Help adjusting the truss rod

[shadesofgray]

So. I've managed to completely avoid ever adjusting a truss rod on a guitar, or intonate it but i've really put up learning how to do it for far too long
because some of my guitars really need to be intonated and truss adjusted by now..

Please educate me, what do I need to know?

[EADGBE]

When looking down onto the truss rod from the top righty-tightey, lefty-loosey. Remember to completely slacken the strings before adjusting the rod. As this will reduce the likelihood of damaging it. Also just turn it between 1/8 and 1/4 of a turn. Re-tune and check. And sometimes after an adjustment the results may not be apparent until about a week or two later.

[GM Reszel]

Originally Posted by EADGBE

..Remember to completely slacken the strings before adjusting the rod. As this will reduce the likelihood of damaging it..

Not true with the exception of a problem neck that won't adjust. In 35 years of tweaking I've never broken a rod with tension on and I've really torqued some of them. Not to contradict you eadg but I just want shadesogray to not be skittish. Play with the truss and learn. EAD is correct in the other things - a proper rod does not take much movement to do a lot, which is why you need the guitar strung up and to pitch to determine what your minute adjusting does to the action.

Understand the terms, relief (concave or forward bow) and back (or convex) bow. Convex is bad and will cause a lot of buzzing, paricularly at the first 5 frets. Most people will tell you that a little bit of relief is desirable and a totally straight neck isn't. My simple credo is I like the neck as straight as possible with getting too much buzz.

There are technicalities like how much relief measured at the middle of the neck, etc, I"m not going into that there; I'll let someone else post.

I will tell you that my quick check is to have the guitar in the playing position. You check it in the playing position so gravity won't pull at the neck giving you a false reading. I will reach over the neck and fret all the strings at the 1st with my left index and do the same with my right index at the 22nd (or top fret). Although this isn't always perfect what you are doing is using all 6 strings as a straightedge and you see where the frets fall away to exhibit relief (or the strings are touching the frets, letting you know of a perfect straight or possible backbow). You can also at this time sight down the sides and surface of the fretboard to determine what's going on. A combination of straightedge assessment and eyeball intuition is the art of the whole thing.

Again this is a quickie fix but adjust the truss so there's just a bit of space between the underside of the strings and the top of the frets around the middle of the neck (7-9th). If one were to measure with feelers, this space would be somewhere in the range of .005"-.010" depending on tastes, type of guitar, the quality of the fretboard plane and many other parameters. I adjust mine until that space just disappears for a straight neck.

There's other issues like how to adjust a neck where the truss nut is at the heel, etc. I'll let others chime in and hope this is helpful. I would recommend this as the perfect treatise to the details of setup and trussdom: http://www.stewmac.com/shopby/product/0570

[reeced]

Just to add one small thing - before you start, mark the top face of the truss nut, so you know where you started from.

[9fingers]

If the truss rod is simply stuck & won't move, try to loosen it a bit, just to get it moving. If it stays stuck, don't force it- take it to a tech at that point. Don't be afraid to try though, most are very easy. Make sure you use the right size socket or allen wrench.

[fretshopnj]

Originally Posted by 9fingers

If the truss rod is simply stuck & won't move, try to loosen it a bit, just to get it moving. If it stays stuck, don't force it- take it to a tech at that point. Don't be afraid to try though, most are very easy. Make sure you use the right size socket or allen wrench.

Just to add something. You should always loosen the truss rod before tightening it to be sure it's not stuck, or else it may be too late when you find out it is stuck.

[Ronsonic]

This is sorta interesting. For many, many years truss rod adjustments were considered outside the range of user service. It was just too dangerous to be left in the hands of a guitar player. Now they throw a wrench in the case along with the keys and warranty card.

Proceed carefully. Take small bites with that wrench allow things to settle before the next adjustment and be perfectly and comfortably prepared to bail on it and hand the guitar to a pro.

Intonation is easier. Actually, it's no easier, just less likely to go wrong. Well, that's not entirely true, either. It's just as likely to go wrong, just nothing gets permanently damaged if you screw up. Okay, nothing expensive gets damaged if you screw it up.

[shadesofgray]

Thanks for all the help! The problem i'm having with the guitar i'm going to try this on, a Fender Custom Shop '62 Limited strat by the way, is that when I hold down the frets on some places I get string buzz

I guess that either means that the neck is too straight, or that the action is set too low (fender does set it very low.)

