Jean Larrivée Guitars USA Inc. | Guitar Care & Maintenance
Care & Maintenance
Very few people really understand the care required by a high-end
instrument (a category which all Larrivee Guitars fall into). The way you care
for your instrument greatly affects its appearance, sound, and length of its
life. With proper care a new guitar will last for more than a century.
A solid wood acoustic guitar is made from thin pieces of wood (under 1/8th
of an inch thick); and because the wood is so thin it has a great deal of
surface area and therefore it both gains and loses moisture very quickly.
When wood loses moisture - it shrinks.
When wood gains moisture - it expands.
This expansion and contraction in relation to relative humidity, is at the root
of the majority of problems you will see in an acoustic guitar. The average
guitar is built between 40-45% humidity, relative to 72 degrees Fahrenheit
(22 Celsius) better known as room temperature.
Relative Humidity
What is Relative Humidity and why is it not just called humidity? Here is a
layman’s summary of this scientific technical term: The amount of moisture
that air can hold changes based on temperature. The warmer the air gets,
the more moisture it can hold.
This means that 50% humidity at 90 degrees is different from 50% humidity
at 20 degrees. Since the humidity level is relative to temperature, the
humidity at a given temperature is expressed as “Relative Humidity”. In
this document when we talk about relative humidity we will presume a
temperature of 72 degrees.
The safe Relative Humidity levels for a solid wood acoustic guitar can range
from about 0-5% below to 10-15% above the relative humidity under which
it was built. Once the guitar is brought outside of this range, the guitar
begins expanding or contracting. Dehydration accounts for about 90% of
climate based repairs.
Jean Larrivée Guitars USA Inc. | Guitar Care & Maintenance
Humidity Range Guide
Use the following guide to see the healthy zone and damage that
can occur outside of the normal humidity range.
RELATIVE HUMIDITY
90-100%
85-90%
1-3 Days Exposure
3+ Days Exposure
Guitar body will appear swollen and
sound quality will be diminished,
playability will decrease. Back
braces may come unglued as the
wood expands. Action will get very
high quickly.
All Glue Joints will loosen, Top and Back braces will
loosen. Bridge may shear come off the top, the
guitar top will expand and belly (become convex)
both in front of and behind bridge, if the glue joints
do not delaminate then the guitar will be unplayable.
Fretboard from the 14th on will appear raised.
Mildew may form inside the guitar. Guitar will very
likely de-construct itself.
Guitar body may appear swollen,
sound quality will slightly diminish,
playability may decrease. Action will
become higher.
Braces will come loose after a few weeks, top and
back will appear very bellied (convex), bridge may
loosen or come off, playability will be affected.
Fretboard from the 14th on will appear raised.
Mildew may form inside the guitar.
Sound quality may be diminished.
Soundboard may appear swollen.
Action may be slightly high.
Top and back will appear bellied (convex), playability
will be affected. Fretboard from the 14th on may
appear raised. Guitar will start to have a musty smell
after a couple of months.
No major problems should occur
with limited exposure.
Top and back will appear bellied (convex), playability
will be affected. Fretboard from the 14th on may
appear raised. Guitar will start to have a musty smell
after a couple of months.
No problem will occur in this range.
No problem will occur in this range.
70-85%
55-70%
42-55%
Continued...
Jean Larrivée Guitars USA Inc. | Guitar Care & Maintenance
Humidity Range Guide
RELATIVE HUMIDITY
1-3 Days Exposure
3+ Days Exposure
No major problems should occur
with limited exposure.
Fret ends may feel sharp, soundboard may appear
slightly collapsed (concave), action may lower
slightly, bridge wings will appear concave, the guitar
may develop a buzz.
Fret ends may start to feel sharp,
top may become slightly collapsed
(concave).
Fret Ends will feel sharp, Soundboard and back will
become flat or collapsed (concave), action will feel
lower, guitar will likely buzz, Bridge wings will appear
concave, after several months the bridge may “lift” or
shear off.
Frets will feel sharp, top may begin
to collapse (concave), Action will
lower very quickly, guitar may
develop a buzz.
