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  #1  
Old 04-28-2017, 09:26 AM
hat hat is offline
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Default dealing with too much neck angle

Other than pulling the neck, and recutting/shimming the dovetail joint, are there other ways to deal with an overset neck? I am wondering if there would be any way to do a reverse 'California neck set' or something similar? I suppose the bridge could be built up, and a new taller saddle made, as long as it didn't cause too much extra stress on the top. Any suggestions?
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Old 04-28-2017, 09:53 AM
dekutree64 dekutree64 is offline
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Measure the bridge rotation under tension to get an idea of how much additional torque it can take (2 degrees is a safe limit).

One option would be a wedge fingerboard (thicker at the nut end, thinner at the soundhole).

But most likely reworking the dovetail is the best bet.
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Old 04-28-2017, 10:12 AM
murrmac123 murrmac123 is offline
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not a problem which you will ever encounter with a Martin guitar ...
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Old 04-28-2017, 10:22 AM
hat hat is offline
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Quote:
Originally Posted by murrmac123 View Post
not a problem which you will ever encounter with a Martin guitar ...
Not true at all! Read this thread...
http://theunofficialmartinguitarforu...2/Overset-neck
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Old 04-28-2017, 12:06 PM
murrmac123 murrmac123 is offline
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Originally Posted by hat View Post
Not true at all! Read this thread...
http://theunofficialmartinguitarforu...2/Overset-neck
interesting thread ... thanks for the link !

I guess if repairmen of the calibre of John Arnold and David Collins testify to the existence of the phenomenon in Martin guitars, then it must be true.

I am thinking that things may have changed however over the nine or so years since that thread was started ... nowadays my impression is that most Martins require resets right out of the box to remedy underset necks.
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Old 04-28-2017, 12:25 PM
Halcyon/Tinker Halcyon/Tinker is offline
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Tom,

Building up a bridge and hiking up the saddle isn't really the best approach.

Tell us more about the guitar. Is it a finished guitar, or one you are building?
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Old 04-28-2017, 12:33 PM
murrmac123 murrmac123 is offline
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As an addendum to my post above, I have to say that it never fails to amaze me how threads on guitar forums re neck resets can meander on and on with nobody ever cutting to the chase , which is ...

A: what is the distance between the soundboard top and the underside of the E string ?

and

B: what is the action at the twelfth fret?

Straightedges laid along fret tops to the bridge are irrelevant ... the two measurements above tell you all you need to know.

I take a very simplistic view ... if the action at the twelfth fret is greater than .090" and, simultaneously, the distance between the soundboard and the underside of the E string is less than 7/16", then the guitar needs a neck reset.

Unfortunately, Martin do not consider string height above soundboard as one of their parameters. IMO it is high time they did.
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Old 04-28-2017, 03:08 PM
Howard Klepper Howard Klepper is offline
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Quote:
Originally Posted by hat View Post
Other than pulling the neck, and recutting/shimming the dovetail joint, are there other ways to deal with an overset neck? I am wondering if there would be any way to do a reverse 'California neck set' or something similar? I suppose the bridge could be built up, and a new taller saddle made, as long as it didn't cause too much extra stress on the top. Any suggestions?
Nix the the so-called "California" neck set--it goes easily one way only. To use it for an overset would mean a lot of work and a likely scar where wood is grafted to the back, and only be done in the most unusual circustances.

Resetting the dovetail of an overset neck requires either moving the saddle (and likely the bridge, too) toward the tail, or shimming the heel of the neck and doing a local refinish of the heel.

What is the current height of the middle strings from the top, and how much higher does the action need to go?

Who is the builder? You?
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Old 04-28-2017, 03:47 PM
murrmac123 murrmac123 is offline
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Quote:
Originally Posted by Howard Klepper View Post
What is the current height of the middle strings from the top,
Your correction does not go unnoticed Howard ... yes, it is conventionally assumed that the "string height" is and should be measured at the D string ...

I am not convinced that this is best practice ... the height at the E string is always going to be greater than at any other string, so it makes sense to me to take the E string height as the datum.
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Old 04-29-2017, 08:47 AM
Mr Fingers Mr Fingers is offline
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Disagree. It is because the E is a likely outlier that it makes most sense to work with the middle strings and establish your standard on that figure. The higher and lower strings are saddle adjustments given a neck set done on the basis of the the core string height, or so it seems to me (= no expert!) anyway.
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Old 04-29-2017, 10:40 AM
Howard Klepper Howard Klepper is offline
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Quote:
Originally Posted by murrmac123 View Post
Your correction does not go unnoticed Howard ... yes, it is conventionally assumed that the "string height" is and should be measured at the D string ...

