A rough guide to guitar set up and maintenance.
There are many things that are addressed with a guitar set up. The 5 main points being tuning stability, neck relief, action , intonation and pick up heights. There are many adjustments that can be made to optimise the performance of these 5 things and get the best out out of your guitar.
Tuning Stability
The main contributing factors to tuning stability are the breaking points on the guitar i.e the bridge (saddles), the nut and the tuning pegs. So lets start with with the saddles. Badly corroded or worn saddles can cause all sorts of problems with tuning and unwanted noises and buzzes. Sharp edges on the saddles cause friction, so the string can’t return to it’s original position after string bends. This causes a lot of problems particularly when using a floating tremolo bridge. A nice smooth finish on the saddle will also contribute to good tone transfer and sustain.
There are various solutions to these problems. In some cases you may well just be better off with replacing the saddles altogether. Most of the time filing down the rough edges with some micro files and cleaning them up with a mixture of thinning solution and oil works a treat.
Similar issues can be caused by a badly cut, or worn down nut. Again any friction at this point can prevent the string from returning to position when in travel. And can also create unwanted noises. The solution to this is either filing it down or replacing it. If you have problems with the nut this can be a good opportunity to replace it anyway. A lot of guitars come out of the factory fitted with plastic nuts, which never perform as well as say a good quality bone nut.
Now to the tuning pegs. Many guitars come through here with loose tuning pegs and sometimes bent out of shape. When it’s the latter then there’s no other way around it other than replacement. Which usually means you’ve got to replace the whole lot. Unless you get lucky and you find someone on Ebay selling the exact tuner you need. Again if the tuning pegs are damaged beyond repair then maybe this is a good opportunity to replace them with something better anyway. And if tuning is something you have a problem with, locking tuners can be a good solution to this.
If the tuning pegs are a bit loose then the nuts may just need tightening- (See fig 1).
Neck Relief
Neck relief is the relief in the neck from string tension. The truss rod in the neck, which can either be adjusted at the headstock or the heel of the neck, can be altered to create the correct amount of force in balance with the tension of the strings. The best way to measure this is to put a capo on the 1st fret, depress the 6th string at the last fret, and with a feeler gauge measure the gap between the bottom of the string and the top of the 8th fret. This should be set between 0.2mm and 0.3mm. If there’s too much relief (action too high)then the truss rod should be adjusted clockwise (sighting from behind the headstock or from behind the body depending on where the adjustment is), to remove excess relief. If the action is too low then the truss rod should be adjusted anti clock wise to allow the strings to pull more relief into the neck. Small adjustments should be made at a time whilst being careful not to over tighten.
Action
The action comes down, mostly to personal preference, but there are some guidelines that can help as a starting point.
Saddle distances, in relation to each other, should be set to the radius of the neck. The neck radius is the measurement of the curvature of the neck (See fig 3).
You can use an under string radius tool to, firstly, work out the radius of your neck.They usually come as a set with different sizes. Secondly you can use it as a jig to set the radius at the bridge (see fig 4).
Setting the action comes down to personal preference. Players with a lighter touch will be able to get away with a lower action. And those who have a more aggressive playing style may need the action to be a bit higher to avoid fret buzz and rattles.
As a starting point measure at the 17th fret from the bottom of the string to the top of the fret. Set somewhere between 1.5mm and 2mm until you get the action and feel you’re looking for.
Intonation
Intonation is the consistency of pitch between octaves along the fretboard. The way to check this is to hit the harmonic note on the 12th fret and compare the pitch with the fretted note at the 12th fret. Being careful to fret evenly with your finger behind the fret. If it’s sharp then the string needs to be be lengthened (saddle moved back). If it’s flat then the string will need to be shortened (saddle moved forward).
Pick up heights
To set pick up heights, depress string at the last fret and measure from the top of the pole piece to the bottom of the string. A good starting point is 2.5mm Bass side and 2mm treble side. Again this boils down to personal preference, but the main thing to avoid is adjusting the pick ups too close so the magnets pull on the strings. This can cause noise issues and tuning problems. Higher output pick ups will need to be backed off further than lower output pick ups. Pick up heights are kind of like another tone control. The closer the pick up to the string the brighter the sound will be. Also break up will be achieved sooner. The further back the pick up is moved a more open, ‘acoustic’ sound will be achieved with more headroom.
Conclusion
It’s important to make these checks and adjustments in this order. Also every time an adjustment is made check your tuning as the string tension will change. Another good practise is to lubricate all the string breaking points. A dab of vaseline at the string trees, nut and bridge works a treat. This will help with overall tuning stability. Also when fitting a new set of strings make sure to stretch them in before starting with the set up.