Fret Ends will likely feel very sharp, Soundboard and
back will become flat or collapsed (concave), last six
frets of the fingerboard will likely sink into sound
hole, the action will lower, and guitar will buzz, the
Bridge wings will appear concave, cracks in the
soundboard may develop especially from the bridge
to the butt of the instrument, the bridge may shear
off (come unglued).
Frets will likely feel sharp, top and
back will likely become collapsed
(concave), Action will lower very
quickly, guitar will likely develop a
buzz. Soundboard may develop a
crack running from the bridge to the
butt, bridge may come unglued.
Fret Ends will feel very sharp, Soundboard and
back will be collapsed (concave), last six frets of
the fingerboard will sink into sound hole, action
will be lower, and guitar will buzz, Bridge wings will
appear concave, a large crack in the soundboard
will likely develop from the bridge to the butt of
the instrument, and the bridge may come unglued.
Rosette rings and tail wedge may be visibly raised.
Frets will feel sharp, top and back
will become collapsed (concave),
Action will lower very quickly,
and guitar will develop a buzz.
Soundboard may develop cracks
especially running from the bridge
to the butt, bridge may shear off.
Fret Ends will feel very sharp, Soundboard and back
will become collapsed (concave), last six frets of the
fingerboard will sink into sound hole, the action
will be extremely low with buzzes up and down the
fingerboard, the Bridge wings will appear concave,
cracks will develop in the soundboard especially
from the bridge to the butt of the instrument, and
the bridge will shear off. Rosette rings and tail wedge
will appear raised. Braces which do not shear off
may push out the binding of the instrument Braces
will be visible as high spots on the top and back.
35-42%
25-35%
20-25%
10-20%
0-10%
Jean Larrivée Guitars USA Inc. | Guitar Care & Maintenance
Care & Maintenance
As you can see, a great deal of damage can occur to an instrument that is
brought outside of the healthy relative humidity range. It is important to
take proper care of your instrument following the guidelines in the following
sections.
Many people believe, if a guitar is worth several thousand dollars that
it should not be affected by the problems associated with fluctuations
in relative humidity. The truth is that high end guitars in general
areMORE sensitive to humidity change than others. A high-end guitar
is constructedusing thinnerwoods and thinner finishes whichare more
susceptible to climate change than guitars constructed of laminates.
Summer Care
Although the woods we use in your guitar’s construction are stable and aged
three to five years, after assemblage the glued joints of lining, purfling, etc.,
can take up to a year to stabilize. With the introduction of excess moisture
(in the form of high summertime humidity), the guitar will expand (and
distort) unless properly cared for. Damage to the instrument may result.
When the relative humidity exceeds 60%, the guitar will begin to expand.
Following are a few symptoms of this expansion which you would observe:
1) The easiest symptom to spot is the bellying of a guitar top. Most
commonly the top will begin to raise (or swell), which appears as a
distortion of the surface of the top. This is especially noticeable on the
cutaway models. The back of the guitar will also raise (swell) and distort
under these conditions, as evidenced by a depression in the back, at
the front, and tail blocks. The higher the relative humidity, the more
noticeable the distortion becomes. You can check this on your guitar
by removing your strings and placing a straightedge across the top
between the soundhole and the bridge (running from the bass to treble
side). Under normal circumstances, the top should be flat or just slightly
convex (about 1/32” or 1mm gap on either edge of the ruler. Any more
and the guitar is considered bellied.
Jean Larrivée Guitars USA Inc. | Guitar Care & Maintenance
Care & Maintenance
2)Another visible change with the introduction of excess moisture is that all glued
joints, e.g. the back, top and side joints, will appear much more noticeable.
This is especially evident around the inlays. The pearl is all but impervious to
changes in humidity, but the wood into which the pearl is inlaid is soft and
swells under conditions of high relative humidity. As the wood swells, you will
detect a line surrounding the inlay where the moisture enters the wood.
