Truss Rods aren't action adjusters.
Truss Rods aren't action adjusters.
Truss rods aren't action adjusters.
Yes, relief and action both measure the distance between the string and a fret but turning a truss rod when you want to adjust your action is like putting antifreeze in your engine because they are both liquid.
You might feel triggered. Take a breath. Because there's more. Most likely your trusty neighborhood guitar tech misunderstands this. If you want you action raised or lowered and he sets it on his bench and breaks out a trusty 4mm gently grab the guitar, put it in its case and find another repair person.
Relief is the amount of curve in the neck when the first fret is capo'd, the string is pressed at the 12th fret and the relief is MEASURED at the 6th with a set of feeler gauges. It. Must. Be. Measured. This setting is typically around .008. If you start adjusting things without measuring you have no idea whats actually occuring. You cant eyeball this, its too fine a measurement. Our rods adjust opposite of normal, like resos of old, because we need a shorter truss rod slot. Although rare, we aren't the exception. When repair guys are measuring as they go they know what the neck is doing and see this.
If a repair guy cranks on a truss rod and isn't aware the neck is moving the opposite direction, well that just proves that this measurement cant be eyeballed eh? Sometimes when the truss rod is at the max they will finally measure it, find there's "way too much relief" and because they've maxed out the rod there's nothing more that can be done. Except all that relief came from them, the neck is fine, and they've created a freaked out customer.
The relief can usually only be adjusted around another .008 of an inch.That's the thickness of three sheets of paper. And thats at the 6th fret. Because you are curving the neck that measurement gets smaller the further away from the 6th fret you go. So even if you were incorrectly adjusting a truss rod to raise or lower the action, it wont adjust anywhere close to the minimum adjustment of 1/64", which is .016.
To adjust the action of the guitar you have to adjust it at the saddle. ALWAYS. This adjusts the action in a straight line across the whole fingerboard. The "quick fix" of turning a truss rod isn't a fix at all and it's just a way to avoid the work of doing it right.
Here's a video: https://youtu.be/SAgI1MC2Cqs
-Matt