How to Maintain a Good Environment for a Guitar
To keep the guitar playing and sounding as the builder intended, you must maintain an environment within a specific climate range. Guitars are always made under these specific temperature and humidity conditions.
Generally speaking, if a human is comfortable, a guitar is comfortable. Keep the guitar in an environment near standard room temperature and the relative humidity at about 50 percent, and you’re never going to hear your guitar complain (even if you have a talking guitar). Don’t go too far with this rule about guitars and humans being comfortable under the same conditions, however. You shouldn’t put your guitar in a hot tub even if you offer it a margarita, no matter how comfortable that makes you.
A guitar can exist comfortably in a range of temperatures between about 65 and 80 degrees Fahrenheit. For a guitar, heat is worse than cold, so keep the guitar out of the sun and avoid leaving a guitar in a hot car trunk all day.
If your guitar’s been cold for several hours, give the guitar time to warm up gradually after you bring it indoors. A good practice is to leave the guitar in its case until the case warms up to room temperature. Exposing the guitar to radical temperature shifts can cause finish checking, the cracking of your finish that results because it can’t expand and contract well enough with the wood beneath it.
Guitars, whether they’re made in Hawaii or Arizona, are all built under humidity-controlled conditions, which stay at about 50 percent. To maintain your guitar, you must also maintain that humidity between 45 to 55 percent. Guitars that get too dry crack; guitars that absorb too much moisture swell and buckle.
You can use a humidifier or dehumidifier to keep your space at the right humidity level. If you can afford a humidifier or dehumidifier, you can achieve good results with the following inexpensive solutions:
Guitar humidifier: This item is simply a rubber-enclosed sponge that you saturate with water, squeeze the excess out of, and then clip onto the inside of the sound hole or keep inside the case to raise the humidity level.
Desiccant: A desiccant is a powder or crystal substance that usually comes in small packets and draws humidity out of the air, lowering the local relative humidity level. Silicagel is a common brand, and packets often come in the cases of new guitars.
Hygrometer: You can buy this inexpensive device at any hardware store; it tells you the relative humidity of a room with a good degree of accuracy (close enough to maintain a healthy guitar anyway). Get the portable kind (as opposed to the wall-hanging variety) so that you can keep it with your guitar.