Adjusting the truss rod should only be done by people who know what they are doing, particularly on instruments that are under warranty. If you break your truss rod, the factory will not honor the warranty on the instrument.

People who adjust their own truss rods have been known to cause horrible damage to necks. Do this at your own risk. I cannot overemphasize the danger of doing this yourself. I cannot and will not assume responsibility for any damage you cause to your instrument by doing this yourself.

A critical part of banjo setup is acheiving a good comfortable action. In order to have a proper action on your banjo, you must adjust the neck to the correct tension for your strings.

Most modern banjos have a truss rod in the neck. This rod serves to counteract the pull of the strings. The necks of most modern banjos are quite thin, and in many cases would bend so much from the pull of the strings that they would have very high action and would be difficult for most of us to play.

In Gibson instruments, and many other instruments, this truss rod is accessible through a plastic or mother-of -pearl plate located on the headpiece of the banjo, where the tuning pegs are, just above the nut. On some other instruments, the neck must be removed from the rim of the banjo to access this feature. Usually the neck is adjusted by using a small nutdriver, t-wrench or allen wrench, depending on the instrument you have.

If you have never adjusted a neck before, it would be a good idea to watch someone else do it first, so you can see how it's done, but for the brave and adventurous, here is the basic principle: by adding tension to the truss rod, you decrease its length, which causes the neck to pull backwards against the pull of the strings. By loosening the truss rod, you increase its length, which causes the neck to bend in the direction of the pull of the strings. The direction of the turn depends on the type of truss rod you have. Some tighten when you turn the adjusting wrench clockwise, others loosen when you turn it clockwise.

So you must be very careful when you adjust the neck. If you turn the adjusting wrench more than 1/2 turn, and the defect in the neck is not corrected, return the wrench to its original position, and adjust slightly in the other direction. Adjustments of more than 1/2 turn are quite risky and may break the truss rod. So go slowly. If you don't see any improvement in the neck after you have gone about 1/2 turn, seek professional help--the neck needs more attention than you can give it yourself!

NEVER, EVER, just crank away at the rod, and hope for the best. This is VERY dangerous. The Guitar Player Repair Guide by Dan Erlewine, available from Stewart MacDonald and other music supply houses has a wealth of information on the subject.

If you feel that you must adjust the neck yourself, here are a few things you will need to do. First, put a set of the strings you are going to use on the instrument and play it for a few days, just to let the neck settle into the proper tension. Next, make sure you have the proper wrench for your instrument. A wrench is cheap. A truss rod replacement is very expensive. Also, get a feeler gauge that has a blade about 10 thousandths to 15 thousandths of an inch thick. Select a clean place to work, and place a towel on the table.

Place the banjo on the towel, with the resonator lying solidly on the table. Stand at the end of the table where the headpiece of the banjo is. Lift the headpiece of the banjo and sight down the first string. If the frets below the first string are nice and even, with no sudden lumps or bumps, that's fine. Now look down the fourth string. If its frets are nice and even, you're on a roll! What you are looking for at this point are individual frets that protrude above the rest of the frets. These will cause buzzing and will make the neck difficult to adjust. If there are troublesome frets, take the banjo to a repairman, and confirm the diagnosis. Then have him level the frets for you. He will also adjust the neck, at that time.

If the frets are nice and even, then check to see if the neck is straight. You can do this with a straightedge, or you can fret one of the strings at the first and 22nd frets, and see if it touches all of the frets on the neck evenly.

Now that the neck is straight, you need to introduce some "relief" into the neck. This is a very slight amount of bow. You need a slight gap. Measure it at the 7th or 8th fret--near the center of the neck. It should be somewhere between 10 and 20 thousandths of an inch. The relief serves to prevent and eliminate buzzing.

If the strings are flat against the frets, loosen the truss rod a little at a time, until the proper relief is present. Remember, if you have to go more than 1/2 turn, you have a problem and should take the instrument to a professional.

DISCLAIMER

Adjusting the truss rod should only be done by people who know what they are doing, particularly on instruments that are under warranty. If you break your truss rod, the factory will not honor the warranty on the instrument.

People who adjust their own truss rods have been known to cause horrible damage to necks. Do this at your own risk. I cannot overemphasize the danger of doing this yourself. I cannot and will not assume responsibility for any damage you cause to your instrument by doing this yourself.

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