Truss Rod Adjustments

[bagpipe]

Truss rods and their adjustments have always been something of a "black art" to me. I'm currently putting together a Strat partscaster and will be slowly tweaking the truss rod to get the guitar feeling how I like it, and using this to learn how adjustments are made. I thought I would post my understanding of the truss rod to see if others can share their tweaking experience.

On my Strat the truss rod adjustment is done at the headstock. I've mainly been following the Fender setup guide here:

http://fender.com/support/stratocaster.php

If I want to increase the neck relief, I loosen the truss rod. On my guitar, this involves sighting down the neck from the headstock, and turning the truss rod screw to the left (counter clockwise). This will allow the string tension to pull more relief into the neck. If on the other hand I want to decrease the neck relief, I tighten the truss rod (clockwise). This will cause the truss rod to become less flexible, and resist the strings from pulling the pulling the headstock, thus reducing the relief in the neck. ???

From what I have read elsewhere, I should adjust the truss rod only 1/4 of a turn at a time and leave the guitar overnight to allow the changes to take place.

I'm guessing that the thickness of the neck (ie how much wood is there) will also have an impact on how the string tension can cause the neck to flex. This guitar has a fairly hefty Warmoth neck (59 Roundback carve).

[fraser]

correct on all counts bagpipe- thats how its done on a single action truss rod.
a dual action does the same thing, but never loosens, it just bends both ways.
yours will likely be single action.
when i first install a neck, using a straight-edge i adjust the neck so that it has just the smallest amount of backbow by tightening the rod.
then once the strings are on it, i check to see how it reacts to the tension, and adjust where necessary. on a new guitar or new neck its not uncommon to have to adjust it several times over the first few months, as it breaks in.

[PaulS]

I agree with what has been said so far. After adjusting the rod a few times the black art syndome will be gone. What I have noticed is some woods seem to be more stable than others when it comes to humidity. My 67 tele has not had a neck adjustment in 10 years, hasn't required it. A few others I have encountered seem to need seasonal adjustments and then some. The older the neck is the less fussing it needs is the way it seems. On a recent telecaster build with shoretyus we used walnut for the necks and I'm finding I need to adjust quite frequently with the weather we have been getting, very damp. Maybe as it ages it to will settle but I curse the vintage style rod install, removing the neck each time is no joy.

[fraser]

From what I have read elsewhere, I should adjust the truss rod only 1/4 of a turn at a time and leave the guitar overnight to allow the changes to take place.

I'm guessing that the thickness of the neck (ie how much wood is there) will also have an impact on how the string tension can cause the neck to flex. This guitar has a fairly hefty Warmoth neck (59 Roundback carve).

forgot about this part- 1/4 turn is a safe amount to advise someone to use, but you kind of feel it- once you feel it getting harder to turn, go easy, or you can break it or strip the nut-
you cant do any damage loosening it tho- only when tightening.
ill tweak the rod until its right, tune to tension and play it. next day or so, it may need tweaking again- but i make no rules on how long to wait or anything.
every neck acts a bit differently to adjustment, so you wont know for sure until youve tried this one.
a bigger neck will provide more stability, but then it also depends on the wood the neck was made from- and how it was cut. you dont hear many folks unhappy with warmoth necks-

i agree with paulS- i find older necks need less tweaking- ive got guitars that havent had a truss rod adjustment in years, and never need it- but they are 15 or more years old-

[shoretyus]

On a recent telecaster build with shoretyus we used walnut for the necks and I'm finding I need to adjust quite frequently with the weather we have been getting, very damp. Maybe as it ages it to will settle but I curse the vintage style rod install, removing the neck each time is no joy.

Funny it's sister ( same block of wood ) hasn't moved a bit. The rod does moved it .. right ? Thinking about truss rod fit. Your slot was just a slight bit wide. They are also quartersawn. Wood moves most across the grain i.e. across the board in a flat sawn piece of lumber. Not much in thickness.

A quartersawn neck is technically flatsawn when looking at it's edge or thickness. If it was to move or expand it would be in thickness. That is directly related truss rod forces. That wood was as dry as possible. It would absorb moisture and increase on size.

Sounds good on paper but my has stayed straight. Wonder how #3 and #4 necks are doing.

[fraser]

Funny it's sister ( same block of wood ) hasn't moved a bit. The rod does moved it .. right ? Thinking about truss rod fit. Your slot was just a slight bit wide. They are also quartersawn. Wood moves most across the grain i.e. across the board in a flat sawn piece of lumber. Not much in thickness.

A quartersawn neck is technically flatsawn when looking at it's edge or thickness. If it was to move or expand it would be in thickness. That is directly related truss rod forces. That wood was as dry as possible. It would absorb moisture and increase on size.

Sounds good on paper but my has stayed straight. Wonder how #3 and #4 necks are doing.

perhaps its just a bit of difference in the sum of its parts? are they both rosewood boards? maybe pauls board and join with the neck is still stabalizing, or was a bit different in some way? or maybe theres a difference in the fretwire or string gauge?
i have a 2 year old acoustic that felt different every time i picked it up. was tweaking the truss rod constantly. about 6 months ago i picked it up and wow, i had been ready to give up on it, but suddenly the neck was dead straight, action perfect, plays like a dream- and its still like that now with no adjustment. somehow it just settled into exactly what id been telling it to- and stayed there.
necks are funny things-

[PaulS]

It may settle with a bit of age, but it is small adjustments made. I can get it to come to where I want it then need to re tweak a few days later. It has been a damp summer so far that may have some effect on it. Fret wire was 6105 on two of them not sure what the first was. I wonder if this is why a majority of necks seem to be maple.

[shoretyus]

It may settle with a bit of age, but it is small adjustments made. I can get it to come to where I want it then need to re tweak a few days later. It has been a damp summer so far that may have some effect on it. Fret wire was 6105 on two of them not sure what the first was. I wonder if this is why a majority of necks seem to be maple.

I think maple because of the density/hardness factor. A neck is really a small piece of wood under a lot of tension. Tougher the better. It is also common to have quartersawn maple necks. But walnut and mahogany are pretty close in density and strength and gee can we think of any brands that use it for necks?

The other factor is one is a all walnut body. Maybe it's moving more than the Cocobolo/Walnut body.

This make a case for milkman's plexi Less Paul ? tee hee

Speaking of necks:smile: I am hoping to get pickups in my mailbox today.

[smorgdonkey]

Your slot was just a slight bit wide.
Don't let his slot hear you saying that.