Care and Feeding
Gradual changes in humidity and temperature will generally not harm a well-made instrument. At The Mandolin Store we keep our shop at 49% relative humidity and a temperature of 75 degrees. So if you keep your instrument pretty close to these ranges, you should have no problems. The biggest danger caused by humidity and temperature changed is rapid or extreme changes. That’s because different parts of the instrument shrink and expand at different rates. For example, if your local humidity drops very rapidly, the instrument cannot acclimate itself uniformly, causing cracks or failure of glue joints in different areas as it tries to "cope" with the drying situation. The same is true, in reverse, with high humidity. Extreme temperatures also can cause problems. Cold cools the lacquer can may cause finish cracking while heat weakens glue
Symptoms of Improper Humidity
An instrument that absorbs too much moisture, through high humidity, expands and swells. This distorts the geometry of the instrument and, consequently, its tone and playability. Add high temperature, and humidity can weaken glue joints and even cause them to fail. With prolonged exposure, the glue under the bridge will weaken, allowing the bridge to pull off. Telltale signs of a "wet" instrument:
• High action
• Swollen top
• Fret buzzing in the high registers
• Distorted back and sides
• "Tubby," muffled tone, low volume
• Finish cracks
• Bindings separated
Overly dry conditions, or lack of sufficient humidity, can be equally detrimental to your instrument, causing the wood to shrink and crack. It can also cause poor tone and improper intonation. In dry regions (mountainous or desert areas) or northern climates, where heated air is common in winter, simple instrument humidifiers may not be sufficient. Room or household humidifiers may be necessary to maintain a proper environment. Telltale signs of a "dry" instrument:
• Lowered action
• Fret buzzing and lifting
• Fret ends sticking out from the fingerboard
• Dips in the top or back
• Finish and/or wood cracks
What to Do to Prevent Problems
• Keep your instrument in its case when you’re not playing it. Most cases are virtually air tight – it’s easier to control humidity in a smaller volume of air.
• Purchase a home hygrometer/thermometer to keep tabs on the relative humidity and temperature. Adjust your home environment as necessary. Plants and humidifiers add moisture in dry winter months. Air conditioning controls humidity in the hot, muggy summer months.
• Avoid storing your instrument near sources of hot, dry air (such as forced hot air heating ducts), or cold, damp areas (garages, basements, closets with outside walls).
• Never, ever, transport your instrument in a car trunk. Temperatures inside car trunks are extreme in any kind of weather. It’s the quickest way to destroy a guitar. Even in the passenger compartment your guitar can be subjected to extreme temperatures. For example, please allow your instrument to warm up slowly before opening your case in a warm room after being transported in a cold vehicle. Abrupt changes in temperature can cause finish crazing.
• When traveling cross country, keep in mind changes in local humidity – and protect your instrument accordingly.
• We recommend Oasis humidifiers that fit inside the sound hole or case