Maintaining Tuning Stability On Your Guitar
By Samuel Frazier
Machine heads
The first place most players look to when their guitar is not staying in tune seems to be the
tuning machines. This is to be expected, as they are what you adjust to tune your instrument. That
said, tuning machines are not the only factor that have an impact on tuning stability. In fact,
more times than not I have found that it is usually not the tuning machines causing the problem.
But they are certainly a logical place to start your problem solving. Here are some possible ways
that your tuning machines could be in need of attention:
- Tuning machines are slipping: If the tuning pegs cannot hold the strings at proper tension, the
strings will slowly go flat over time.
- Strings are not wound tightly: If stings are loosely wound around the tuning pegs, the tuning
will go flat as the strings are stretched, whether from simply playing your guitar or from string
bending.
- Tuning machines are not tightly mounted onto headstock: If the machines are free to move in
place on the headstock, tuning stability can be compromised.
As we can see, the first case is directly related to the condition of the machines, whereas
the last two cases can be addressed without the need to change out your machines.
Tuning machines are slipping
I will point out that the first case is the most infrequent that I have had to deal with as
most machines have their gear ratio set such that this does not happen. But then again, I play 0.01
to 0.046 gauge strings. The heavier gauge you play, the more tension will be exerted on the
machines. So, I will say that if this does happen, then you will likely need to replace the
machines with a fresh set capable of holding the tension of the strings. If possible, find out the
gear ratio of your current set and look for a new set with a higher greater ratio. This should fix
the problem.
Strings are not wound tightly
I find this to be the most common cause of tuning problems, but I also find it to be somewhat
self-correcting. Usually all that is required is a good stretching of your strings, and it usually
only happens when playing with a new set of strings. That is, when installing a new set of strings
there is almost always a bit of play between the strings coils and the tuning peg that it’s wrapped
around. The solution to this is to play and tune until the strings have stretched out and no longer
need frequent tuning. You can help the process along by tugging lightly on each string in an
outward motion (away from the sound hole or pickups) or by playing a lot of string bends.
Tuning machines are not tightly mounted onto headstock
For the third case, we can see that the simple solution is to tighten the machine mounts on
the headstock (after first making sure they are properly aligned.) In the case of either damaged
machine mounts or a damaged headstock, a larger effort may be required. At this point I would
consider consulting a professional.
Tuning machines (when correctly installed and paired with an appropriate set of strings)
really should only cause temporary problems, namely when there is a need to stretch in a new set of
strings. This brings me back to my earlier statement that, in most cases, tuning machines are not
the source of long-term tuning stability problems. So, let’s examine a few other possible causes.
The Nut (the most common source of problems)
Possibly one of the most overlooked causes of tuning stability problems is the nut. To
consider how the nut affects tuning stability, we simply need to think about the properties of “
sliding friction.” Consider the high tension on the strings and the slight angle that exists
between the headstock and the neck: that angle creates a downward force on the nut from the
strings. This force created between the nut and the strings gives rise to sliding friction. With
this friction there is created a range of unequal tensions that can be made across the nut. In
other words, the tension of the string over the fingerboard (correlated to the pitch you hear) need
not be equal to the tension of the strings behind the nut (over the headstock). So how does this
affect tuning stability, you ask?
First, let’s imagine that all strings are tuned to pitch and that, in this special case, the
tension is equal on both sides of the nut. You would then have the two following possibilities:
- You bend a string on the fingerboard >> the string goes flat upon return
- You bend a string behind the nut >> the string goes sharp upon return
With these two cases we can see that there is a change in the distribution of string tension
over the nut.
Bending on the fingerboard
In this case, the bending of a string on the fingerboard causes an increase in tension behind
the nut (it’s being pulled). However, with the range mentioned previously, we can then predict
that, once the string bend is released, not all of the tension will be evenly returned as it is now
distributed more heavily behind the nut. This causes there to be less tension on the fingerboard
side, and thus the string goes flat.