3)A rise in the height of the action is one of the major problems to be observed
in guitars exposed to excessive relative humidity. The more moisture, the more
pronounced the height of the action becomes. This problem is particularly
evidenced in very moist climates like Hawaii, Florida, or Japan. This rise in
“action” is caused by a number of forces. The excess moisture causes the top
of the guitar to swell and “belly” outwards, pushing the bridge and the strings,
upwards. The back of the guitar also expands. As the back does so, it pushes
the neck upwards. This has the effect of making the area between the nut and
saddle somewhat concave.
4)The problem is then further intensified by the expansion of the ebony
fingerboard which causes the frets to loosen. These frets, when fitted, are tight
and serve the function of keeping the neck back. When they loosen due to
expansion of the fretboard, the neck will also bow upwards causing the action
to increase to an even greater degree.
Please keep in mind that the finish will not stop the moisture from entering,
though it may slow it down for three or four days. With longer exposure to higher
relative humidity, the finish will begin to distort. This distortion in the finish on the
top appears as small ridges, lending a somewhat corrugated appearance. On the
back and sides of your guitar it will appear as though the pores are sinking. As the
rosewood expands, the pores also enlarge, causing the finish (which is impervious
to humidity) to sink deeper into the pores. The finish on the mahogany of the neck
will also appear to have sunk into the pores for the same reason as the back and
sides.
Lastly, one more annoying effect of high relative humidity on the guitar is the loss
of sound quality as the instrument distorts, coupled with a definite decrease in
the string life. Happily, all of the above problems associated with exposure to high
relative humidity should correct themselves when the instrument returns to the
normal range of humidity: 40% to 50% relative to 22°C or 72°F.
Jean Larrivée Guitars USA Inc. | Guitar Care & Maintenance
Care & Maintenance
There are more serious effects of prolonged exposure to high humidity, including
loosening of the braces, stretch marks in the finish, an action which stubbornly
remains high and a general loss of appeal in the guitar. While these problems can
usually be handled by a competent repair person, they may leave indelible marks
on the guitar.
Please note that damage of this kind is not covered by warranty.
Now here is the good news. Most of the problems related to excess humidity can
be avoided with some simple precautions.
1)Keep your guitar out of the case. A guitar stand is a good idea as it allows the
air to circulate around your guitar. If possible, it’s a good idea to keep your
guitar on the second or third floor of your house when the weather is warm.
2)Never keep your guitar in a dark cool basement during periods of high
humidity. Do not store it inside its case in such an environment as the moisture
accumulates in the tight quarters of the case.
3)If the humidity in your home is constantly about 70% then considering
investing in a dehumidifier. You can also use chemical desiccants, but it lacks
the convenience and easy of the “set-it-and-forget-it” dehumidifiers.
Another factor which can adversely affect your instrument in the summertime is
high temperature. When the weather is warm, never leave your guitar in the trunk
or back of your car. In such locations, the build-up of heat can exceed 66°C or
150°F. Temperatures this high can have a devastating effect on your guitar, as the
heat can cause the glue joints to melt. A guitar is built using standard carpenter’s
glue. Heat destroys this glue. Your guitar can actually come apart on itself. With the
loosening of the fingerboard under these conditions, the action will become very
high. Please note that this problem will not correct itself when the temperature
drops to normal, and to lower the action in this case would require major repair
work which would not be covered by your warranty.
Spruce tops contain small resin pockets not too visible to the eye under normal
conditions. This is especially true of tight grained spruce and is more common to
German Spruce than to domestic spruce. When the environmental temperature
increases dramatically, it causes these resins to expand and to try to escape. Of
course the only way out is through the finish causing blemishes all over the top.
Jean Larrivée Guitars USA Inc. | Guitar Care & Maintenance
Care & Maintenance
Although this looks disastrous, it is not particularly hard to repair. A competent
repair person can correct this problem with a light sanding and polishing of the
top. This kind of damage is not covered by your warranty as it is caused exclusively
by exposure of the instrument to excessive heat.
One more problem worth mentioning here in regard to summer is that if the guitar
is exposed to bright sunlight for a period of time, a premature yellowing of the
top will occur. Imagine getting a tan. This yellowing is not in itself a problem, but
if there is some obstruction to the light, say a guitar strap laying across the face of
the guitar, it will leave a lighter print in the shape of the obstruction which would
be quite a defacement. This is one thing to keep in mind when you put your guitar
down during the summer months.
