How to keep your guitar in tune

Don’t panic, it sounds like you’ve got a few simple setup jobs to do keep your guitar in tune.

• Make sure your strings are stretched in
• Check the slots in your top nut
• Lubricate your top nut
• Set the intonation on your guitar

Stretching the strings

Metal stretches quite a lot, so you have to stretch in the strings so they stop going flat when you play and allow you to keep the guitar in tune. You should do this with strings you’ve just changed.

Here’s how to do it.

1. Hold the guitar in the playing position (or on a strap).
2. Attach your tuner and tune the 6^th string to pitch (usually your low E).
3. Hold down the 6^th string at the 1^st fret with your fretting hand (left hand if you’re right-handed).
4. Loop the first three fingers on your other hand under the 6^th string at about the 12^th fret
5. Lift the string up and down twice at 90 degrees to the fret board by about 1.5 -2 inches off the board and gently release so it doesn’t whack down on the frets.
6. Check the tuning of the string. You will probably notice it has dropped down to C# or D.
7. Retune back to pitch and repeat steps 3-6 a few times until the string stays in tune.

The string is now stretched in and you can move on to the 5^th string. Do steps 2 -7 for the 5^th string (usually tuned to A).

Move through the strings from the 6^th down to the 1^st. You will notice the plain unwrapped string stretch in faster with fewer reps of the stretching process. Once you’ve done that, check all the strings are in tune again. They should stay there now.

Check the slots in your top nut

The top nut is the slotted piece of bone, plastic, graphite or metal at the top of the neck, at the end of the fret board before the strings go into your tuning pegs.

This is also sometimes called the ‘nut action’. If the nut action is too high you end up bending the string as you hold it down to play. This makes the string sharp when you are playing down at the first few frets and won’t allow you to keep the guitar in tune.

The truss rod needs to be adjusted before you make any changes to the nut action. If you want to check this quickly before you begin it will save a lot of hassle and repairs to the nut later. Here’s how I approach it.

1. When you’ve got the guitar in tune, put a capo across the first fret.
2. Hold down the 6^th string at the last fret (21^st, 22^nd or 24^th depending on your guitar).
3. There should be a small gap under the string at the 8^th fret between the fret and the bottom of the string. When I say small it should be about the thickness of a business card.
4. If it’s much thicker than a business card, the truss rod needs to be tightened with the correct Allen key, spanner or screwdriver.
5. If there is no gap then the truss rod needs to be loosened a bit (1/4 turn/ retune/ re-check).

This is called setting the relief because it gives a slight concave shape to the neck and allows the strings to vibrate in the middle of their length without rattling the frets.

Now you’re ready to check and adjust the nut action.

To do this you need an Engineer’s Ruler or a set of feeler gauges. The rulers are usually metal and the measurements start from the end of the ruler; unlike a student ruler that has a small space before the measurements begin.

1. Hold the guitar in the playing position.
2. Measure from the top of the 1^st fret to the bottom of the 6^th string. The gap should be about 0.75-1.25mm (high end of this for heavy string gauges or acoustics).
3. If the nut action is significantly more than 1.25mm, the slot needs to be deeper because it will be going sharp as you play it at the first few frets. To do this you need a set of nut slotting files. These come in different gauges for each string so the string fits the slot and doesn’t catch in it.
4. Lay the guitar down securely so it won’t drop or rock. Slacken off the string and take it out of the slot. File a little with the correct gauge of file, don’t go mad. Blow out the slot to get rid of the powder the file has produced. Put the string back in the slot. Retune to pitch and recheck the nut action.
5. When you have reached between .75mm and 1.25mm (I would always err on the high side) then do steps 1-4 for the 5^th and 4^th string with the same measurements.
6. For the 3^rd, 2^nd and 1^st string, the measurement for the nut action is lower. That measurement needs to be 0.5mm- 0.75mm

If the slots are too deep you might have a whole different problem so do take care. Having said that, the nut can be repaired or replaced and slotted correctly.

Lubricating the top nut slots

If a string goes sharp (and stays sharp) every time you bend it or use the whammy bar that’s because the nut slots are grabbing the string and holding it sharp.

Try bending the string behind the nut by pressing down on the string between the nut and the tuning peg. This pulls the string back through and the string should be back at pitch. Unfortunately, that won’t keep the guitar in tune and you don’t want to do that every time so you need to lube the nut.

I’m a big fan of wet lubrication for nuts – don’t laugh!

You can buy Nut Sauce, GraphitALL (my favourite) or others. Even lip salve will work at a pinch.

If you don’t want to spend any money you can grab an ordinary pencil ‘lead’. A thin lead in a projecting pencil is best.

To do this:

1. Slacken off the string just enough to take it out of the slot in the nut.
2. Use a dab of the product you have chosen in the slot or rub the pencil lead back and forth in the slot.
3. Put the string back in the slot and tune to pitch.
4. Repeat steps 1-3 for all the strings.

Now there should be no friction in the nut slot and it should move back and forth without grabbing. This will help to keep your guitar in tune.

Setting the intonation

If you tune your guitar and play it quite happily from the 1^st fret to about the 10^th fret but after that it sounds out of tune. Then, when you re-check the tuning on open strings, it’s all good, this is an intonation issue.

What is intonation?

On a guitar, intonation effectively means how in tune your guitar is along the length of the fretboard.

You’ll notice on your fretboard that the distance between each fret reduces as you move up the fretboard. This is a mathematical equation applied during the design process that determines how much a string must be shortened to get to the next semitone up, exactly.

The trouble is it’s not really a constant when different string gauges are used; plus, when you push a string down to fret the note, you actually change the length of the string (very slightly).

In practise, what this means is that as you progress up the fretboard you are going more and more out of tune until it’s really noticeable at the 12^th fret when it can sound terrible. You don’t even have a guitar in tune with itself!

Guitar manufacturers do a couple of things to help get rid of the problem. One is the angle of the bridge which you can’t change but the one you can adjust is the intonation. There are ways of fine tuning this to the nth degree but this is how you can get a satisfactory result.

However, before you start, figure out where the bridge saddles can be adjusted (backwards and forwards) on the type of guitar you have.

1. Hook up your tuning device.
2. Sound the harmonic on a string (without pushing it down) directly over the 12^th
3. Check that the tuner says it’s exactly in tune. Let’s say the 6^th string is an E.
4. Press down the string at the 12^th fret just enough to make a good clean note and read the tuner.
5. If the note when the string is pressed down is flat of the harmonic, slacken off the string slightly. Move the bridge saddle for the string forward (towards the headstock) a full turn.
6. Re-tune the string and repeat steps 2-4 above until the harmonic and the note when the string is pressed down are EXACTLY the same note on the tuner.
7. If the note when the string’s pressed is sharp of the harmonic, slacken off the string a little. Move the bridge saddle for the string back, (away from the headstock) a full turn.
8. Retune the string and retest the harmonic versus the string note pressed down at the 12^th

You’ll get used to how much you need to move the saddles. Some saddles (like on a Telecaster) can be shared between two strings. In this case normally the saddles have been compensated to allow for the differences between the string sharing. In theory you should only need to ‘intonate’ one of the strings that shares the saddle and the other should be good. But check both.

You need to set the intonation for each saddle. It’s exactly the same process on a bass, by the way.

When you can keep your guitar in tune, it’s a wonderful thing but if you don’t want to go through this process yourself, it’s part of the guitar setup service I offer at BBZGuitars. For information on BBZ guitar services in High Wycombe and Buckinghamshire click here.

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