how does the truss rod works? exactly


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litus
08-13-2008, 12:40 AM
i know i know, rigth = tighet, left = lossey but how does it works?, i mean from the inside
also i have noticed that my truss rod nut is very deep inside(the last month i give it around 1/4 of turn a week to take away the tons of relief my bass had after a truss rod nut change) compared to other bass(wich were the same model) and were seted up(grammar?)
i am going to need to tight a bit more the truss rod when i change bridge and string gauge so i want to know is it safe to keep adjusting the truss rod, cause the last time it was really hard to move it, so can the truss rod nut be really deep? or is it supossed to have a limit?

zeppelinfreak51
08-13-2008, 12:56 AM
It is NOT a majic action wand.

It should only be used to set relief in the neck. This is how much the neck "bends." The general rule of thumb is that a flat neck (set to "0") is bad, a neck with to much relief is bad, a neck with a little relief is good, and a neck in backbow (bent backwards) is the worst.

jazz_rock_feel
08-13-2008, 09:02 AM
^Remember a neck in back bow only comes with a dual-action truss rod. I would strip the nut of my truss before it moved and inch beyond flat.

Anyway, if it gets difficult to adjust, stop immediately. Let it rest for a couple of hours, see where it settled to and then go from there. If you're at proper relief right now with your current gauge and are looking to adjust to a new gauge, it shouldn't be more than a 1/4 turn in either direction to fix it, if any adjustment is needed at all.

The truss is basically a massive metal rod that's supposed to keep your neck from warping. If you tighten it it straightens out and brings the neck with it. If you loosen it it "relieves" (where neck relief comes from) and goes forward not forcing the neck back. The neck goes towards it's natural inclination to curve towards the bridge from the tension. That's basically what happens.

Oh and it should be:
"(last month i gave it around 1/4 of a turn per week to take away the tons of relief my bass had after a truss rod nut change) compared to my other bass which was the same model and was set up."

I think.

litus
08-13-2008, 05:57 PM
i have already waited for 2 days and it is very hard to adjust, so what could the problem be? the truss rod nut is too bottomed down(grammar?)? or is it that the neck is supposed to have that much relief?, because my friend's bass(wich is the exact same model) has almost no relief and it plays perfectly even with the saddles of the bridge really high
any ideas?

PS thanks for the english lesson guys

ccmetz2020
08-13-2008, 10:07 PM
The neck should have just a little bit of relief, how much does yours have?

litus
08-13-2008, 10:55 PM
The neck should have just a little bit of relief, how much does yours have?
i cant measure it right now, but lots of relief, also when i check relief i do in 2 ways,
way 1, i press the 1st fret and 15th fret and check the 8th fret string height, this one is almost where is supposed to be
and 2 way i press the 1st and the last fret and check the 12th fret string heigt, this one is really high, i can lower this withouth turning the truss rod alot
i also checked with my strings really, really downtuned and in that "tuning" the gap ib the 8th fret = none and the neck looked backbowed, but when i checked the 12th fret it was still fairly high.
is this normal?

jazz_rock_feel
08-13-2008, 11:07 PM
When you downtune you release tension. The truss rod is set so that you have proper relief when your strings are pulling it forward so when you release that tension it will pull it back.

The standard relief check is the first fret and then the fret where the neck meets the body (usually the fifteenth on a standard Fender neck). At that there should be about a credit cards width between your eight fret and the string. I've never heard of checking relief at the twelfth fret.

Marcel Veltman
08-14-2008, 03:18 AM
I've never heard of checking relief at the twelfth fret.

Neither have I. Probably because it doesn't make sense. Somewhere near the 14th fret the neck starts to get thicker, and a little higher up it is set firmly into the body. That means that all the neck curvature is between the top nut and the point where the neck begins to slope into the heel. The point defining neck curvature lies half way between the first fret and the last fret above the slim part of the neck, which is nowhere near the 12th fret.

Maybe there's some confusion because the 12th fret lies halfway the scale and serves as an important reference point for other parameters concerning set up.

litus
08-14-2008, 06:31 PM
When you downtune you release tension. The truss rod is set so that you have proper relief when your strings are pulling it forward so when you release that tension it will pull it back.

The standard relief check is the first fret and then the fret where the neck meets the body (usually the fifteenth on a standard Fender neck). At that there should be about a credit cards width between your eight fret and the string. I've never heard of checking relief at the twelfth fret.


When you downtune you release tension i know that, i was trying to see if i really neede to adjusr more the truss rod

The standard relief check is the first fret and then the fret where the neck meets the body (usually the fifteenth on a standard Fender neck)
i wast really sure of this but that how i meassure relief

I've never heard of checking relief at the twelfth fret.
i have, in a youtube video about how to setup a strat(i know is a diferent thing but a truss rod adjustment should work the same for guitar and bass, or at least thats what i thought)
thanks for that info dude!!
i will not adjust my neck until i got the new strings and bridge i will get in 1 week or 2