How do I know if I just need to increase the action at the bridge and re-intonate it or adjust the truss? The guitar has a truss rod-adjustment on the top, aswell as the bottom IIRC

The fretwork is phenomenal so I don't think that's the problem.

I have considered leaving it to a pro, but here in Sweden that means a random person at a guitar store and there's
no way to know if that person is delusional, cares if it's done correctly or just not good at what he does.. I've had to experience all of that in various circumstances

So I figure at the very least I should learn as much as I can about it so that if I have to leave it to a pro, then i'll be able to better determine if they know what they're doing. I really don't want to be reliant on a tech to do something like this though, and i'm willing to spend the time to educate myself on how to do it properly.

[stevel]

Originally Posted by shadesofgray

So. I've managed to completely avoid ever adjusting a truss rod on a guitar, or intonate it but i've really put up learning how to do it for far too long
because some of my guitars really need to be intonated and truss adjusted by now..

Please educate me, what do I need to know?

Personally, I don't like messing with the truss rod, or even saddle heights too much, because I don't have the necessary feeler gauges. I take mine to a tech for that stuff.

Intonation though is not that bad, and something *every* guitar player should know how to fix IMHO.

I'm assuming a bridge with movable saddles here.

Here's what you do:

Tune string. First string to E.

Play string at 12th fret. It should show E on the tuner, and as in tune as the open string.
(note, you can also compare the harmonic at the 12th fret to the fretted 12th fret note)

If the note at the 12th fret is sharp, you need to lengthen the string (move the saddle in the direction away from the nut).

If the note at the 12th fret is flat, you need to shorten the string.

Note though that this is the LAST thing you do - if you change your saddle height, you'll need to fix the intonation. If you change the neck bow, you'll need to fix the intonation. In fact, if you change your string gauge, you need to change the intonation (*really* you should check it with every new set of strings, but usually the margin of error is 'close enough for rock and roll').

Once your guitar is set up properly by a tech, you can make those intonation changes yourself pretty easily.

By the way, my experience has been seasonal changes usually warrant a truss rod adjustment - I had mine checked at least twice a year in the summer and winter.

Intonation of fixed bridge (acoustics, etc.) instruments is a little trickier as it involves shaping of the bridge saddle (you can find bridge saddles with the "corrected G" because of this) and tele owners with the old style saddles have to go through some more drastic measures to get those right.

But if you have an "easily adjustable" bridge system, being able to intonate your own guitar is well worth it.

Steve

[stevel]

Originally Posted by shadesofgray

Thanks for all the help! The problem i'm having with the guitar i'm going to try this on, a Fender Custom Shop '62 Limited strat by the way, is that when I hold down the frets on some places I get string buzz

I guess that either means that the neck is too straight, or that the action is set too low (fender does set it very low.)

How do I know if I just need to increase the action at the bridge and re-intonate it or adjust the truss? The guitar has a truss rod-adjustment on the top, aswell as the bottom IIRC

The fretwork is phenomenal so I don't think that's the problem.

Fender publishes their factory specs at the website.

I find that if I have a tech set mine up to Fender factory specs, it's still "too buzzy" for me. So I just raise the action (increase saddle height) from there.

You might want to tell where specifically you get the fret buzz - I'm sure some of the experts here will be better able to tell you where the problem spots are then.

The intonation is likely going to be off after adjustments, but you want to save that for last to do, because if you make any adjustments to neck relief or action, you'll have to go back and re-intonate. I will add that on a stock fender tremolo system, the bridge plate is usually angled up (not sitting flush with the body) so when you intonate a string by lengthening it, the saddle not only gets further away from the nut, but also come up in height as well (a small amount). So you may have to work back-and-forth to fine tune both elements.

