Very few things can be as frustrating for a guitarist as a guitar that will not stay in tune. The constant battle can cause absolute hate for an instrument and render it virtually unusable. Luckily, it is usually fairly easy to combat this issue and get everything in tip-top shape! Below are common causes and solutions for tuning instability.
The nut is improperly cut.
This is for sure the most common cause of tuning issues by far. This is usually caused by binding of the string in the nut slot. Easy to diagnose, it is also typically easily remedied. Here is a very easy way to tell if you are having this issue:
- Tune your guitar (if you hear pinging, you can skip the rest for now, because that is binding causing the pinging)
- Bend each string a good amount and check your tuning.
- If a string is flat on the tuner, push on the string behind the nut and check the tuning again. If it seem good now, you have binding going on.
- An alternative version of this would be to use your vibrato to dive bomb. If any strings go sharp, you have binding.
In order to solve binding, you need to properly size the nut slots and lubricate. Resizing may be something you want a tech to do for you as you can mess up by filing too much. If you do decide to do it yourself, it will take a set of nut files and a slow (SLOW) hand. You can always take away, but adding back is not as easy. Afterwards, you can use something like Big Bends Nut Sauce or an equivalent (we use D'Addario's Nut Lube here at Righteous). Once you are done, repeat the original steps and see if the issue is gone.
Your vibrato's knife edge is damaged.
This happens when a vibrato is adjusted for height with string tension on it. It won't always be an issue, but it does happen. This is especially true for some imported models with softer metals, but all guitars are potential victims. When this happens you are best off to just replace the baseplate of the unit and the posts. You can feel this when you move the vibrato. It is just not smooth and is not returning to its starting point.
Bad or old strings can cause tuning issues.
Keep relatively fresh strings on your guitar. They will sound better, intonate better, and stay in tune better once they are stretched. A strings can cause all kinds of issues if it is just bad, even if it is brand new. We use D'Addario strings on our guitars here at Righteous Guitars because they are consistent.
Improperly strung guitars can have trouble with tuning.
If you do not know how to properly string your guitar, you should learn. A properly strung guitar will have each winding on the tuning machine under the last in order to lock in the string. The tuning machines themselves are rarely an issue, but not stringing a guitar correctly can definitely cause problems.
Temperature and humidity changes wreak havoc on your guitar.
A guitar is a sensitive instrument and reacts to humidity and temperature changes. You should always regulate and monitor your guitar's humidity levels and ensure it is somewhere between 40%-55% relative humidity and a temperature that you would feel comfortable being in for an extended amount of time. There are many issues that can arise from ignoring this one little thing.
In conclusion, there are a lot of reasons your guitar may not be staying in tune. There are more too! That being said, it is almost always a nut binding issue. Start there and you will be on the way to getting your guitar to perform to its potential.