Fine Classical guitars are made more fragile than factory made classical guitars and much more fragile than any steel string guitar, the reason to this is that classical guitars that are made to be concert instruments (to sound as loud and as good as possible) are designed to maximize the vibration of the top induced by the strings, The thinner the top is the more it responds to the strings vibrations. If you get at very thick top with heavy bracing it would sound very quiet and have a dull tone. Unfortunately the more fragile the top is the more susceptible it is to temperature and humidity variations and will expand or contract according to this variables.
Humidity and Temperature
Cervantes guitars keeps its shop at 45-55 humidity and a 70 -75 temperature
The ideal humidity for wood instruments is between 45 and 55 percent, above 65 percent the instrument begins to lose its brightest and will sound dull, the tone will lack definition and will diminish its overtone response and sustain. If it drops below 40 percent the guitar runs the risk of the body cracking the neck warping, joints separation, varnish cracking and delamination.
Also a rapid change in temperature or exposure to cold can cause small cracks in the finish. These are called lacquer checks.
Do not place the guitar near an open window where sunlight can heat it up. Don’t place it near a heater or air conditioner source,
If you place your guitar near a source of dry heat, the humidity around it will drop much faster than it would naturally, If the moisture content of wood is forced out to fast, portions of the wood will shrink faster than others, causing cracks and open joints
If the guitar is exposed to cold temperatures for a long period of time, allow at least an hour for the guitar to warm up to room temperature inside the case before taking the guitar out. Other ways the sudden changes in temperature may cause the finish or the wood to crack.
Don’t leave the guitar in a parked car during any season of the year. If you do, the heat or cold may damage it beyond repair.
If humidity increases, moisture content of wood goes up rapidly, causing its woods to expand and swell. When the humidity is very high along with high temperature, glue joints could become weakened and may slightly open. If this high temperature and humidity prolong over time the glue under the bridge would weaken causing the bridge to come loose.
Cleaning the guitar
For cleaning the guitar use a slightly water dampen cloth, or use a guitar cleaner, do not use furniture cleaner or other cleaners not specified to use on guitar cleaning,
For French polish finish do not use any cleaner, only use a slightly water dampen cloth. Always play the guitar wearing long sleeves or use a cloth between your arm and the top. French polish is very sensitive to acidity and your sweat will dissolve and rotten the shellac used in the finish.
Does not use super high tension strings, Cervantes Guitars are designed to be played with Medium tension or high tension strings.
It’s better to change one string at a time instead of taking all the strings at once and then re-string the guitar. Do not cut the strings when they are tensed, first unwind the string until is fairly loose then you can cut it if you like to remove the string faster.