HTH,
Steve

[shadesofgray]

Yeah the bridge has movable saddles, it's a vintage strat-type fender bridge with stamped (brass I assume) saddles

And indeed, the fret buzz has likely been caused by seasons changing. Here in Sweden there's a pretty high difference in humidity between the strong dry winter-season and the humid summer-season

Good idea Steve, I will check which strings buzzes at which frets later tonight when I get back

[walterw]

Originally Posted by shadesofgray

How do I know if I just need to increase the action at the bridge and re-intonate it or adjust the truss? The guitar has a truss rod-adjustment on the top, aswell as the bottom IIRC

nope, it's at only one end or the other.

the idea is to get the neck almost straight, without "going over" (like on "the price is right"). the better the fretwork, the closer to perfectly straight you can get.

tuned to pitch, hold down a string at the first and last fret, and look under the middle frets (like 7-10). the tight string makes a perfectly good straightedge; look for a small gap between the string and the fret, like business-card small. if there's no gap, your rod is too tight, causing backbow. if there's a big gap, the rod is too loose. adjust accordingly.

once the neck is right, then play with saddle height.

(also, those bent saddles are steel, not brass.)

[EADGBE]

Originally Posted by GM Reszel

Not true with the exception of a problem neck that won't adjust. In 35 years of tweaking I've never broken a rod with tension on and I've really torqued some of them. Not to contradict you eadg but I just want shadesogray to not be skittish. Play with the truss and learn. EAD is correct in the other things - a proper rod does not take much movement to do a lot, which is why you need the guitar strung up and to pitch to determine what your minute adjusting does to the action.

Understand the terms, relief (concave or forward bow) and back (or convex) bow. Convex is bad and will cause a lot of buzzing, paricularly at the first 5 frets. Most people will tell you that a little bit of relief is desirable and a totally straight neck isn't. My simple credo is I like the neck as straight as possible with getting too much buzz.

There are technicalities like how much relief measured at the middle of the neck, etc, I"m not going into that there; I'll let someone else post.

I will tell you that my quick check is to have the guitar in the playing position. You check it in the playing position so gravity won't pull at the neck giving you a false reading. I will reach over the neck and fret all the strings at the 1st with my left index and do the same with my right index at the 22nd (or top fret). Although this isn't always perfect what you are doing is using all 6 strings as a straightedge and you see where the frets fall away to exhibit relief (or the strings are touching the frets, letting you know of a perfect straight or possible backbow). You can also at this time sight down the sides and surface of the fretboard to determine what's going on. A combination of straightedge assessment and eyeball intuition is the art of the whole thing.

Again this is a quickie fix but adjust the truss so there's just a bit of space between the underside of the strings and the top of the frets around the middle of the neck (7-9th). If one were to measure with feelers, this space would be somewhere in the range of .005"-.010" depending on tastes, type of guitar, the quality of the fretboard plane and many other parameters. I adjust mine until that space just disappears for a straight neck.

There's other issues like how to adjust a neck where the truss nut is at the heel, etc. I'll let others chime in and hope this is helpful. I would recommend this as the perfect treatise to the details of setup and trussdom: http://www.stewmac.com/shopby/product/0570

A lot of luthiers I trust warn about adjusting the truss rod while the guitar is tuned. As it could strip the threads of the nut. The nut is usually made of softer metal than the rod itself. So that if damage is done it's usually to the nut. As it's much easier to replace the nut than the rod. So to keep from having to replace anything it's best just to completely slacken the strings before adjusting the rod.

[walterw]

Originally Posted by EADGBE

A lot of luthiers I trust warn about adjusting the truss rod while the guitar is tuned. As it could strip the threads of the nut. The nut is usually made of softer metal than the rod itself. So that if damage is done it's usually to the nut. As it's much easier to replace the nut than the rod. So to keep from having to replace anything it's best just to completely slacken the strings before adjusting the rod.

that may be true for problem necks or dodgy designs (ric?) but for the vast majority of guitars that's just a time-waster.

turn the stupid rod until the neck is right, get on with your day.

[VTX-XTC]

You do not need to slacken the strings to adjust the rod. If you had to slacken the strings every time you made a slight adjustment, it would take forever and you would probably break a bunch of strings in the process. The luthier I trust the most, Dan Earlewine, doesn't recommend that. If it was necessary, he would say so. I've been a luthier for almost 20 years myself, and have never had to slacken the strings to make an adjustment....and I've never had a problem.

Make a mark with a Sharpie on the nut to identify the default location. Back the nut off about a 1/4 turn and then, re-tighten. Usually, adjustments needed are 1/8 turn or less. If you have the time, it's always a good idea to back the nut off completely and remove, clean the nut and rod threads, lubricate the nut and rod threads (a little vaseline on a q-tip works great and doesn't make a big mess) and re-install.