We do not recommend the use of any oil, silicon or wax product on the
fingerboard. With regular playing the oils from your fingers are more than
sufficient (‘to condition the wood”), and the fingerboard should not crack.
To lengthen the life of your guitar strings, simply wipe the strings down with a soft
cloth after you play. When changing strings, it is a good idea in both summer and
winter to go over the fretboard with 000 Steel Wood (make sure you take care not
to scratch the finish on top), removing all build-up of oils, dirt, dust and grime. The
steel wool will also serve the function of slightly polishing the frets and fingerboard
which makes them more slippery and results in an overall improvement in
playability.
Winter
Winter is when your guitar can be in real peril. The danger in winter is excessively
low relative humidity, i.e. lower than 40% relative to 22°C or 72°F. Exposure at
any rate lower than 40% for any period of time will result in damage. Damage
caused by dryness is much more serious than the damage associated with excess
humidity, and usually requires the prompt attention of a competent repair person.
A hygrometer (available at most hardware stores) will give a rough estimate of the
humidity, though they are notoriously inaccurate. Still, they are better than having
no idea of the fluctuations in humidity surrounding your guitar.
Watch your instrument, it will tell you when it is dehydrated.
Jean Larrivée Guitars USA Inc. | Guitar Care & Maintenance
Care & Maintenance
You can examine your own guitar for the following symptoms to determine if your
guitar is dry.
1)Sharp Fret Ends – Sharp fret ends are perhaps the first symptom that your
guitar is drying out. The ebony on your fretboard shrinks, but the metal
fret wire does not. This causes the frets to protrude from the edge of the
fingerboard. You’ll notice this while playing your guitar, as the frets feel sharp.
Some shrinkage of the fingerboard is normal over the life of the guitar, and
is not a sign to panic. However; if you notice it then you should examine the
guitar for additional dehydration symptoms.
2)Collapsed Top – When a guitar dries out the normally convex top will collapse
and become concave. You can spot this quite easily by either sighting across
your soundboard (between the soundhole and bridge) or by laying a straight
edge across this area. Under normal circumstances the top should be flat or
just slightly convex (about 1/32” or 1mm gap on either edge of the ruler). If
your straight-edge sits flat on the soundboard or if there is a hollow, then your
soundboard is considered collapsed.
Note the gap under the straight edge showing the collapsed soundboard.
Jean Larrivée Guitars USA Inc. | Guitar Care & Maintenance
Care & Maintenance
3)Concave Bridge Wings – If you sight across the soundboard of your instrument
from the base side to the treble side, you might notice that the bridge wings
appear cupped or concave. If you notice this, it is a sign that the guitar has
been dried out at some point. This symptom usually does not go away with
rehydration.
4)Suddenly lower action / new buzz & Bad Neck Angles – As the guitar dries out,
the soundboard and back collapse. This causes the bridge to lower and the
neck to pull backwards. When this happens, the strings are brought closer to
the fingerboard. This has the effect of lowering your action and likely creating
a buzz. If a buzz has suddenly developed, then check for other dehydration
symptoms. Believe it or not, many people who think they have bad neck angles
are just in need of some proper humidification.
This is a shot of the back of the guitar, with a straightedge laying across
the waist. This should normally be bellied or convex, but this guitar is so
dry, it has become concave.
Jean Larrivée Guitars USA Inc. | Guitar Care & Maintenance
Care & Maintenance
5)Corrugated Soundboard – Normally, the finish of your instrument will appear
flat. When the guitar dries out, the soft wood area between the grain lines on
your soundboard shrinks. This creates a corrugated look to your soundboard.
Corrugation and distortion in the soundboard of a dehydrated guitar.
Jean Larrivée Guitars USA Inc. | Guitar Care & Maintenance
Care & Maintenance
4)Fretboard sinkage into Soundhole: When the top collapses - See #2 above - the
end of the fretboard is pulled down into the Soundhole. This has the effect of
creating a hump at the 14th fret and creating nasty buzzes. The picture below
shows a good (or bad depending how you look at it) example of this problem.
