Guitar Neck Problems

Bowed Necks (Excessive Relief)

The upward bow caused by string tension only becomes a real problem when it is excessive and unadjustable. The truss rod's main job is to keep the strings from pulling the neck into a exaggerated bow shape. A problem occurs when the bowing can not be controlled or adjusted by the truss rod. This happens when either the neck has no adjustable truss rod, the rod is broken or it has merely lost the battle with tension and is helpless to straighten the neck.

When appropriate, some necks can be planed and re-fretted with a fret wire which has wider fret tangs to encourage straightening and stiffening of the neck.

Twisted / Warped

Twisted Neck
Fingerboard has been planed to correct.

Unlike excessive relief (an upward bow of the neck) a twist occurs in such a way as to render the neck lower on one side than it is the other.

Very minor twisting may not create noticeable playing issues but more substantial deformities can cause fret out and buzzing.

Although twisted necks need to be evaluated to determine the best remedy, planeing is sometimes a remedy. Because wood is removed, the severity of the twist, fingerboard and neck thickness must be taken into consideration. It should also be mentioned that a new instrument exhibiting neck twist may continue to do so in the future, making the repair temporary.

Planeing an older neck, which has likely taken a set and stopped twisting is more favorable.

Breaks frequently occur where the peghead meets the neck.

Broken Pegheads

Without a doubt, the most vulnerable area of the neck is the point at which the peghead and neck merge. The angle of the peghead creates what is called "grain run out". This makes the area behind the nut more vulnerable than other areas.

In an attempt to reinforce this area you will find that some manufacturers have used different methods. As seen on many Martin guitars, additional wood is left in place to thicken the area. This is known as a volute.

Others have chosen to make the neck out of more than one piece of wood. The peghead grain can then be closer to quarter and joined to the neck via scarf joint or other method.

Regardless of the methods used to build guitar neck's breaks occur.

Broken Peghead

Loose Necks

A set neck (glued on guitar neck) can come loose where it attaches to the body by impact, heat or failed glue joint. A loose neck can create high action and often leaves a visible gap between the heel of the neck and the sides. You should remove string tension if you discover the neck is loose from the body to prevent severe damage.

Because necks are attached to the body using several methods, the repair will depend on the cause.

This neck heel fractured after coming loose and being left
under tension.

This Ovation's neck was epoxied in place. The glue held
but the actual wood failed (after impact), leaving bits of the heel still glued
to the dovetail joint.

Cost

Because most acoustic guitars are glued in place, the cost to replace an un-repairable neck is usually prohibitive on less expensive instruments.

A neck fitting on an instrument with a glued in dovetail and the cost of the replacement neck can easily run up a bill of $500 to $800 or more depending on the manufacturers pricing of the neck itself.

Bolt on necks which do not require as much labor are often less expensive to replace.

When a factory made neck is unavailable and a used, donor neck can not be found, custom replacement necks can be made by those offering this as a service, I do not.