Bending behind the nut
In this case, the tension becomes more heavily distributed on the fingerboard side, and thus
the result is reversed. That is, now there is greater tension on the fingerboard side, resulting in
the stringing ringing sharp.
From these examples we can conclude there is one very simple technique to improve tuning
stability with regards to sliding tension on the nut:
-
Always tune your strings up to your target note, not down.
This works because, in the real world—where tension is not equal on either side of the nut—it
sets the higher end of the range of tension behind the nut and the lower end over the fingerboard.
The headstock side of the strings is therefore not as capable of storing more tension, and thus
after a string is bent over the fingerboard, it is more likely to return back to its original
tension instead of going flat.
Let it be noted that this technique works only on the basis that you do not bend strings
behind the nut during play (most people don’t). Also, this method will not work if you have (and
use) a tremolo during play, because once the tension is lessened on the fingerboard side by
depressing the tremolo bar, it returns the tension of the fingerboard side of the strings to the
upper end (tension behind nut is now at lower end.) Quite simply you can think of a whammy bar dive
bomb as being the opposite of a string bend, producing the opposite effect. Lastly, if the nut is
binding strongly (meaning there is a larger tension disparity than described above), this method
may not work well enough to solve all your problems. There are, however, ways to further address
the problem, including:
- Re-shaping the nut
- Applying a lubricant
Reshaping the nut
If you want to reshape the nut, I recommended that you take your guitar to a professional as
he/she will be able to do this, and more importantly, determine if it is even needed. And keep in
mind, some binding is normal as it is physically impossible to rid the nut of all friction.
Applying a lubricant
The second option is definitely recommendable as it is safe, inexpensive, and most of all, it
is pretty easy to do. I personally recommend using Big Bends Nut Sauce, which can be bought at your
local Sam Ash Music Store or from Sam Ash Direct. Some guitarists have been known to use a graphite
lubricant, but I find the Nut Sauce works much better, and oddly, I also find it is less messy. All
you have to do is place it into the grooves of the nut and then when the strings are replaced over
it, the pressure distributes the lubricant. The friction—and with it, the tension disparity—will
then be decreased.
Other possible causes
While usually correcting tuning stability at both the tuning machines and the nut solves most
problems, there are sometimes other possible causes of tuning problems. These situations are
generally rare with fixed-bridge guitars, and more common with tremolo-equipped guitars.
Fixed-bridge guitars
In the rare case of instability on a fixed-bridge guitar, the solution pretty much comes down
to either lubricating the saddles or replacing the saddles altogether. It is about as simple as
that, due to the simplicity of most fixed bridges.
Tremolo-equipped guitars
In the more likely case of tuning instability on a tremolo-equipped guitar, it is recommended
that you inspect the bridge for precision and accurate return. The most common reason for tuning
instability on a tremolo-equipped guitar (assuming that problems with the nut and machines have
been eliminated) is that the tremolo bridge is not returning back to its original position. This
can be caused by misalignment in bridge posts to knife-edges or, quite simply, just the friction
within the bridge overall. A re-alignment and lubricant of some kind can sometimes solve the
problem, assuming that the bridge posts and knife-edges are not damaged.
One last note
It is important that you diagnose tuning problems on a guitar equipped with fairly new
strings. Brand new strings need to be stretched in first, and old strings do not hold tuning well
for many reasons not addressed here. Therefore, your best bet is to diagnose your problems with a
set of strings that have been stretched in, but which are still fresh.
Samuel Frazier is a full-time student studying Physics at North Carolina State University and
living in Wake Forest, NC. He is a self-taught guitarist who plays by ear only and has been playing
for 12 years. He says his favorite styles of music are rock and metal. Samuel and his family shop
at the Sam Ash Music Store in Raleigh, NC. You can reach him at: smufrazier@gmail.com
This article was submitted by a reader. If you have an idea for an article that will be
interesting to other musicians, amateur or professional, we invite you to submit it to us.
We will pay you $50 cash if we publish your article and will issue a prize for the best
article submitted each calendar quarter. At your request, if we publish the article,
we will include your name and e-mail address as
a “by-line.”
More details here
