Advice on a slightly reverse bowed neck

[Nuuska]

Hello

Despite of all said and told - things are still a bit vague for me - but I have a hunch that you might need higher saddle and tightening of the truss rod.

I might be completely out of woods here . . .

Have you put a longer ruler on the fretboard to verify? You said you used a short - 4-inch - piece clicketing along frets - sounds like too much relief to me.

Try w longer ruler.

 

[West R Lee]

Hello

Despite of all said and told - things are still a bit vague for me - but I have a hunch that you might need higher saddle and tightening of the truss rod.

I might be completely out of woods here . . .

Have you put a longer ruler on the fretboard to verify? You said you used a short - 4-inch - piece clicketing along frets - sounds like too much relief to me.

Try w longer ruler.

That, and the OP is determined to use 10's, and there's a whole bunch of deflection in strings that light.

West

 

[Wilmywood]

That, and the OP is determined to use 10's, and there's a whole bunch of deflection in strings that light.

West

I have used 10s on my '72 since new without an issue.

 

[Wilmywood]

Hello

Despite of all said and told - things are still a bit vague for me - but I have a hunch that you might need higher saddle and tightening of the truss rod.

I might be completely out of woods here . . .

Have you put a longer ruler on the fretboard to verify? You said you used a short - 4-inch - piece clicketing along frets - sounds like too much relief to me.

Try w longer ruler.

I was using that short one to ascertain whether there was a reverse bow or not, and there is not until you get to the 12th-15th fret, then it peaks and gets flat. The fact that the short one makes contact on each fret moving up the board means that there is correct direction slight bow in it below the 12th.
This saddle is exactly the same height as the one on my '72. Tightening the truss rod makes the buzz worse, as it bends the neck back, not forward.
Have a close look at the last pic I posted. It is straight down the neck from the bridge.

 

[West R Lee]

I have used 10s on my '72 since new without an issue.

Has anything changed Wil? Has it been exceptionally dry there by any chance?

West

 

[Guildedagain]

Bigger strings can help of course, otherwise get the neck heated, pressed correctly.

 

[Wilmywood]

Has anything changed Wil? Has it been exceptionally dry there by any chance?

West

I don't know what you mean. There is no issue with the '72. It's the '78 I just got that has the issues.

 

[Wilmywood]

Bigger strings.

Nope had 10s on my '72 since new, no issues the guitar has an issue it's not strings

 

[Wilmywood]

Bigger strings can help of course, otherwise get the neck heated, pressed correctly.

It'll go to the luthier Tuesday. Above my pay grade

 

[Guildedagain]

Your neck is defective. Have it heated/pressed, or have a fret level with light strings. Has it been refretted?


I have have flatwound nickel strings on this, and zero effect on the neck.

My anti snag string ends, taken me a while to perfect.

 

[Wilmywood]

Your neck is defective. Have it heated/pressed, or have a fret level with light strings. Has it been refretted?


I have have flatwound nickel strings on this, and zero effect on the neck.

My anti snag string ends, taken me a while to perfect.

The guitar was played for 2 years before the owner died and was in the case ever since, so no, it has not been refretted.
I use a short pair of needle nose pliers and turn my strings the same way after installation and trimming.

 

[Default]

I wouldn't consider the neck to be defective. I am very interested in your luthier's conclusions, though. Diagnosing anything over the web is extremely difficult. It could simply need a setup and a new nut for the 10's. Could be the nut slots are too wide for that gauge.
Anyway, looking forward to the diagnosis!

 

[Nuuska]

One more try . . .

You might try tighten the truss rod a bit AND raising the saddle - with a shim first to try out.

In the picture from treble side I can see the e-string pinhole has been ramped - which is a clear indication of low saddle.

If the neck is straight from nut to 12th or 14th and the fingerboard makes a dive down should really be no practical issue - while quite seldom one plays that high on a non-cutaway guitar.

