ELECTRIC GUITAR SET UP PROCEDURECopyright 2010 Steve Carmody
The thoughtful design and close-tolerance machining of the mechanical components of
most electric guitars enables them to be set-up and adjusted with great precision.
But it is important to make these adjustments in the correct
order- Neck-Nut-Bridge saddles. Making fine tune adjustment to any of these elements
without reference to the others, or out of this order, will prevent a guitar's
true potential from being realized.
In the following essay I will outline the steps involved in the set up of an
electric guitar. These guidelines will not address the nuances of Floyd Rose
style bridge assemblies. I am presuming here that the frets on the guitar in
question are level and properly seated, but it should be noted that the process
of leveling and dressing/crowning guitar frets is indeed sometimes necessary
before a set-up can be performed. I am also presenting this outline without
an in-depth itemization and discussion of the specialized tools that
are necessary for some of the adjustments.
Step 1
On guitars with tremolo bridges, the bridge must be stabilized before any
adjustments are made. Regardless of the manufacturer, the correct position
for any bridge, under string tension, is going to be parallel to and
essentially flush with the top (or up to 1mm, or so, above the top).
Ultimately, we want the bridge assembly to sit such that we have a range
of adjustability over the bridge saddles, so that we can dictate the
preferred string height over the fretboard.
Some bridges have a lock position and at this point should be engaged.
Other floating bridges will need to be stabilized by using pieces of wood
fitted inside the cavity (accessed from the back of the body) to prevent the
tremolo block from moving. Vintage Fender-style tremolo bridges can be
stabilized by fully tightening the spring tension screws. Whatever method
is used, the bridge must sit as we will want it to when we are done with
the set-up procedure- parallel to and nearly flush with the top- so care
must be taken at this stage to get the position of the bridge right.
Step 2
With the bridge in a locked position, bring the strings to your preferred
tuning and check the neck curvature. If you don't intend to keep the
instrument in standard concert pitch, tune it as you intend to normally
tune it- half a step down, three steps down, whatever. Also, you should
have the gauge of strings you intend to use on the guitar at this point,
if you did not already. Both the string gauge and the tuning of the strings
dictate the amount of tension that is going to be pulling on the neck, and
everything about the adjustments you are about to make is affected by the
tension on the neck.
Step 3
With the correct strings on the guitar, and the strings tensioned to the
tuning you intend to use, place a capo at the first fret, or depress the low
"E" string at the first fret. While doing this, depress the same string at
the 12th fret. Site along the bottom of the string and note its relationship
to the top of the frets up and down the fretboard between the fretted
positions. The string in this situation, since it is under tension, is
essentially a straight edge, and the curve, or profile, of the fretboard
can now be seen. Generally, a gap of 1/64 - 1/32 " between the bottom of
any string and the tops of the 6-7th frets (when fretting the string at
the 1st and 12th frets or higher) is considered acceptable. You could go
a hair flatter, or even a bit more curved depending on the needs of a given
player, but start here.
While continuing to keep the E string depressed at the first fret, move up
the neck from the 12th fret to the end of the fretboard, continuing to
depress the string at each of the successive frets. As you move up the
fretboard, watch if and how much the distance between the bottom of the
string and the top of the frets in the 6-7th fret range changes, if at all.
The less the gap rises, the flatter, overall, the neck is. Using this
method you may discern that there is more curve in one area than another,
and not necessarily centering on the 6-7th fret area. In some cases
this curve will be resolved by changing the tension on the truss rod. In
other cases, adjusting the truss rod tension will not resolve them, and
fret leveling, refretting, or heat bending the neck(rarely) may be
necessary.
After making your observations about the curve in the neck, make your
adjustments of the truss rod, if necessary, until you have the amount of
forward curve you are looking for. In the best case scenario this will
mean that you end up with a slight forward profile, when fretting the 1st
and 12th frets, usually no more than 1/32", focused in the 6th-7th fret area and
tapering towards flat in either direction.
