A banjo neck is an intricate piece of wood that requires extreme precision for its design and production. All mating surfaces between the heel (which connects with the pot) and neck must be perfectly aligned for maximum tone production and playability.
There is plenty of online information and advice regarding setting up a banjo, with different opinions being voiced widely. This article serves to provide some guidelines.
Adjusting the Action
The banjo’s neck is usually constructed of wood such as maple or ebony, depending on its model and scale. It connects to its fingerboard via a metal truss rod which allows the neck to bend or straighten as strings press against frets, using its domed shape with slight slope at bottom to guide strings over frets with minimum effort required for playing the instrument. A good nut will have slightly domed surfaces with slight slope at bottom and should often feature ivory or plastic crownings to help hold strings in place without them slipping off during playback sessions.
A truss rod, commonly found on other stringed instruments, is an adjustable metal rod located inside the neck that can be adjusted to change string angles at either the nut or other parts of the fingerboard. Furthermore, this metal rod can also be used to adjust string height over frets (known as “action”): when higher actions exist it makes pressing down strings easier with your fingertips and producing the notes you desire more quickly.
An effective banjo setup should include adjustments to both the truss rod and nut and bridge to ensure it remains in top condition and enjoyable to play. Adjustments may be performed by either professional tuners, or you yourself (if you possess enough feel). If in doubt of your ability to perform safely or correctly yourself, consult a professional or have one of your students assist with it instead.
Before beginning the truss rod adjustment, make sure that all strings are loose and that coordinator rod nuts have not been tightened too tightly – as doing so could damage either the coordinator rod or neck joint. After loosening one coordinator rod nut and tightening another within reasonable limits (on Goodtime banjos there is only one), loosen the upper coordinator rod nut before tightening very slowly up to 1/6 of a turn; this should put some bow in your neck and improve action of your banjo.
Adjusting the Truss Rod
Humidity can cause the neck of a banjo to lose its straightness over time, or “flatten out.” Additionally, this may result in slight bowing at the base (back) of its neck; however, these effects can be counteracted with adjustments made to its truss rod.
The truss rod of a banjo is an adjustable metal rod running through its pot at its back and can be loosen or tightened to adjust string height, or distance from fretboard to bottom strings. You can make these adjustments by loosening its nut at peghead and turning clockwise or counterclockwise for tightening/loosening respectively.
Tightening the truss rod will raise the action and allow you to play at a higher string height, making fretting easier and creating smoother tones. It should not be difficult for most banjo players; for those without experience doing this themselves we recommend consulting a banjo repairman instead.
New banjos will often need their truss rod tightened more frequently than older instruments, especially after extensive strumming and playing sessions. String pressure pulls the neck out of its straight position and causes it to bow back slightly; when this occurs it must be remembered that truss rod tightening is only a temporary solution; once your instrument has returned to its straight condition retightening will need to be repeated.
If your banjo features coordinator rods, use a nail or Allen wrench to loosen both of its nuts. Rotate each coordinator rod individually until it becomes free from its attachment to the neck hanger bolt neck attachment and loosen. Be cautious not to twist too far when twisting, which could break it; adjust by only 1/8″. For dowel sticks that do not allow adjustment you can try filing its angle by inserting thin shims between its neck and pot.
Adjusting the Bridge
A banjo neck is a long piece of wood which holds the strings, tuners, frets and fingerboard. Additionally, it supports their division into musical notes and chords by means of frets arranged on it. A banjo also contains its two other main components – the nut and peghead. To play it effectively you need to move your left hand up and down fretboard using your left hand in order to produce individual notes or chords; to do this you move toward or away from its pot; while “down the neck” refers back towards its core components nut and peghead respectively.
The neck is typically made of maple, mahogany or walnut and features a channel running along its length to house frets. An adjustable metal rod known as the truss rod runs beneath most of the fingerboard to allow you to customize how much curve is in the neck to prevent strings from buzzing when pressing them against frets.
Another adjustment for string height is the bridge. A lower bridge results in increased action while an higher bridge lowers it. To make these adjustments, loosen all your strings on your banjo and take it to an experienced luthier or read this Deering article on how to set up stringed instruments, or follow these Deering instructions on adjusting bridge feet feet.
Before making any adjustments to your banjo, ensure it is properly tuned. Beginners should follow a “less is more” strategy by gradually making small changes at a time and retuning after every change is made.
If you don’t have access to a luthier nearby, small adjustments may still be made yourself by sanding down the bridge feet and carefully re-gluing them in place. Be careful not to go too far sanding down as that could leave your bridge too low in action.
Adjust the action of a banjo by shifting its bridge either up or down by inserting strips of shim material between its neck and pot, altering neck angle with these changes and taking into account any possible effect they might have. It should only be performed by someone experienced at changing pot angles.
Adjusting the Neck
Wood banjos can vary in their levels of humidity-induced expansion and contraction, which may alter their angles of neck. Adjustments must be made as needed in order to prevent strings from buzzing against frets and make fretting easier without strain.
Adjustments made to either your nut or bridge will have an impact on neck angle, so be careful in your efforts and don’t overdo your adjustments as these could warp the neck!
Banjos feature an adjustable coordinator rod (or “rim rod”) in their pot that allows users to raise or lower the action of the neck by tightening or loosening its extension nut (on Deering banjos, this is located under tuning pegs). You can also turn its knob to change its position.
Once the coordinator rod has been adjusted, you should retighten its extension nut and restring your banjo. It may be wise to replace old strings with fresh ones to ensure proper intonation – this way rust or other contaminants do not hinder intonation!
Shimming can also help change the action of the neck. Although less permanent than using the truss rod, this method requires expert assistance for successful execution. Shimming may be better suited to older banjos with extremely low action settings or those seeking an ultra-low action setting.
Filing the heel of the banjo can also be used to re-adjust its neck, although this practice should only be undertaken with expert luthier advice. If you do choose this path, ensure that both sides of your neck are filed at an equal height in order to ensure an even neck profile all around.