My guitar neck is bending forward(20 years of string pressure, no truss rod ajustement. Yeah.). Can this create intonation problem? because as I go up the FB, it sounds offtuned a bit.
Quote by n1ckn1ce
The string heigt at the 12 fret is like 5mm... Is that too much?
That's about 1/5 inch. Arguably it should be about half that. (That's assuming steel strings, not nylon).

The higher the action, the more a string raises pitch (above the intended note),when fretted.

That said, the action should be adjusted by filing the bridge saddle anyway, not the truss rod.

Make sure you have a spare saddle around before you fly into sanding the one in the guitar down. Like they say,,,"s*** happens". (And never for the better, it would seem).
No, the action is clearly raised because of the neck. Cause if I pull it backward, everythings fine.. and I dont want to mess with saddle, honestly.
Well, if the guitar has no truss rod, and you refuse to adjust the action with the saddle, there really very little else you can do.

Arguably the neck could have come loose at the glue joint. Just as likely, the sound board has settled in too far, or the braces have come loose. Take it to a shop.
Quote by n1ckn1ce
It does have a truss, but it doenst seem to work. I tried, believe me.
This is because the truss rod adjustment isn't for your problem.

It seems to be urban legend that you should fly at the truss rod adjustment for intonation and action height problems. Not so!

The truss rod acts solely on the neck itself. It does almost nothing in relationship to the rest of the guitar.

The truss rod adjustment places, (or rather is intended to optimize), a very slight bow in the neck, to prevent string buzzing. You would fret any string at the first and 13th fret, then check for string clearance at about the 7th fret. The string should have just a very few thousandths clearance between it and the fret.

It has absolutely no impact on the neck to soundboard angle, which is the problem you have. That would require the saddle to be filed down for a less severe action height problem. For a very severe neck to soundboard angle problem, the neck must be reset, period. The only other possibility is that the neck to body glue joint has failed.

You can always pull back on the neck of any acoustic guitar, (actually electrics also), and cause the action to become lower, whether it's right or wrong to begin with.
Last edited by Captaincranky at Oct 4, 2011,