For most new guitar owners, the first thing you may want to do after you receive a new guitar would be to make some adjustments if you find the settings unsuitable for your needs. For regular players, a great playing guitar that over time develops less fluid output may be a sign that your truss rod would use some adjustments or tunings to keep it in shape.

The thin truss rod runs the length of the neck, counteracting the strings tension to help keep the neck straight. Truss rods have undergone significant changes since the first non-adjustable design was introduced. These days, almost all guitars come fitted with adjustable rods that can be modified with a screwdriver or an Allen wrench.



Commonly, there are two main styles of adjustable guitar truss rods: single action (one-way) and double actions (two-way). While the one-way rods straighten the neck against tension and upbow, the two-way rod on the other hand not only straightens the neck but also forces a back bowed neck into a straight or up bowed configuration.

So, even though they work in different ways, truss rods are designed to counteract the tension on the guitar strings, which are often pulling on the neck.

Usually, you would know your guitar needs some fine-tuning when the neck of the guitar has too little or too much back bow.