When a guitar is new the neck should be adjusted from the factory to be relatively flat, but over time string tension, humidity, and other factors can cause the guitar neck to bow out of adjustment. Adjusting a guitar neck is done by turning the truss rod that runs down the interior of the neck beneath the fret board. This can reduce excessive forward bow, referred to as relief.
Before adjusting the neck of your guitar it is important to note that many novices mistakenly assume that if the string action is too high, a truss adjustment will fix things. Due to the way strings vibrate when strummed or plucked, some amount of forward relief is normally required in a guitar neck to keep strings from buzzing against frets. If a truss adjustment is unnecessary, adjusting the neck into a backward bow to lower action will make the guitar sound worse, not better.
Though a standard formula would be nice, the ideal amount of relief in a guitar neck varies from instrument to instrument and depends on many factors including string gauge and style of playing. Check the relief before making any adjustments. If it appears to be good, yet the action is high or the guitar buzzes, it might need a nut, saddle or fret adjustment instead. If the neck shows excessive bow, continue with the truss rod adjustment.
One of my recent columns dealt with some of the things that can go wrong with your guitar’s top nut. Big slots, thin strings; the perfect recipe for horrible buzzes and rattles.
Fixing Your Guitars Truss Rod and String Action: Having problems with fret buzz on your guitar? Is the string action killing your fingers? Does the neck of your guitar resemble something like a bow? These problems can be fixed. except the last one. In that case you may need a new gui. Relief describes the bow of the neck. A guitar neck is typically not perfectly straight, but has a dip about mid-way- this is relief. I measure it by putting a capo on the 1 st fret, holding down the string on the fret where the neck meets the body- thus creating a straightedge with the string- and measuring the gap between the bottom of the.
I realize you’re eager to dig out some tools and learn how to repair your faulty nut. Me too. We’re almost there, but, just for a moment, let’s take it down a notch. Think baby steps.
Those nasty string buzzes and rattles can also be caused by nut slots that are cut too low. In extreme cases, the string(s) might actually be sitting on the first fret; or often a string just has to be close enough to the fret to make contact when it’s struck open.
Your gut reaction might be to grab a hammer to beat the offending top nut to death and glue a new one in there. But wait. Just like a nut with worn or over-wide slots, you can repair perilously low slots with super glue.
Again, as Dick Van Dyke would say, diagnosis is everything. Don’t approach your guitar with any tool until you know A) what the problem is, and B) what you need to do to fix it.
Last time I mentioned that you should always make sure that a guitar is tuned up to pitch—or to any alternate tuning that it may be set up to handle. If the tuning isn’t right, it can affect the neck.
If the slots on the nut appear too low—you’re getting the buzzes and rattles when you play open strings, etc.—it could be that the neck needs to be adjusted. If the guitar is tuned too low, the neck won’t have enough tension on it and could be over-bent.
In layman’s terms, this means the middle of the fingerboard is higher than the headstock and body end. This can cause the strings to buzz over the first five or so frets.
To check if your guitar’s neck needs to be adjusted, you have to eyeball the neck itself. Hold the guitar by the body (See PHOTO 1 in the gallery below), never the headstock. If you hold the guitar by the headstock (See PHOTO 2), you’ll put pressure on the neck, which, although slight, will give you a false reading of the neck’s 'straightness.'
Now look down the bass side of the fingerboard (See PHOTO 3). Try closing one eye. You’ll look like Popeye, but it will help you focus. You should be able to tell if the neck is straight, dipped or over-bent. Repeat the process with the treble side of the fingerboard.
Armed with this information, you can decide whether the neck needs to be adjusted. Speaking of which ...
Soon, I’ll show you how to finish adjusting the neck and begin the process of repairing the slots in a faulty top nut. For the latter job, you’ll need super glue, which doesn’t cost much, and nut files. You can buy a set of nut files of varying gauges (about $140) from the likes of Stewart-MacDonald; or buy a single file (about $25) if you’re tackling a particular slot.
I would recommend investing in a full set. That way you’ll be able to build a top nut from scratch one day ... one of the most satisfying guitar maintenance jobs there is.
That’s something I’ll talk you through very soon. See you next time.
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