 

[Br1ck]

As far as "action" which is really relief, this is how I've learned to check it accurately, and it can give you a good idea of an area of the neck potentially causing string buzz.

You simply place a capo on the first fret, and fret the 15th. Then check the distance, provided you have a feeler gauge handy. between the top of the 5th fret and the bottom of the string. That distance should be roughly .005" to '006". From there you can adjust your truss rod accordingly.

What are the factory specifications for acoustic guitar setup?​

String Height (measures top of fret to bottom of string):
Bass-side string height at 12th fret: 3/32"
Treble-side string height at 12th fret: 2/32"

Relief (measures distance from top of fret to bottom of string while fretting the 1st and 15th fret):
Relief at 5th Fret: .005" (a post-it note folded in half is about .005")

We consider these measurements to be a "medium" action height. You should have some room to lower the action from these measurements, but keep in mind that an ultra-low action usually requires lighter playing or adjusted technique to prevent buzzing. Feel free to give us a call if we can be of any help.

Remember that a little bit of tightening or loosening goes a VERY long way, so be gentle. I'll bet the most I've moved a truss rod nut is about 1/8 turn. Also remember to let the neck settle after any adjustment, then check again.

TRUSS ROD LOOSE: When the truss rod is too loose, the neck bows forward. This raises the string height but a slight amount of forward bow can reduce string buzz. Turn the truss rod nut clockwise to counteract this condition.

TRUSS ROD TOO TIGHT: When the truss rod is too tight, the neck bows backward. This lowers the string height and increases string buzz. Turn the truss rod nut counter-clockwise to counteract this condition.

West

I must strongly disagree with your original sentence. Action is NOT relief. Action is determined by the nut and the saddle. A truss rod only affects the middle of the neck and has little to do with the 12th fret where action is commonly measured. Does relief affect action? Sure, but is not the determining factor. No amount of truss rod adjusting can compensate for a high or low saddle. Too much relief and the string won't clear the 12th fret area when you fret the middle of the fretboard. Truss rod adjustment is a final micro adjustment to improve action, not the main determining factor. This may be the greatest misunderstanding in gutardom. I had a guy tell me a guitar he was selling that needed a reset could be adjusted with the trussrod. I told him, ok, do that, and handed it back.

Guitar techs would rather you leave a truss rod alone, as many issues are created by the uninformed. Are truss rods useful? Yes, but Martin didn't have adjustable rods until the mid 80s.

I'm a firm believer in a fret level and crown, in fact my current luthier will not do a setup without one. Cost here is $225, but it is money well spent, and IMHO more beneficial than changing a nut from plastic to bone. Most guitars will develop a hump where the neck meets the body. Frets will commonly need to be filed a bit in this area as well as taking divots out of the frets.

 

[Wilmywood]

I wouldn't consider the neck to be defective. I am very interested in your luthier's conclusions, though. Diagnosing anything over the web is extremely difficult. It could simply need a setup and a new nut for the 10's. Could be the nut slots are too wide for that gauge.
Anyway, looking forward to the diagnosis!

I don't consider the neck defective either. After all, this guitar spent 40+ years in the case, and for all I know it could have been in a non HVAC garage. It also had no string tension, they were all loose, as was the truss rod nut. I think maybe it's got a bit of warp to it, maybe from being in a hot garage in summer and a cold one in winter all that time. I'm going to keep this guitar once it's ready to play, so it doesn't have to have any resale value. I never get above the 12th fret anyway, so a severe filing or even removal of the 14th fret and up wouldn't bother me a bit. I just want to be able to play it without excessive buzz and not spend more than I paid for it making it perfect.

 

[Wilmywood]

One more try . . .

You might try tighten the truss rod a bit AND raising the saddle - with a shim first to try out.

In the picture from treble side I can see the e-string pinhole has been ramped - which is a clear indication of low saddle.

If the neck is straight from nut to 12th or 14th and the fingerboard makes a dive down should really be no practical issue - while quite seldom one plays that high on a non-cutaway guitar.

