The
Care and Feeding of Your Acoustic Guitar
Presented by
Martin Guitars
Proper Care of Your Guitar
Humidity, Temperature, and Storage
Your guitar is made of
thin wood which is easily affected by temperature and humidity. This
combination is the most important single part of your guitar's surroundings.
Martin keeps its factory at a constant 45-55 percent humidity and 72-77
degrees Fahrenheit. If either humidity or temperature get far away from
these factory conditions, your guitar is in danger. A rapid change in
temperature or exposure to cold can cause small cracks in the finish. These
are lacquer checks. We recommend the use of a hygrometer/thermometer to
measure the relative humidity and temperature surrounding your guitar.
As humidity increases, moisture content of wood goes up rapidly, causing it
to expand and swell. A gradual increase in humidity won't generally do
permanent damage to your instrument. When very high humidity is combined
with high temperature, glue joints could possibly become weakened and may
even open slightly. If your guitar is exposed to high temperature or
humidity for any length of time, the glue under the bridge could weaken
causing the bridge to pull off.
Rapid changes in local humidity are what you want to guard against. If, for
instance, you place your guitar near a source of dry heat, the humidity
around it will drop much faster than it would naturally, although a sudden
dry spell can have the same effect. If the moisture tent of wood is forced
down in a hurry, portions of it shrink faster than others, causing cracks
and open joints. Don't set your instrument next to a source of heat or hang
it on a wall where it will dry out. At all costs, avoid hanging your guitar
on an outside wall during winter months. The wall will be cooler than the
inside air. The result is a conflict between the temperature of the top and
back, with potential damage as a result.
Should the guitar be exposed to freezing temperatures, let it warm to room
temperature while still in its case. This lets it come up to room
temperature more slowly, decreasing the possibility of wood and finish
cracks.
Caution should be taken if you choose to use a humidifier to combat low
humidity. Moisture in direct contact with the guitar could cause damage, as
can the rubber or vinyl parts of a humidifier.
We recommend storing your guitar in its case when not in use. Humidity is
easier to control in a smaller space. Don't bother loosening the strings
when putting your guitar away unless it won't be used again for several
months. Constantly tightening and loosening strings quickly ruins their
sound.
The Martin hard case supports the neck and body of your guitar as evenly as
possible. It's important that you don't let anything lie under the head (the
tuning machine end), as this could damage the neck and body.
Repairs to your instrument should be performed by an authorized repair
person.
Cleaning the
Finish
The best way to clean your guitar is with a warm, damp cloth. This will
remove harmful chemicals. Your guitar is coated in the highest-grade finish
available and is sensitive. Any type of solvent, especially those found in
plastic, vinyl and leather straps, will mar the finish, as will alcohol,
citric acid, aftershave lotion, insect repellent, and a number of related
substances. Perspiration can also damage your guitar, so keep it dry. To
polish it, use the special Martin polish and a clean Martin polishing cloth.
We recommend wiping down your instrument and strings with a soft, dry cloth
before storing to remove harmful skin oils. Products containing silicone
should not be used.
Tuning Machine
Maintenance
Tuning machines normally need very little care other than periodic
lubrication. Enclosed machines, the type with a cover over the gears, are
lubricated by the manufacturer, but the open type should be lubricated once
or twice a year. Just put a little household petroleum jelly on the end of a
toothpick and place the jelly in the gears. Be careful not to use too much
because it catches dust which can wear out the machines.
Some types of machines are adjustable for ease of tuning. The open type can
be made harder to turn by tightening the screw in the middle of the gear.
Check this screw every time you replace the strings because it can work
loose. Most enclosed machines have a screw in the end of the tuning knob
that will make the machines harder to turn when the screw is tightened. Not
much tension is needed, so don't overtighten the adjusting screws.
