Although most of us wouldn’t relish the idea of replacing the machine heads or bridge/saddle assembly on our acoustic guitars, it’s important to recognize that it can be done. Often tedious and sometimes requiring exceptional patience, it is, nonetheless, a procedure most of us can successfully accomplish. (It’s definitely a labor of love.) In fact, all hardware can be replaced if need be, as well as most necks (including fretboards and even frets) and truss rods, and even loose braces can be re-glued--though it may involve renting or buying a few specialty tools.
But, structural damage to the guitar body itself is another thing. It’s therefore necessary to know when to be concerned.
As any guitarist learns soon enough, cracks are among the most common structural problems afflicting a hollow body guitar. By their very nature and design, all hollow body wood instruments (including violins, cellos, violas, and other wooden box-like instruments) react to their environment in an effort to adjust to changes in heat, cold, humidity, dampness, as well as physical contact. That’s what wood does. And while a split on the top, side, or back is not something that should be ignored, the vast majority can be repaired relatively simply if dealt with early on. In fact, many can be repaired right at home with minimal effort and tools.
As part of the cleaning and polishing process (as detailed in Guitar Fundamentals: Cleaning the Finish of Your Guitar (the Body) and Guitar Fundamentals: Polishing Your Guitar (Pointers and Caveats), a visual and tactile inspection of the body should be performed. The hands-on nature of the cleaning and polishing process naturally provides the guitar owner a prime opportunity to feel cracks as they begin to form. But rather than panic--or just rub in a little extra polish as many guitar owners are prone to do--be prepared to deal with them at first sight. And doing so while the instrument is stripped down for cleaning or restringing is a prime opportunity to keep a minor problem from becoming a major one.
The simplest and most reliably-easy crack to repair is the “hairline.” Those are the ones that typically form at the joints or seams, and sometimes in the grain of the wood itself. But before jumping to the conclusion that a crack is structural, examine it closely in good light--with a magnifying glass is necessary. Often what initially appears to be a crack in the wood is actually a “check” or “craze,” naturally-occurring cracks in the finish--not the wood. As any guitar with a natural finish ages, it will acquire countless checks and crazes, which most guitar lovers view as part of their aging beauty. (That’s what results in its unique patina.) It’s best to learn to distinguish these common signs of maturity from actual damage early on so that you’re more attuned to the structural changes your guitar will inevitably experience.
Unless a guitar has been subjected to a shocking blow--throwing, dropping, crushing--potential structural problems can most often be recognized for what they are while they are still manageable. A number of very simple repair methods involving gluing and “tape clamping,” gluing and metal clamping, and super-gluing can be effectively executed by most people; (methods that will be discussed in a future article).
However, unless you intend to attempt any and all structural repairs in the future--which is certainly within the realm of possibility for many individuals--you'll want to think twice about attempting to repair more serious damage, especially on older or vintage guitars. On the other hand, unless you intend to relinquish all such repairs to professionals, it's good to learn basic repair methodology so that small cracks can be controlled. Guitarists who adopt the idea that an acoustic guitar is a “living” creature that will need love and care--rather than just an inanimate object--are best prepared to help a fine instrument age with grace and dignity.
Forty years experience as a professional guitarist
Guitar Player Repair Guide, D. Erlewine
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