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Old 06-11-2016, 09:59 AM
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Bruce Sexauer Bruce Sexauer is offline
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The dual purposes of the rosette, leaving decoration aside, are both enhanced by having it deeper rather than shallower.

One is to seal the end grain against too rapid a movement of moisture in variable humidity, and the rosette can o ly do this to the degree that it penetrates the top. 5/6ths is my nominal goal.

The other is to stiffen the soundhole lip. Any flexibility in the soundhole lip can introduce distortion and therefore unevenness to the sound of the guitar.

This may appear to be a small thing, but it is a series of small things that add up to the difference between mediocrity and greatness, usually. There is very little in the design of a guitar that does not have a purpose beyond aesthetics.
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  #302  
Old 06-11-2016, 10:59 AM
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Quote:
Originally Posted by Bruce Sexauer View Post
The dual purposes of the rosette, leaving decoration aside, are both enhanced by having it deeper rather than shallower.

One is to seal the end grain against too rapid a movement of moisture in variable humidity, and the rosette can o ly do this to the degree that it penetrates the top. 5/6ths is my nominal goal.

The other is to stiffen the soundhole lip. Any flexibility in the soundhole lip can introduce distortion and therefore unevenness to the sound of the guitar.

This may appear to be a small thing, but it is a series of small things that add up to the difference between mediocrity and greatness, usually. There is very little in the design of a guitar that does not have a purpose beyond aesthetics.
Excellent points, Bruce. For exactly the reasons you bring up, though, I often wonder why it has not become a routine convention for builders to bind the soundhole. To my way of thinking, adding a nice, thin ring of rosewood or ebony to bind the soundhole will seal the end grain, add a protective barrier on that soft wood against the onslaught of picks and fingernails, and also add a subtle visual embellishment that can complement the design of the rosette.
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  #303  
Old 06-11-2016, 12:24 PM
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Originally Posted by theEdwinson View Post
Excellent points, Bruce. For exactly the reasons you bring up, though, I often wonder why it has not become a routine convention for builders to bind the soundhole. To my way of thinking, adding a nice, thin ring of rosewood or ebony to bind the soundhole will seal the end grain, add a protective barrier on that soft wood against the onslaught of picks and fingernails, and also add a subtle visual embellishment that can complement the design of the rosette.
I have bound soundholes in the past, and have seen plenty of other examples as well. The reason(s) I do not do it are several.

It is quite challenging to get the ring in there tightly enough to make a solid contact.

If the ring is too tight, it will pressure the top to split.

Because of variations in humidity, the ring will vary between too tight and not tight enough, leading to glue failure or splitting.

Only a small amount of the ring to top glue join is grain aligned enough to create a meaningful bond, the remainder is to one degree or another an end-grain join, which is tantamount to no join at all.

It is possible to leave a small ledge of top under the ring which solves the long term proximity issue, but then no longer seals the end grain and is fragile, splitting off pieces of top if whacked.

The solution I (and many others) choose solves all of these issues EXCEPT for the last 1/6th of the top sealing, and is not very fragile because the rings are captured in a sandwich, and the potential weakness of the nearly severed top is supported from the inside by the invisible (from the outside) support struts glued to the inside of the top. These struts further stiffen the soundhole edge, by the way, being themselves dual purpose. Or tri-purpose, as they can also be used to resist deformation of the top which contributes to the eventual need for a neck reset, in some design concepts.
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  #304  
Old 06-12-2016, 06:48 AM
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Hi Sir.... my respects. You are a gifted person, a real artist. I've been watching this thread since post #1 and I am really impressed with your art. Thanks for sharing your knowledge and story.
  #305  
Old 06-12-2016, 02:19 PM
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These kind words in the previous post will be a fine way to end the first installment of the Sexauer Saga in 2016. I will start a new thread on my next post, and call it Sexauer/'16 (chapter 2), and link it to its name. (AND I DID!)

Meanwhile that may not be for a week or so as I am packing for my next California Bluegrass Association (CBA) promoted Grass Valley BlueGrass Festival (GVBF). What is special about this event, aside from being the largest Bluegrass event west of the Rockies (last I heard), is the "Luthier's Pavilion".

The event takes place on the Nevada County fairgrounds in Grass Valley, and there is a +/- 4000 sq' building which is dedicated to luthiers, their work, instruments for sale, and repair/set up, which for the four days is referred to as the "Luthier's Pavilion". I have been participating in this for over 20 years (23?) and expect to see over 20 of the peers again this year. The Pavilion is open to the public Thursday June 16 through Sunday June 19 from 9 till 7, more or less. Regulars participants you might know include; Roger Siminoff, Michael Lewis, Randall (Sparky) Kramer, and a relative newcomer, Ben Wilborn. This year the organizer baton has been passed from Michael Lewis to Monte Hendricks, a banjo maker. Monte has been there longer than I have, so I expect a smooth transition.
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Last edited by Bruce Sexauer; 06-12-2016 at 06:06 PM.
  #306  
Old 12-22-2016, 07:23 AM
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Past the 300 post limit. Please start a new thread if you need one.
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