Inserting the
Bridge and Endpins
The strings are held in place at the bridge by a small notch at the front of
each bridge pin. It is important that the pin slot be facing straight
forward so the string is properly aligned on the bridge saddle. Make sure
that the ball end of the string is pulled up tightly against the inside of
the top before inserting the bridge pin.
Too often bridge pins are hammered in so hard that they become wedged and
split the bridge. After inserting the string and pin, a solid push with your
thumb is all that is needed.
The endpin is tapered and is wedged into the bottom end of the guitar. It is
not glued in. It should be checked frequently to make sure it has not worked
loose.
Strings
Different styles of playing demand different types of strings; but, unless
you are a specialist in a particular style, your guitar came with strings
that will normally give the best results. You may want to make your guitar
easier to play and use one of our lighter string sets, but your bridge
saddle and neck may have to be adjusted to prevent fret buzz. A classical
guitar has much lighter bracing than the usual steel-string acoustic guitar,
and using steel strings on it will literally pull it apart.
Strings don't last forever. As you play your guitar, you will notice its sound will gradually lose brilliance. It will begin to sound slightly muffled because the strings have begun to wear out. Human skin moisture causes strings to become dirty and corrode, and this layer of corrosion eventually deadens the sound of the strings. At this point, the entire set should be replaced. Replacing only one string causes an unbalanced sound.
* MARTIN 6-STRING GUITARS ARE MADE FOR STRINGS NO HEAVIER THAN MEDIUM GAUGE, AND 12-STRING GUITARS SHOULD HAVE A LIGHTER GAUGE.
Adjusting the Action
Often as a guitar ages, it seems to get harder to play. This is because the
height of the strings above the fingerboard has increased slightly. This
height, usually called "action," is very important to the playability of the
instrument. However, if the strings are too low, they will buzz against the
frets. The action can be adjusted at the bridge and saddle by an authorized
repair person.
The adjustable neck rod is not for action adjustments; it is to be used to
obtain the proper neck relief and should also be performed by an authorized
repair person. Though straightening will have an effect, the neck should not
be adjusted if it is already in proper alignment.
Necks and Tops
Neck bow itself is often misunderstood and talked about as if it is the
worst thing that can happen to a guitar. For some playing styles, a slight
forward bow can prevent buzzes. With the adjustable neck rod, the neck can
be adjusted for relative straightness. This is not considered to be a
consumer adjustment and should be made by properly equipped Martin
authorized distributors.
Sometimes sighting down the neck gives the illusion of neck bow when it is
actually within specifications. This is because the top will rise and fall
with changes in temperature and humidity. This swelling raises the end of
the fingerboard, which is actually attached to the top rather than the neck.
If this should become too high, it might need adjustment or repair.
The bellying of the top is normal and should be expected. The top is
actually made with an arch. This will increase over a period of time due to
string stress and/or high humidity. Heavy-gauge strings should not be used.
If the bellying becomes excessive, the saddle and bridge may need to be
lowered to improve the playability.
Guitar Care
While Traveling
The guitar probably travels more than any other musical instrument in the
world, and it'll only be a matter of time before you take yours on its first
trip. If you're going to take your guitar on the road with you, remember,
it's not just another piece of baggage. You have to make an effort to
protect it.
If you're traveling by car, don't make your guitar ride in the trunk. It's
much safer in the back seat because most car trunks are neither heated nor
ventilated, so the temperatures can fluctuate wildly. Freezing or
overheating your guitar is an invitation for a crack or warp to occur. Your
guitar is assembled with glues that can be affected by heat causing
breakdown and loosening of glue adhesion. Most commonly affected is the
bridge.
Air travel has become the most popular mode of commercial transportation,
but protection of your instrument is important. Airlines don't set out to
damage guitars intentionally, but a conveyor system can't tell a guitar from
other baggage. Airlines may consider a guitar to be too fragile for their
handling and may require that a waiver be signed which limits or removes
their liability. Don't sign such a document if you can avoid it. Even a hard
case can't always protect a guitar from damage from mishandling by
individuals or commercial carriers.
