Introduction
Collings guitars and mandolins are among the most finely crafted stringed instruments available today. We use only premium solid tonewoods, carefully and patiently seasoned. We then build and finish our guitars to exacting tolerances. The result of this fine craftsmanship is a tone, look, and feel that is unmistakably Collings — rich, bright, and beautiful. Our guitars are also built to be played, and with just a reasonable amount of care and periodic maintenance, they’ll deliver a lifetime of playing enjoyment. Understanding what affects your guitar’s well-being, both positively and negatively, will help you to apply the proper care and feeding.
Humidity and Temperature
Fine guitars are made of thin pieces of wood that are glued together, and they are directly affected by humidity and temperature.
Humidity is the amount of water vapor or moisture in the air; temperature affects the amount of moisture that air can hold. Both of these factors affect wood because it is naturally “hygroscopic”, meaning it absorbs and expels water. Therein lies the challenge.
A guitar that absorbs too much moisture, through high humidity, expands and swells. This distorts the geometry of the guitar and, consequently, its tone and playability. Add high temperature and humidity can weaken glue joints, even causing them to fail. With prolonged exposure, the glue under the bridge will weaken, allowing the bridge to pull off. Telltale signs of a “wet” guitar are:
- High action
- Swollen top
- Fret buzzing in the high registers (as the fretboard extension rises with the top)
- Distorted back and sides
- “Tubby,” muffled tone, low volume
- Finish cracks (checks)
- Binding separation
Overly dry conditions, or lack of sufficient humidity, can be equally detrimental to your guitar, causing the wood to shrink and crack. It can also result in poor tone and improper intonation. In dry regions, such as mountainous areas, deserts, or northern climates where heated air is common in winter, simple guitar humidifiers may not be sufficient; room or household humidifiers may be necessary to maintain a proper environment. Telltale signs of a “dry” guitar are:
- Lowered action
- Fret buzzing and lifting
- Fret ends sticking out from the fingerboard
- Dips in the top or back
- Finish and/or wood cracks
Gradual changes in humidity and temperature will generally not harm a well-made guitar if they are not exposed to extreme high or low humidity levels for extended periods of time. At Collings, we build and acclimate our guitars in an environment of 49% relative humidity and a temperature of 75 degrees. Storing your instrument in a relative humidity range of 40% to 55% is ideal.
The biggest danger caused by humidity and temperature is rapid or extreme changes, and this is because different materials of the guitar 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 the finish and glue joints in different portions of the guitar as it tries to “cope” with the drying situation. The same is true, in reverse, with high humidity.
Extreme temperatures can wreak havoc, too, as heat weakens glue and cold “chills” lacquer causing finishes to crack or craze.
While you can’t control the weather, you can control your guitar’s environment to a great extent. Here are some simple pointers.
- Keep your guitar in its case when you’re not playing it, as it’s a lot easier to control humidity in a smaller, relatively “sealed” enclosure.
- 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 generally dry winter months or areas. Air conditioning controls humidity in generally hot, muggy summer months or regions.
- Avoid storing your guitar near sources of hot, dry air (such as forced hot air heating ducts), or cold, damp areas (garages, basements, closets with outside walls).
- Never transport your guitar in a car trunk. Temperatures inside car trunks can be extreme in any kind of weather, and 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 environment after being transported in a cold vehicle.
- When traveling cross country, keep in mind changes in local humidity, and protect your guitar accordingly.
- Guitar humidifiers that fit inside the soundhole or extend into the body can be very effective but must be used with care to avoid water damage. Check with a qualified guitar repair person before using them.
Finish Care
Collings guitars are finished with multiple coats of high-grade lacquer, hand-sanded between applications to bring out a deep shine. The resultant finish is thin, durable, and acoustically compatible.
The best way to preserve this finish is to keep it clean, wiping off perspiration and fingerprints with a soft, clean, damp (not wet) cloth. While there are many commercial guitar cleaners available, we feel that a rag slightly dampened with plain tap water and thoroughly wrung out will remove most dirt, then buff with dry, clean cloth. Be sure to keep water away from glue joints, as glues used in the construction of guitars can be water soluble.
If you must use commercial products to clean the finish, avoid those with solvents, silicones, or abrasives. Remember: polishing is not cleaning, as polishes remove finish, along with dirt.
Fingerboards and bridges can occasionally dry out, but they require only a small amount of boiled linseed oil – thoroughly buffed – to restore. Less is always best, and avoid getting oil on the guitar’s finish.
FOAM/RUBBER/VINYL WARNING: We would like to advise our players that many types of instrument stands and straps that employ petroleum-based foam, rubber, or vinyl can cause damage over time when in contact with nitrocellulose lacquer finishes. Many stand manufacturers have developed options that are “lacquer safe”; however, due to variations in finish constitution between makers, it is always safest to treat stands as temporary storage for your instrument. The safest way to avoid finish damage when using a stand is to cover the foam/rubber parts with a soft cotton cloth (guitar polish cloths work well). The safest long term storage for your instrument is in its case, and we recommend always removing your strap after each use, as no part of your strap should be in contact with your instrument when stored in your case.
Action and Playability
Our acoustic guitars are adjusted at our shop with a medium string height and typically about .006″ relief in the neck. The string height can be lowered or raised to suit individual playing preferences by sanding the bottom of the saddle or installing a new taller saddle. Please take care in saddle adjustments, as a minute adjustment at the bridge can greatly affect string height over the fingerboard. Also, too tall of a saddle can result in bridge cracks, so low action should be properly diagnosed before installing a taller saddle, as this may be humidity related.
IMPORTANT: Your Collings instrument’s action/string height should NOT be adjusted using the truss rod! The truss rod’s purpose is to set the neck’s relief, not to raise or lower action. If your instrument’s action has changed, it is likely humidity related (the guitar is getting “dry” or “wet” due to a change in relative humidity, which causes the top to swell or sink). Properly acclimating your guitar in the correct humidity should address the issue, but you should not adjust the truss rod in an attempt to change the string height, as this can eventually lead to permanent damage of the neck.
If your instrument begins “buzzing” or becomes hard to play, it should be inspected by a qualified repair tech, as there are several reasons this could happen, all of which need to be properly addressed.