Guitar set up

Here is how to set up your guitar.Use a tape measure and measure from where the nut touches the fretboard to the 12th fret, note down this measurement. Now measure this distance from the 12th fret to the where the string crosses the bridge. this measurement should be the same as the first one. if not move the bridge forward or back to where it matches.This is for the 1st E string.Do the same for the large (6th) E string. on the second measure add one quarter of an inch or 4 mm for compensation of the string sizes). This gives you the correct location of the bridge. Now adjust the height of the bridge to allow for an approximate height of one eighth of an inch or two mm from the surface of the fretboard to the bottom of the large E string at the 12th fret, the small E string will need just enough height to prevent buzzing against the frets. Setup is for  guitars with a floating bridge, as used on an archtop guitar . A guitar with a fixed bridge such as an Les paul or similar guitars only need the height(action) adjustment. A classical guitar has a fixed setup and does not need any adjustment. Your setup can become compromised when you change strings if you take all the strings off at once. It is a good idea to change the the two E strings first  so as to let the others hold the bridge in place, then change the others as you wish. This way you are less likely to mess up the set up. Height adjustment ( action)is very important not only to keep the strings from bussing on the frets but to find the optimum sound  of the string vibration and comfortable playability.Too high action gives a clipped sound to the harmonics of the string viberating from side to side.

couldnt have said it better myself.

http://www.mrgearhead.com/ghad/Guitar_Setup.pdf

    I second the MrGearHead site recomendation.  This is what I used to do my first set-up.  Jalma gave some good advice for set-up the low E, but glossed over the need to adjust each adjacent saddle closer by the string size.  Also, this will give you an initial set-up.  You may well still have to make fine adjustments to the string length to set optimal intonation.
    In fact, once the initial set-up is performed, you probably only need to adjust the bridge for intonation, unless maybe if you made a radical string size change.

More concisely, it's a string change, an adjustment of neck relief, action, intonation, and possibly pickup height.  More complex things repairs might be involved if the guitar really needs it.

how about on acoustics?

Pup,

For acoustics, you can still adjust the truss rod to fine tune your string action/height.  Even if you keep them under ideal conditions -- proper humidity and proper temperature, acoustics need this kind of adjustment every so often.  You will especially have to do so if you choose to change string gauges -- straighten the neck more for higher gauges and add more relief (bend) for lighter.  

Unfortunately, you can't make the intonation adjustments like you can on an electric.  When I was at the repair shop last, the guy in front of me was asking just this question, which prompted the repairman to start making jokes about how guitars make good kindling.  He did say that you can play around with the gauges for each until you find the best intonation for that guitar, but that's a lot of work and money.  If you play acoustic, you just have to learn to live with it's little inconsistancies, until they build a better animal.

Further adjustments that can be made to an acoustic are in the nut and the bridge.  You are better off letting someone who knows what they are doing (definitely not me) handle this.  Occasionally nuts need to be replaced due to damage or wear.  Bridges can be shimmed (lowered) or raised.  

When I bought my Taylor years ago, I took it into the shop for it's free adjustment.  The first thing the guy did was raise the bridge action.  When he handed it back to me, I almost cried because he just ruined the reason I forked over so much money -- the perfect low action for my very small hands.  Fortunately, he was able to remedy it in a few minutes and return it to me as I had bought it.  Whew!!!

The other thing to watch for is worn frets.  Again -- this requires major technical know-how.  But it is something to watch out for.  If you have buzzing on certain frets or even notes that don't change from fret to fret, often the cause is some frets have worn more than others.  Usually, the repairman can just file a bit on the surrounding frets to bring them all back into play, but if it's really worn, then sometimes all or some of the frets will have to be replaced.  Personally, I've never seen this, but I've read about it.  Seems to be more common for people who play very aggressively and are especially  fond of the first position.

I bought a banjo a bit back and during the first week I really noticed that any sort of vibrato or bend was really rough.  I had played another one of the same brand in a different store than I bought it in, so I knew it didn't have to be that way.  Turns out that vertical grooves had somehow been etched into the frets.  the guy told me he really had to polish those things, but now they play awesome.  We still don't know they got there, but I do know that you have make sure you don't steel wool over the frets when you clean the fretboard, because that can cause such problems.  

Hope some of this helps. :)

Acoustics and electrics require the same set of adjustments (besides pickups of course), but some things are much harder to adjust on an acoustic.  Action and intonation require a change to the shape of the bridge saddle, and intonation can't be adjusted much that way.  The neck can't be so easily adjusted if it's at a funny angle since it's glued on rather than bolted.  Some electrics, such as the Les Paul have the necks glued in (set neck) as well.

Thanks SLOTHROB for backing me up there, I missed the individual string adjustment bit for the bridges with individual saddle adjustments, was foced on the standerd wood type floating bridge like I have on my guitar. Thanks for covering that part. Together we may have helped the guy some.

Good points all you other guys made also.

Hi. I don't know about the tape measure thing... it sure does sound neat
I think I saw someone doing that once somewhere...
Uhh... In the old days I had a bolt-on neck, We used to take off the
necks and use folded paper as a shim. Notebook paper worked best
because you could fine tune the layers better.
LOL i'm left handed. I used to put aluminum foil in the nut at the
B & G strings to get rid of the buzz I got from switching a right handed guitar
over. You know the foil looked crappy, but man it gave off good
sustain.

The Guitar I have now is a semi-hollow body, the only way i can adjust the action on it is the bridge. I'm just glad the place I got it from knew what they were doing, it's set-up just right for me :)

You can't accurately set intonation with a tape measure. Since the saddle adjustment also has to compensate for the increase in pitch caused by stretching (while fretting), the location that makes the twelvth fret equidistant from the nut and saddle is not necessarily the spot that makes the guitar play in tune. A tape measure can only be used to get a very rough position.