See how the end of the fretboard is sinking into the soundhole? See the gap
under the fingerboard by the side dot? All caused by very low humidity.
Jean Larrivée Guitars USA Inc. | Guitar Care & Maintenance
Care & Maintenance
5)Cracked soundboard or back – This is a clear sign that the guitar has been
dried out. When the tension in the top (created by shrinkage) has built up, it
eventually releases - and it releases in the form of a crack. Nine times out of
ten the first crack will appear under the bridge, running from bridge to butt,
usually on or close to the center seam, and often appear within the center six
inches of the top.
Jean Larrivée Guitars USA Inc. | Guitar Care & Maintenance
Care & Maintenance
The extremely low temperatures of winter in some climates also pose a danger
to your guitar. Exposure to extreme cold is mainly detrimental to the finish of
your guitar and varnish checking (small cracks in the varnish) is common where
temperatures drop below the freezing point. While the finish used on today’s
Larrivée guitars is much more resistant to this problem than traditional lacquers,
common sense is still advised. The problem most commonly occurs when you have
your guitar outside in below freezing weather for more than15 or 20 minutes, for
example, walking home with your guitar, then immediately upon coming into a
warm room, open the case to remove your guitar. Conversely, taking your guitar
from a warm home out into an extremely low temperature may cause problems.
The solution to this problem is prevention. Allow your guitar to cool or warm up
gradually with case closed for at least one hour. If possible, try not to take your
guitar out in extremely frigid temperatures.
If, in spite of your best efforts, the finish on your guitar has checked, take heart.
Although the checking is permanent, it will not affect the life of the guitar or its
playability or sound. It affects only the appearance.
To correct varnish checking would require a costly refinishing job which, on top
of not being covered by your warranty, could drastically affect the sound of the
instrument. Our recommendation would be to learn to live with the checks.
Another wintertime problem in relation to low humidity is the lifting of the bridge.
Once more, the underlying cause is shrinkage of the soundboard. The bridge’s
grain runs perpendicular to the grain of the soundboard and does not shrink in the
same direction as the top, therefore separating from the top with a shearing action.
This is easily repaired by a competent repair person. Believe it or not, the lifting of
the bridge is actually desirable as it often prevents the cracking of the soundboard
(A much more damaging issue).
The same sort of tension can occur as the woods of the back and soundboard
shrink against the struts and a shearing action may cause them to separate. The
result is internal buzzing and a structural weakening of the guitar. Repair of this
problem can become quite costly and is not recovered by warranty.
The avoidance of most of these winter problems requires only the use of a little
common sense. Follow some of these simple steps to keep your guitar safe:
Jean Larrivée Guitars USA Inc. | Guitar Care & Maintenance
Care & Maintenance
1)Invest in a hygrometer – You can get a hygrometer at most hardware stores
for a few dollars. This helps you keep tabs on the Humidity level in your guitar
storage area.
2)Invest in a Room Humidifier – We personally believe that it’s best to humidify
the room that the guitar is kept in, not just the guitar. Many people use only the
small Soundhole humidifiers, and while these units do work they contain only
a small amount of water and can be totally evaporated within the first eight
hours. These units should be checked and filled accordingly every day in areas
of extreme cold and low humidity. It is very easy to set-and-forget the room
humidifier and you can easily tell when it is low on water as most of them have
clear reservoirs.
3)Radiant Floor Heating – Is VERY bad. If you have radiant heating (hot water
which runs through the floor) get your guitar off the ground. The built-up heat
can DESTROY your guitar in very short order.
4)Keep your Guitar Cased – Never Leave your guitar hanging on the wall in
winter. The heat from your furnace rises and the temperature at floor level
may be 18°C, five feet off the floor it may be 22°C, and eight feet off the
floor 27°C, and at that extreme temperature the relative humidity becomes
extremely low.
If you have concerns about humidity, or you don’t quite understand the
information here, feel free to contact us and we can help walk you through
the basics.