Major Repairs Explained
We often are presented with many instruments in need of repair, some requiring extensive work that only a skilled repairman should handle. Maybe you have been presented with the following phrases: neck reset, bridge reglue, fret crowning/replacement, or bracing reglue. In this article we will explain what these repairs entail and the problems associated with repairs. As a word of caution, this article could lead to “medical-student paranoia”, in which you believe your instrument may need these repairs. We highly stress that only skilled repairmen can identify these problems and perform the repairs needed.
Using paper to gauge the depth of a bridge pulling away from the top.
Bridge reglues are common for instruments that have been improperly stored, or for lower priced instruments in which the bridge was improperly attached to the body. The bridge will initially pull away at the rear (away from the strings) as the string tension essentially pulls the bridge off the body. If left unrepaired, the bridge could completely pull off of the body, taking large sections of the top with it. If a small gap is visible between the bridge and body, try slipping a thin piece of paper between the joint to determine how far the bridge has pulled away from the top.
This repair requires a luthier to heat up the remaining glue on the bridge (without damaging the bridge, top, or finish), clean up the gluing area, and then reglue the bridge to the clean area on the top. Placement and adequate gluing is essential, and a skilled hand can perform this repair with no effect to the appearance. Many times on lower priced instruments with heavy gloss finishes, some finish may need to be removed to allow the glue to make a strong bond between the bridge and top. If the bridge has pulled away some of the top wood as well, care must be taken to match the splintered wood with the respective divot on the top.
Low frets in need of replacement, too low to recrown
After multiple years of playing, the nickel frets on instruments tend to wear down, creating divots along the width of the fret. These divots can lead to poor intonation, uneven playing feel, and buzzing. If you notice deep divots under regularly played notes, or are noticing fretboard wear in these same areas, a leveling/recrowning or refret may be needed.
A fret recrowning and leveling requires a luthier to file the frets down from the top so an even plane is achieved across the tops of the frets. Specialized files are then required to reshape the fret to allow a clean break for the string to ride over. If the frets are already quite low, or the divots too deep, some frets will need to be replaced, leveled and crowned. This requires the repairman to carefully pull the existing fret out without damaging the fingerboard, and to install the new fret securely and neatly (protruding fret ends are not acceptable). Instruments with fretboard bindings require extra care as removing or reinstalling the frets improperly will damage the binding. A good refret/leveling/crowning will ensure pure sounding notes with easy playability across the whole fretboard.
Bracing problems arise when the top has separated from the structural braces that are spread across the inside of the instrument. If a guitar has been excessively dried out or humidified, the glue joint holding the braces to the top can fail. The top will then proceed to belly or warp depending on the bracing failure, and can lead to greater damage. Loose braces can be diagnosed by excessive bellying of the top, or rattling noises emanating from the body.
Access to the inside of the guitar can be quite limited and frustrating to work with, so as with all of the repairs in this article, it is best left to a skilled luthier. Hide glue is used to rejoin and repair any loose or cracked braces, and the top returned to its regular position.
Detail of a dovetail joint at the body
This is one of the most difficult repairs performed on an instrument. As the instrument ages, the wood begins to settle and adjust according to the strength of the wood and construction methods. For many instruments (vintage pieces in particular) the tension of the strings will pull the neck in and into the top, causing an increase in angle between the level of the neck and top. The action will increase until it becomes impossible to lower the saddle any further. In addition the intonation will be compromised as the scale length shortens slightly. If the action of the guitar becomes unplayable in the upper range and little saddle is left above the bridge, a neck reset may be required. On a guitar with a proper neck angle, the plane of the fretboard will line up evenly with the top of the bridge. Too steep of an angle leads to high action, too shallow leads to buzzing and a high saddle.
Detail of a dovetail joint at the neck
This complicated procedure involves removing the neck which usually requires heating up the glued fretboard extension and the neck heal as well (for dovetail joints). A repairman must also take care not to damage any of the body surrounding the joint when removing the neck. When the neck is replaced, some compensation must be taken into account for when string tension is placed back upon the instrument, as a poorly reset neck may settle back into its original, unplayable position. Over compensating will lead to an excessively high saddle, and buzzing in many positions on the neck.
One point should be made regarding neck joints: many companies are introducing “bolt-on” neck joints as a solution to neck resets. Even if the whole joint is bolted on, only a skilled luthier should attempt a neck reset. Bolt-on necks still require knowledge of proper neck angle and setup, and a skilled luthier should have no problem with removing a glued neck joint cleanly.
These repairs are quite complicated and require many years of repair experience to complete cleanly and effectively. We do not recommend a layperson attempting any of these repairs on their treasured instruments as even more serious damage can result from poor repair work. All of the repairs listed above apply primarily to guitars and other stringed instruments. Other instruments such as autoharps, violins, and band instruments may need equally difficult repairs not covered here. In many ways, instrument repair is similar to auto repair: there are repairs involving parts that you never knew existed. Likewise, you should only take a repair to shops that perform in-house work as the repairman should be able to directly explain to you the problems, symptoms, and repairs involved with your instrument. Music Folk has seen many instruments that were deemed in need of neck resets or fretwork, but only truly required minor adjustments as well. Many times these repairs can be quite costly and time-intensive, but should only have to be performed once in the lifetime of an instrument treated with proper care. If you have an instrument that you suspect may need extensive repairs, or even a simple setup, email us, or call us directly at (314) 961-2838.