasonable nut set up to begin with, so if we just want a lower äction then a simple saddle adjustment will achieve that and wether we measure that adjustment from the basis of a capoed measurement or uncapoed should again matter... not much.

While I believe it's safe to say that 3.0 to 3.5 mm is a reasonable goal I would again use caution in just blindly following measurements taken from another guitar.

Sasquatch51

Post by Sasquatch51 » Thu Oct 05, 2006 3:09 am

Yeah, I looked at Kenny Hill's website, and he does mention doing that, but he also said that's not the way he does it. He does, however, use a straightedge from the top of the bridge saddle to the first fret. I think the measurements he gives are approximately representative of the measurements that most people use (without capoing), minus the difference that you would get from fretting at the first fret...for instance, he uses 2.7mm for the 1st string capoed at the first fret, where most people shoot for about 3mm (not capoed). I think that actually works out to about the same thing.

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Post by charlesivey » Thu Oct 05, 2006 4:24 am

Since every guitar can be different, I would like to add that some fine guitars may have 4 or 5 mm action height or more -- action is so complex because of the many variables, but also because some players like higher action and/or their guitars may simply sound better with higher action. Just be careful and make any adjustments with very small changes -- which has been well said above.

One thing to consider... if you keep lowering and lowering the action, there will be a time when, Oops... "Houston, we have a problem." I have had an older guitar lowered (by a luthier) but I was still very afraid that might have been a mistake -- turns out it wasn't, but the guitar did not play any easier or differently (well maybe it lost a slight amount of volume.)
CI

"Things should be made as simple as possible, but not any simpler" A. Einstein

Guitar Slim

Post by Guitar Slim » Thu Oct 05, 2006 6:31 am

Ronald Coates wrote:I wasn't try to be flipant. If I came across that way I apologize. I meant why would I care about hill's set up or anyone elses... In that you need to set up the guitar based on what you have in that specific guitar. Again sorry for any hostility that came across in my post. None intended.
No need at all to apologize. If anyone was being a smart alec it was me. I can get a little stressed and snippy sometimes at work, which is where I usually fire off these posts during breaks and the odd slow period.

Something has just occured to me. String height is something different from saddle height. String height is just what it is, taking into account all variables such as the height of the nut -- if it's 3.5mm at the 12 fret, 2mm at the 5th and >1mm at the first, it is what it is.

It seems what luthiers and techs like Hill and Erlewine are measuring is actually the saddle height, which theoretically a constant, although it does need to be measured against a second point, in this case the (somewhat arbitrary) top of 12th fret. It seems that when luthiers and techs measure a guitar's action, they're usually referring to the the saddle height, not the string height, and perhaps they perfer to do that because it is more constant. While our inclination as players is to just get out the rule and measure the string height. Does that make sense?

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