Occasionally you can bypass the usual baggage handling system by asking to
take your guitar to the boarding area where it can be tagged and hand
carried to the airplane. Upon arrival, notify the flight attendant or
customer service representative and try to retrieve it at the gate. Not all
air-lines give you this option.
There are size restrictions on carry-on luggage. It must fit in the overhead
bin or under the seat ahead of you. Some flight attendants may allow you to
try the overhead bin, but if it doesn't fit, it may have to be checked as
baggage. Loosening the strings and using a soft cotton packing material to
keep the guitar tight in its case will decrease the possibility of damage
while a guitar is in the baggage compartment. Martin's hard case will help,
but a good case is not a cure-all for careless handling or accidents.
Using Guitar
Straps
Your C.F. Martin instrument is coated with multiple thin layers of
high-grade finish. Our finish can be adversely affected by interaction with
certain synthetic straps and can also be affected by leather straps.
Vinyl and synthetic leathers contain solvents that keep the material soft
and supple. These solvents will transfer to the instrument's finish and
cause damage. Do not allow such straps to contact the finish. The best
procedure is to always remove your strap from your guitar after use and
store separately. Vinyl sofas, chairs, etc. should also be avoided.
* CAUTION: DAMAGE COULD BE INCURRED FROM PROLONGED CONTACT OF A MARTIN GUITAR WITH ANY STRAP. THIS APPLIES ALSO TO CONTACT WITH ANY OTHER VINYL OR SYNTHETIC MATERIALS, CAPOS, ACCESSORIES, FURNITURE, OR OTHER PRODUCTS.
How to String a Steel-String Guitar
![]() |
Insert each
string in its proper hole in the bridge. Keep the heaviest portion of the double winding facing away from the soundhole. |
![]() |
The string should be positioned with the bridge pin notch facing the string |
![]() |
The strings are
held in place at the bridge by a small notch in the front edge of each
bridge pin. Make sure that the ball end of the string is pulled tightly up against the inside of the top before inserting the bridge pin. Older Martin guitars may have small slots in the front of the bridge pin holes, but these are no longer necessary with the new style bridge pins. After inserting the string and pin, a firm push with your thumb on the pin is all that is needed to keep in place. The tension of the string and the proper positioning of the slot in the bridge pin will hold the saddle in place and the strings in proper alignment. |
![]() |
You might
occasionally encounter an older guitar with a thin bridge or a string
with a longer double winding adjacent to the ball end. Shown above is an old luthier's trick or remedy. An extra ball from an old string is placed over the string and drawn against the first ball. This will effectively back the string into the bridge, removing the heavy area of the string from direct saddle contact. |
Stringing a Solid Headstock
![]() |
The string is passed through the string hole near the top of the tuning machine post. |
![]() |
After coming through the string hole, the string is wound one-half way around the tuning machine post. Clockwise for the three bass strings; counterclockwise for the three treble strings. |
![]() |
After passing under the longer part of the string, the short portion is bent back over it. This will prevent string slippage. |
![]() |
After the
string is brought up to pitch (standard tuning), it may be clipped
flush with the top of the tuning machine post. Note that a string should pass around the shaft at least one full time. Windings should be under the previous one, or closer to the base of the shaft. |
Stringing a Slotted Headstock
![]() |
The string is passed through the tuning machine slot from front to rear. |
![]() |
The string is
brought around the under side and back to the front. Be careful not to drag the string across the surface of the headplate, you may accidentally etch the finish. |
![]() |
The end is
brought around the string and pulled back toward the end of the
headstock. This establishes a lock which will prevent slippage. Note that when the string is tightened the 'lock' will hold in place. |
![]() |
When brought up
to standard pitch, there should be at least two full windings on the
shaft. The end of the string may be cut off. We recommend leaving them at a length of 1/8", drawn through to the back for the neatest appearance. |
Parts of a Guitar