Acoustic Guitar Setup

Thanks to cheap labor and mass manufacturing in China, there is a surprisingly wide variety of acoustic guitars available for around $100. So what separates these cheap guitars from those costing five or ten times as much? Modern manufacturing can maintain a relatively high build quality, so the extra money mainly goes towards using rare woods and the additional hand labor for precise set-up. It is my opinion that inexpensive guitars sound fine but can be a little awkward to play . With a little time and care though, it is possible to setup one of these inexpensive guitars with the playability of one costing ten times as much. Here are the adjustments that usually need to be made.

Step 1 Adjust the Truss Rod

The truss rod is used to provide counter tension against the strings to keep the neck in the proper position. It is not used for adjusting the action, this is done in later steps at the nut and bridge. The head of the truss rod is accessed at the top of the neck or from within the sound hole depending on the guitar.

To check the tension on the neck, first make sure the guitar is properly tuned. Then place a capo on the first fret and press down the first string at the 14th fret. Now check the clearance at the 6th fret. You should be able to just fit a piece of heavy card stock (index or business card) under the string at the 6th fret. Tighten the truss rod to decrease the clearance. Loosen the truss rod to increase the clearance

The diagram was found at: http://www.taylorguitars.com/global/pdfs/truss_rod_adjustment.pdf

Comments

[fireflyfae]

Thanks for this instructable, it's brilliant, and I kep it bookmarked for a reference now. :)

Do you have any ideas for loose keys? I've got one of those famous cheap guitars where the string loosens as soon as I tighten it, and I'm wondering if it's worth trying to fix up. (Or using as a practice piece for modifications. :D)

[getthim]

Thanks for this. I agree; the neck angle is never mentioned,perhaps because it can be a problem to remedy. Sighting down the neck toward the bridge can give you a pretty good indication of the amount of work needed. Steve

[harley_rly]

great ible! but man why do you use a cheater(capo)?

[tewharau]

 Awesome Instructable.  Excellent detail!

Another thing I have done with the cheap chinese instruments is to sand down the frets and (sometimes file!) fretboard or inlay.  As the price comes down the finish suffers, but the sound can be OK.  Often the mother of pearl inlay is proud of the wood on the fretboard along with glue drips or crummy paint on the fretboard. I usually use a mix of half linseed oil / half turps to rub on it afterwards.

Keep up the good work!

[screenryan]

What's the point of this step?  Doesn't the height of the saddle determine the height of the strings?  If you aren't routing out a deeper channel for the saddle to sit in, how does this affect string height?  I'm confused.
thanks

[buildinganempire]

Thanks for the feedback.  I had another question about this so I decided to include the explanation in the text for step 5.

[LDW]

Nice work - terrific 'ible.

Kudos!

[mauro12mdp]

Does this works for classic/spanish guitars ? and How do I know if the neck es bowed ?

by the way, very useful instructable good job =)  !!

[buildinganempire]

Thanks for the comment.  Some classical guitars are constructed without a torsion rod.  Such a guitar is usually hand crafted and aligned for classical fingerstyle playing.  The typical inexpensive "classical" guitar should have the same adjustments I have outlined though.

[mauro12mdp]

thanks for the reply =)

I'll see what can I do for it.
On the other hand I have a very old acustic guitar wich doesn't have a torsion rod and the neck is slightly bent. I don't know if this has a solution. I'll try to figure it out.
If u have an answer, thanks again =)

[ruurdjan]

Nice instructable. But why did you bother sanding down the bridge if the saddle is higher anyway?

[buildinganempire]

Good question.  When you look at the saddle you see that the strings go over the saddle and then attach at the back of the bridge.  The saddle seeds to rise above the bridge so that the strings angle down to their attachment point on the bridge.  By angling downwards from the bridge, the strings apply enough force to press the saddle firmly onto the bridge.  The job of the saddle is to transmit the vibrations to the bridge, which distributes the vibrations over the guitar body.  If I just sanded down the saddle without lowering the plane of the bridge then the strings would no longer anger downward to their attachment point; the saddle would not have enough force to keep it in place and start to buzz when it vibrates.  Even after I sanded down the bridge I still found it necessary to cut a few grooves behind the saddle in order to further increase the angle of the strings.     

[sergey.p]

Nice tips!
I have to try this with my "low-cost" guitar.