The saddle on this G37 is precisely the same height as the saddle on my '72 G37, and the break angles are the same. I'm betting dressing the frets in the 12-15th ans up fret area will take care of the buzz.

 

[West R Lee]

I must strongly disagree with your original sentence. Action is NOT relief. Action is determined by the nut and the saddle. A truss rod only affects the middle of the neck and has little to do with the 12th fret where action is commonly measured. Does relief affect action? Sure, but is not the determining factor. No amount of truss rod adjusting can compensate for a high or low saddle. Too much relief and the string won't clear the 12th fret area when you fret the middle of the fretboard. Truss rod adjustment is a final micro adjustment to improve action, not the main determining factor. This may be the greatest misunderstanding in gutardom. I had a guy tell me a guitar he was selling that needed a reset could be adjusted with the trussrod. I told him, ok, do that, and handed it back.

Guitar techs would rather you leave a truss rod alone, as many issues are created by the uninformed. Are truss rods useful? Yes, but Martin didn't have adjustable rods until the mid 80s.

I'm a firm believer in a fret level and crown, in fact my current luthier will not do a setup without one. Cost here is $225, but it is money well spent, and IMHO more beneficial than changing a nut from plastic to bone. Most guitars will develop a hump where the neck meets the body. Frets will commonly need to be filed a bit in this area as well as taking divots out of the frets.

You'll notice I had "action" in quotes? I was referring to what many people refer to as "action", but in actuality is relief. People many times use the terms interchangeably, when in fact, they mean very different things. . When I refer to adjusting a truss rod, I'm not talking about cranking the thing several turns, but in extremely small increments. I've never moved a truss rod nut more than 1/8 turn in a day or two.

Having said that, I've got a couple of guitars with which the ACTION is set so low that they will buzz from time to time with light gauge strings, usually based on humidity. When medium gauge strings are installed on the same guitar, they do not buzz. The point being, if relief is set very low, with low action, the oscillation of the strings can touch frets, and cause buzz. And by the way, there are interviews online in which both James Taylor and Tommy Emmanuel discuss that very setup........right to the point of buzzing, without actually buzzing.

In fact, I've gone to the time and trouble of taking a feeler gauge to check relief (at the 5th), capo applied at the 1st, while holding the 15th, and discovered that medium gauge strings, at least on that guitar, raise action AND relief around .003"-.004" at the 5th. And '003-.004" can be the difference between buzzing and not buzzing.

West

 

[Wilmywood]

I wouldn't consider the neck to be defective. I am very interested in your luthier's conclusions, though. Diagnosing anything over the web is extremely difficult. It could simply need a setup and a new nut for the 10's. Could be the nut slots are too wide for that gauge.
Anyway, looking forward to the diagnosis!

Dropped the G37 at the luthier this afternoon. He had a look at it and said the first order of business is to dress the higher frets to get some of the hump out of them. Then raise the saddle a bit if needed, and go from there.
I told him I wasn't looking for resale value, just a playable guitar.
We'll see what happens.

 

[Guildedagain]

"Could be the nut slots are too wide for that gauge."

A capo instantly eliminates all nut issues.

You need to get over the hump, and if you never play down near or past the body it wouldn't really matter if the frets are thin, as long as they're out of the way.

Possibly the only proper way to fix this is to pull all the frets, sand the wood flat, and re-fret.

Does anybody know what causes these dreaded humps/ski jumps down by the body? It's not uncommon on electric guitars, older ones.

 

[Wilmywood]

You need to get over the hump, and if you never play down near or past the body it wouldn't really matter if the frets are thin, as long as they're out of the way.

Possibly the only proper way to fix this is to pull all the frets, sand the wood flat, and re-fret.

I told the luthier that I didn't care if he pulled all the 13th and higher frets off it as long as I could play it without that buzzing. I never play past the 12th anyway. He thinks a dressing will do it.