Learn how to make neck adjustments on an acoustic guitar truss rod from a professional guitar technician in this free guitar care video.
Hi, my name is Tim Ambrosius. I'm a professional guitar technician. I'm going to show you how to adjust the neck on your acoustic guitar. First, what you need to do is make sure that your guitar is all up to pitch and in tune. And, then what you're going to do is look down the neck. As you can see, this neck is under bowed a lot. So, what we need to do is tighten the truss rod to compensate for that under bow. Now, if it was over bowed, you would see that the frets would be really, really close to the strings. You could see like a hump in the neck. If that was the case, then we'd have to loosen the truss rod. Okay, on most acoustics you're going to find the truss rod is going to be located right down there, right where, right underneath the neck where it meets the sound hole, right inside there. Now, since this guitar is under bowed, what we're going to need to do is tighten the truss rod. So, we just take our allen wrench. This one is pretty bad, badly under bowed so we'll do about three quarter turns. I can feel it tightening. Then, check the tuning on it. Then, you just want to site down the neck again and compare the neck to the strings. As you can see, the neck is a lot straighter than it was. It's almost straight. You want to leave just the tiniest bit of underbell in it. Compare it to the string itself. You want to see the neck compared to the string. And, it's not as under bowed as it was. And, that way you're going to get a lot lower action. It's going to be a lot better playing guitar.