"The Charango is a very delicate musical instrument . Its enemy N° 1 is humidity.   The top plate of the instrument is very thin, and therefore very sensitive to climatic changes.
 
A Charango always kept in a box or rigid case will protect it from shocks and aggressions of climate. Assure that the materials used in the interior of the case are not of synthetic materials.

Extreme humidity or dryness is t very adverse to the charango. Excessive humidity produces a "swelling ", that disfigures and debilitates the wood.
Wood is an extremely hygroscopic material. That is to say it loses or it takes water to maintain a balance with the atmosphere . This must be always kept in mind when tryint to save our instrument of the variations of   the ambient humidity.
 
Charangos in musical use never must be hung on the wall since walls absorb and usually transmit the humidity. If the humidity is excessive it could soften the glues , the wood can yield, producing cracks (gaps?) in the instrument and even bends. Within the body of the charango can be accumulated dust that absorbs the humidity and affects the sound. This may be teliminated through the hole with a vacuum cleaner.

When charango is going to be a long time without being used , it is necessary to relax the cords completely and to maintain kept it in a rigid case . Dos not use covers, they are do not provide protection of the instrument.
 
DO not expose a charango in its case to the sun or the heat for prolonged periods of time. It can reach very high temperatures and   suffer irreparable damages.
 
If any accident tdoes happen to a charango, loosen the strings uit can be taken to la uthier.
 
The loudness of the stringed instruments depends to a great extent on the dryness of the wood of which they are made, which increases with the passage of time. Therefore, charango old, or conserved, can be transformed into a piece of inestimable value, still more if his constructor is not active or has died.
 
Never put a charango on furniture, chairs or never on the ground. Charango by its size is easy to knock or step on. It is a very fragile and recent instrument greatly with the blows. When it is not in the case, keep it in a papoose.
 
 
   
The simplest way to take care of the finish of acharango is to clean with a smooth a cotton closth after each use, this will avoid the accumulation of impurities and acids from the skin andwill maintain the brilliance of the finish for long time. The simplest, reliable universal cleaner is water. Slightly damp cotton can restore a brightness that has gotten to be dirty and opaque .  

Do not use alcohol, as it could ruin the original varnish. Be careful when cleaning using furniture polish. Make sure that it has been developed to clean and to revive the natural varnish of your charango. Avoid contact of plish with the strings
There are special liquids to clean stringed instruments, (guitar, violin, etc) that are perfectly applicable to charango.

The strings must always maintain the same tension, which makes more precise sound and fingering. With time nylon loses its tension and it thus it becomes necessary to change them periodically. This also will depend on the use the instrument.

The first strings are exposed to a greater wearing down, by the thin thing that are, and being more used. It is necessary to change them at least twice as often as the others

If you are changing all the strings it is essential to exchange old for new in turn and avoid releasing the tension from the bridge.

One   of the most delicate parts of l charango is the fretboard since it is not varnished and therefore the wood is more sensitive to deterioration than the rest of the instrument. Insufficient care of this aspect can cause that the neck bends   varying the height of the strings and therefore the pitch of the strings. The Charango becomes hard and vague. Naturally we are speaking of millimetric movements, but that any charanguista notices by touch. Avoid striking it , Do not use metal strings. Always be prudent employ recognized brands of string, to make sure that charango will be put under of the requisite tension , avoiding thereby a premature bending of the neck. "
 

Héctor Soto
 

[This message has been edited by Adrian Freed (edited September 10, 2003).]

I agree with your dry climate theory. Hmmmm....maybe higher altitude causes slower oxidation of the wood...

Then there is the issue of the sound waves being emitted upside down whenever the charango is north of the equator. Research needs to be done!!!

Everyone should know that if you install a Tachyon Flux Generator in the area you keep your charango, the upside down hemispheric waves - (UDHW) are generally neutralized.