Truss Rod Adjustment: How to adjust your truss rod for mandolin, dobro, guitar and banjo.

The following is from Mickey Cochran's care and maintenance instructions:

If the neck of your instrument is adjustable, it will have an adjustable truss rod. This is either located on the peghead (under a small plastic, triangular shaped plastic) or in the soundhole where the neck meets the body. This truss rod serves two purposes: 1. to reinforce the neck and 2. to allow future adjustments in case the neck bows backwards or forwards. Most steel string instruments are susuceptible to greater stress due to the tension of steel strings. Usually, you can tell your neck is out of alignment when you encounter buzzing or the instrument has become more difficult to fret. A great tool to have at your disposal when adjusting your truss rod would be a steel ruler which can be pressed against the frets to determine if there's any distance from the frets at a suspected bowing.

Before we get into the steps and procedures for adjusting your truss rod, be aware, if you're not particularly careful, you can damage an instrument even further...

NOTE: Folk of the Wood takes no responsibility for the damage of any instrument by anyone attempting to follow these directions. FOTW highly recommends that you first consult a local repair technician/luthier before attempting this procedure.

1. First loosen any strings above the truss rod cover. Then, remove the screws that hold the truss rod cover to the peghead. Be careful to place all parts in a container to prevent loss. (If truss rod is located in sound hole, loosen most all strings to assure freedom of movement and access to the truss rod.)

2. Once the nut is exposed, and is accessible by your wrench, size the truss rod nut to ensure that you do have the proper wrench (usually 1/4"). Never settle for a close fit; make sure the wrench fits tightly to prevent stripping of the truss rod nut. Otherwise, it will be forever impossible to adjust.

3. Use your straight rule, or sight at the edge of the neck to determine where the bow originates. Be sure to check both the treble and bass sides of the neck. If your neck is bowed in a roller coaster fashion, a truss rod adjustment will not remedy the problem. In this case, only a luthier can plane it properly for even play. If the neck is bowed in a concave fashion, then the truss rod should easily remedy it and straighten out the curvature for ease of play. A neck can either be back-bowed for front-bowed...the back-bowed neck will usually cause buzzing when the instrument is played; the front-bowed will usually make the instrument difficult to fret. Both types of bowed necks can be remedied by proper truss rod adjustment.

4. If neck is front-bowed tighten adjustable nut clockwise.

5. If neck has a hump (back-bowed) loosen the adjustable nut.

Remember, to determine if you've corrected the problem, you'll need to tighten all strings to concert pitch.

The following is an excerpt from literature provided by Saga Musical Instruments:

6. Place guitar wrench on adjustment nut and turn very gently (small fraction of a turn at a time). Keep checking the neck as you proceed with each turn. Once the neck is straight give the adjustment nut a very slight added turn to compensate for the tension the 3rd and 4th strings will add once they are replaced and tuned.

Special note: when making this adjustment it is best to place a straight edge on the frets to assure perfect adjustment. Be careful not to tighten the nut too much because it could result in stripping the threads or perhaps even breaking the truss rod.

The following is an excerpt from literature provided by Breedlove Guitars:

TRUSS ROD

The truss rod in your guitar allows you to counteract the effects of string tension on the neck of your guitar. String tension pulls the neck forward and tightening the rod pulls the neck backward. A properly adjusted truss rod equalizes the tension on the neck. With the adjustments to the rod you can control the amount of bow in the plane of the fingerboard to fit your playing needs. Please feel free to experiment with the rod, by doing so you will learn to compensate for seasonal changes and adjust for different string gauges.

Generally, a properly adjusted truss rod results in a neck with slight forward relief. To check for proper neck relief, push down on the low "E" string at the first fret and the fourteenth fret at the same time. The resulting space between the bottom of the string and the top of the sixth fret should be about .01 of an inch or about the thickness of a business card. By using this as a standard you can adjust to your own playing style.

To adjust your truss rod you will need a small Phillips screwdriver to take the truss rod cover plate off and a 1/4" nut driver for the brass nut on the end of the truss rod.

Tightening the truss rod, turning the nut clockwise, causes the neck to bow backward lowering the string height; too far and the strings will buzz.

Loosening the truss rod, turning the nut counterclockwise, causes the neck to bow forward raising the string height; too far and the guitar is hard to play.

Remember when you are making adjustments to have your strings tuned to concert pitch

Disclaimer: Folk of the Wood, or any of its staff, takes no responsibility for damages that concur from any suggestions or recommendations submitted by e-mail or by phone. It's the responsibility of the owner of an instrument to take precaution in every respect when trying something new or following someone else's recommendations. Always be extra careful about choosing the right products and cleaners for maintaining the integrity of your instrument. If you are in question about a particular product, be sure to consult the manufacturer of the product for any potential problems in application.