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  #16  
Old 12-07-2017, 06:15 AM
Will Kirk Will Kirk is offline
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Originally Posted by charles Tauber View Post
That's one possible variable that might have contributed to the even response.

In the late 1970's Charles Fox made a guitar that had 6 individual bridges, each with its own saddle. He found that it lacked sympathetic resonance between strings, which he attributed to the disjoint bridge pieces.
Gibson tried that before as well around the 1930s. I suspect they didn't continue it because it was more of a manufacturing issue than a tonal one.
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  #17  
Old 12-09-2017, 12:01 PM
murrmac123 murrmac123 is offline
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Originally Posted by murrmac123 View Post
It just struck me ...on the body of an acoustic guitar, there are three, and only three, areas where absolute flatness is required ... on all other areas , curves rule OK ..

A: Most importantly, the surface on the upper bout where the neck heel shoulders contact the ribs needs to be absolutely flat (as of course do the neck heel shoulders) ... unless ... the heel has a parallel contour rather than a "V" contour.

B: The area underneath the glued fretboard extension would preferably be dead flat.

C : The base of the saddle slot should be dead flat.

On the neck, things are slightly different, naturally ..I am only referencing the body of the guitar.
I just now realized that I should of course have stipulated in [A] that I was referencing only dovetail neck joints. ... mea culpa.

Yes, as far as bolt-ons are concerned you can cope and floss for a tight fit even if the mating surfaces are curved opposingly .... methinks it would be a different story with a dovetail joint.

Also , when I said "flat surface" , I was talking specifically about the V shaped area immediately adjacent to the shoulders of the neck heel.... an area going from 2 1/4 " at the top to maybe 7/8" at the bottom. I would think that no matter how rounded the shoulders of the upper bout are, it would be an imperceptible flattening which would cause no aesthetic problems whatsoever once the neck is fitted.
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  #18  
Old 12-09-2017, 01:42 PM
LouieAtienza LouieAtienza is offline
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Originally Posted by murrmac123 View Post
I just now realized that I should of course have stipulated in [A] that I was referencing only dovetail neck joints. ... mea culpa.

Yes, as far as bolt-ons are concerned you can cope and floss for a tight fit even if the mating surfaces are curved opposingly .... methinks it would be a different story with a dovetail joint.

Also , when I said "flat surface" , I was talking specifically about the V shaped area immediately adjacent to the shoulders of the neck heel.... an area going from 2 1/4 " at the top to maybe 7/8" at the bottom. I would think that no matter how rounded the shoulders of the upper bout are, it would be an imperceptible flattening which would cause no aesthetic problems whatsoever once the neck is fitted.
Well, if the dovetail is fully seated in, and you can get sandpaper in there to floss the joint, the joint is then too loose and needs to be shimmed. I found it best to get the neck just a little proud of the top (I didn't glue the fretboard on until after), then back it out a little and floss the cheeks till the neck slides down flush. Then the dovetail is tight AND the heel is coped.
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  #19  
Old 12-09-2017, 02:07 PM
murrmac123 murrmac123 is offline
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Originally Posted by LouieAtienza View Post
Well, if the dovetail is fully seated in, and you can get sandpaper in there to floss the joint, the joint is then too loose and needs to be shimmed. I found it best to get the neck just a little proud of the top (I didn't glue the fretboard on until after), then back it out a little and floss the cheeks till the neck slides down flush. Then the dovetail is tight AND the heel is coped.
I get that, Louie .... my point is that on a dovetail joint, where the neck needs to be pushed down into the mortise from above, as opposed to being pushed in (and pulled out) laterally it is apparent that two mating plane surfaces are much more ergonomically efficient compared to two curved surfaces , one of which ( body) is convex and one of which (neck heel) is concave.
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  #20  
Old 12-09-2017, 03:32 PM
LouieAtienza LouieAtienza is offline
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Originally Posted by murrmac123 View Post
I get that, Louie .... my point is that on a dovetail joint, where the neck needs to be pushed down into the mortise from above, as opposed to being pushed in (and pulled out) laterally it is apparent that two mating plane surfaces are much more ergonomically efficient compared to two curved surfaces , one of which ( body) is convex and one of which (neck heel) is concave.
Well, both concepts are simple, though one is a lot easier. We're not a factory, teaching a single task to an untrained worker. Then again, I had moved away from the dovetail for the mortise-and-tenon a while back and I can't tell the difference in strength of the joint.
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  #21  
Old 12-10-2017, 08:02 AM
ruby50 ruby50 is offline
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here are some images from Paul Hostetter's site - no flats in sight:

http://www.lutherie.net/mandolin.neck.joint.html
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