Step 4
Once you are satisfied that the curve of the neck is in the
acceptable range, check the string height at nut. Depress each string at
the third fret and look back towards the nut to see how the string sits over the
first fret. The string should neither be sitting on the first fret nor far
enough above that you can see a gap thicker than a sheet of paper. This is
a very subtle point to reach and you need proper nut files to set it. This
setting is crucial both for achieving proper playing height up the neck,
and for achieving proper intonation. If it is too high here, you are going
to end up setting the action lower at the saddle than it really ought to be,
resulting in buzzing ( the string will measure out "correct" at the 12th fret
yet actually be inclining down as it progresses towards the bridge saddles).
Additionally, a string set too high at the nut will likely play noticeably
sharp at the first and other lower fret positions.
Step 5
With the neck profile and nut slots correct, approximate the
positions of the string saddles for correct intonation. Low E and G string
will set back about 3-4/32nds of an inch longer than the exact scale length.
The A and B strings will set back 2-3/32nds , The D and high E about 1 32nd.
Scale length equals the distance from the fretboard edge of the nut (where
the strings bear off) to the middle of the twelfth fret, times 2. If the
measurement from the front of the nut to the middle of the 12th fret is
12.75", then you have a 25.5 inch scale length (12.75 x 2= 25.5) Final
positioning is done once saddle height is determined, but you need to be
close to this final location when determining the saddle height.
Step 6
Now that the neck and string slots at the nut have been
adjusted, you can set string height at the saddles.
Measure the height of the strings at the twelfth fret. For most playing
styles, the height between the bottom of the low "E" string and the top of
the twelfth fret should be a hair over 2/32". The High "E" string should
be set at 2/32". The other strings should gradually flow between these
measurements. This is where I would start, but the player's style
(particularly their right-hand attack), as well as string gauge, scale length
and individual neck nuances may necessitate deviation from these numbers.
In the ideal scenario, once set, your saddles should neither be flush
down on the bridge assembly of the guitar, nor extended so high they could
go no further. This saddle height relative to the bridge assembly is a
reflection of the neck angle. If the saddles sit flush, the neck angle
is not set back very far and vice-versa. This is where you should decide
if your neck angle is in need of adjustment ( if you have a bolt-on neck).
Check the measurement at the 12th fret then progress up the neck, measuring
every couple of frets. The string height should continue to gradually
rise, if it doesn't the neck is set back too far and has to be tilted
up just a little. This is a very sensitive adjustment and the thickness
of a couple sheets of paper can make a big difference. Some Fenders have
a neck tilt adjustment screw that is accessed with an Allen wrench
through a hole in the neck screw plate. The strings must be loosened,
then the neck screws, then the tilt adjustment screw is tightened or
loosened. Never do this when the neck screws are tight! If you don't
have a tilt adjustment, thin shims of wood veneer are fitted in the
neck pocket to adjust neck angle. Uneven frets are also a possibility.
If , after having followed all the above steps, you are still getting
fret buzz, you must establish that the frets are all even. But this
leads us to fret dressing, which is another story altogether.
It should be noted that some bridge assemblies have pre-set,
non-adjustable saddle pieces. The Gibson "tune-o-matic" bridge is
just one example. On these bridges you will have an overall height
adjustment post on either side of the bridge. For these bridges,
measure the height at the 12th fret for the low and high "E" strings
and make your height adjustment for each side at the respective post.
The other string heights will be defined by the bridge assembly.
Step 7
Once you have the height of the strings over the fretboard
adjusted, you can fine tune the intonation setting with an electronic
tuner. If the saddle locations are already close to where they should
be (based on your measurements), your saddle height should not have to
be changed very much as you make the final intonation adjustment. If this is a tremolo
bridge and it is blocked, tension the tremolo spring claw to the correct
setting( this adjustment will be the subject of a separate article).
Step 8
You should have been making all the above adjustments with
the preferred gauge of strings, but since you have probably loosened and
tightened the strings a number of times over the course of this process,
you should now put on a fresh set and do a final check of all the settings
Neck adjustments in particular can tend to settle in over the a couple
hours after they have been done, so I find it best to then let the guitar
sit overnight and do a final check the next day. The bottom line in ending
up with a quality set-up is making each of the important adjustments in the
correct order: Neck- then Nut- then Bridge saddles.
Steve Carmody is an independant guitar repairman and luthier with a shop in Silver Spring, Md.
He has has been doing guitar repair and restoration full-time since 1990.
Questions about this article or anything else related to guitar repair? Send e-mail to - GuitarRepairShop@aol.com
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