I am not convinced that this is best practice ... the height at the E string is always going to be greater than at any other string, so it makes sense to me to take the E string height as the datum.
Aren't we all measuring to the bottom (closest to the guitar top) of the string?
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Old 04-29-2017, 02:39 PM
Hot Vibrato Hot Vibrato is offline
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Quote:
Originally Posted by murrmac123 View Post
not a problem which you will ever encounter with a Martin guitar ...
I'e seen several Martins with saddle exposure around .200" - most recently on a D-45 Marquis which needed a bridge reglue. Way too high in my opinion. This accelerates bellying and top rotation, and is therefore detrimental to the health of the guitar.
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Old 04-29-2017, 02:59 PM
Hot Vibrato Hot Vibrato is offline
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Quote:
Originally Posted by murrmac123 View Post
As an addendum to my post above, I have to say that it never fails to amaze me how threads on guitar forums re neck resets can meander on and on with nobody ever cutting to the chase , which is ...

A: what is the distance between the soundboard top and the underside of the E string ?

and

B: what is the action at the twelfth fret?

Straightedges laid along fret tops to the bridge are irrelevant ... the two measurements above tell you all you need to know.

I take a very simplistic view ... if the action at the twelfth fret is greater than .090" and, simultaneously, the distance between the soundboard and the underside of the E string is less than 7/16", then the guitar needs a neck reset.

Unfortunately, Martin do not consider string height above soundboard as one of their parameters. IMO it is high time they did.
Other important variables you neglected to mention are the height of the bridge, and the amount of saddle exposed above the bridge.

Overall bridge height will vary from guitar to guitar. Therefore the final height of the strings above the top should vary accordingly. IMO, the neck angle should be such that the saddle stands about .125" above the surface of the bridge when the action set to a moderate string height. A taller saddle will result in too much torque on the top, and of course a low saddle indicates that the neck is underset.

I will say that it is sometimes advisable to cut down a bridge that is overly tall. 3/8" seems about ideal, and if the bridge is much taller than that, the additional mass could deaden the tone. That said, regardless of the height of the bridge, I feel strongly that 1/8" of saddle exposure is ideal.
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  #14  
Old 04-29-2017, 11:58 PM
John Arnold John Arnold is offline
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An 11/32" bridge and a 5/32" saddle is the usual formula for a Martin. This results in the 'standard' 1/2" string height. A 3/8" bridge may work fine, but in many cases, I think it adds too much weight....particularly if the bridge is ebony instead of rosewood.
Also.......
Not all guitars function optimally with a 1/2" string height above the top....particularly lightly-built Martins from the late-1920's or style-17 Martins with a rectangular bridge. Those may do best with a nominal 7/16" string height. But when the string height gets closer to 3/8", I notice issues with the pick or picking fingers striking the top.
Of course, the amount of overset can vary, but in most instances, it is so slight that trimming the top of the heel is limited to around 0.020". In that case, the amount that the saddle needs to move (if at all) is such that the bridge itself does not need to be repositioned.
On a dreadnought, trimming the heel 0.020" (0.5 millimeters) results in a change of 0.060" at the bridge. It is a 3:1 ratio. That is why a neck reset is so exacting....half a millimeter too much, and it becomes a real problem.
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  #15  
Old 04-30-2017, 08:36 AM
murrmac123 murrmac123 is offline
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Quote:
Originally Posted by Howard Klepper View Post
Aren't we all measuring to the bottom (closest to the guitar top) of the string?
Indeed we are, Howard, and the height from the top to the underside of the E string will always be greater than the height from the top to the underside of the e string , with the intermediate strings between the E and the e showing a consistent decrement in height along the way. FWIW I have just done these measurements on my 0-28VS ; the E string is .451" above the soundboard, and the e string is .398" above the soundboard.

My point is that it would seem logical to me to accept the higher measurement as a reference point for discussing string height rather than the height of the inside strings. Easier to measure as well.

Last edited by murrmac123; 04-30-2017 at 08:53 AM.
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