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Brace ends untucked?
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Author:  Todd Rose [ Fri Mar 24, 2006 1:40 am ]
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No doubt there are many opinions as to whether it's a good idea to feather the brace ends on a steel string guitar top down to nothing before they reach the linings, rather than the traditional method of tucking them in the linings. I'm interested in hearing people's thoughts on the structural aspect of this, rather than the effect on tone (not that I'm NOT interested in the effect on tone, of course, or in hearing people's thoughts on that - maybe I'll start a separate thread for that discussion).

I don't have years of guitar repair experience to rely on, but I've heard it said that if the brace ends are not tucked, there's too big a risk that they will start to pull up (come unglued) at some point. On the other hand, there are many guitars with untucked brace ends, including classicals, Kasha-braced guitars, and various steel string guitars built by modern builders who believe that the looser soundboard boundaries are a good thing for sound. Some builders also do not tuck the inboard ends of "tone bars" and "finger braces" into the X, either. With all these guitars out there, are there really gazillions of guitars in repair shops with brace ends needing to be glued back down? Or is it actually a fairly infrequent problem, infrequent enough that if one were to believe there's a benefit to the sound then one should go ahead and do it?

Thanks for your help.      
Author:  Don Williams [ Fri Mar 24, 2006 1:50 am ]
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Todd,
Those who do this do claim that it frees the top to move better. There are also those who feel it can be a b ad thing for the reasons you've stated. The argument against that is that if the brace end is shave down thin, it becomes very flexible. If flexible, it will move with the top and be less likely to come loose for that very reason, should the top sustain a hit in that area. I believe Kevin Ryan may do this with his guitars, but I could be wrong about that.
Author:  Mario [ Fri Mar 24, 2006 2:42 am ]
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What Don said.

If you don't tuck them in, make sure they come to a thin, feather-thin, point, and not at all abrut.

I've repaired a few from the same maker, where the braces end abruptly at the lining; not tucked, not feather, just come down to about 1/8" and stop. They come loose at the same place....

I've never tucked finger braces or tone bracs. Most don't, either.

I strated out tucking the X and transverse brace. Then, at some point, started floating all of them(feathered). I haven't had any problems with any of these yet, but I now tuck everything forward of the soundhole, and float the rest.

To be honest, the tone/power never really changed with any of these, and there are dozens of each.

Many ways to do this one...
Author:  Michael Dale Payne [ Fri Mar 24, 2006 3:11 am ]
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The only plus I see for tucking with meat left on the brace is to aid assembly alignment. The longer I build the more I lean toward feathering to near zero at the lining (paper thin) on x-brace and to zero on finger and tone bars short of the linings. I still notch for the upper transverse brace but only as an assembly line-up aid.

The top and back, linings, sides and braces expand and contract at different rates. Therefore structurally I think there could be problems with bindings wanting to push away if the guitar goes through major climatic changes due to linear expansion of the tucked brace with substantial thickness left on it. (1/8" or more)

This is a departure from what I did the first few years.
Author:  tippie53 [ Fri Mar 24, 2006 4:43 am ]
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     Actually CF Martin only inlets the truss rod and the X braces. All the other braces are feathered. I have not tucked a brace other the the X and truss for years and never had a problem. In reality , the cedar kerfing has very little strength and is there more for the glueing surface so I don't thinkg the tucking is adding much strength at all and will tighen the top.
      On tucking braces into the X. This was done alot in the older days when glues were not as strong as todays. I think it was done as a mechanical hold along with the glue but I prefer to butt glue the finger braces and such.
   Just one luthiers opinion.
john hall
blues creek guitars
Author:  Mario [ Fri Mar 24, 2006 4:46 am ]
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A truss rod is a brace, now?
Author:  tippie53 [ Fri Mar 24, 2006 5:41 am ]
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Okay Mario
the transverse brace in front of the truss rod
Author:  L. Presnall [ Fri Mar 24, 2006 6:00 am ]
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Are we talking top braces only, or is this good for the back too?
Author:  Alan Carruth [ Fri Mar 24, 2006 10:15 am ]
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What Don said: if the brace has any height at the end it won't want to bend with the top, and the glue line will peel loose. Like Mario, I've repaired too many of these to doubt.

The cedar liner may be soft, but it still provides some support. The big problem is when something knocks the top right over the brace end, and the shock causes it to peel. It doesn't take much to keep the brace and the top together, but it has to be there. Thus what's important is the depth of the pocket, not the width. I can't see how a gap along the side of the brace will make any difference in the strength, however sloppy it might look.

Fred Dickens used to feather all of his back brace ends down, and claimed it made a measureable difference in the sound.
Author:  Todd Rose [ Fri Mar 24, 2006 1:54 pm ]
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Thanks, Don, Mario, Michael, John, and Al, for your replies.    

So, then, if you don't tuck the smaller braces under the X, is it advisable to feather those down to nothing as well, rather than leaving some height on them where they butt against the X?
Author:  Martin Turner [ Fri Mar 24, 2006 3:02 pm ]
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[QUOTE=tippie53]   Okay Mario
the transverse brace in front of the truss rod
[/QUOTE]

Upper Transverse Brace (UTB) in alot of literature.
Author:  Alain Desforges [ Fri Mar 24, 2006 3:18 pm ]
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I don't know if it will help at all, but I've put West System Epoxy (with silica to thicken) in every pocket along the soundboard kerfed lining. My braces all feathered down to nothing. I figured if something was going to rattle and hum, I was going to change it's mind from the get go...
Author:  L. Presnall [ Sat Mar 25, 2006 2:51 am ]
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So how about the back braces?
Author:  Todd Rose [ Sat Mar 25, 2006 12:19 pm ]
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[QUOTE=L. Presnall] So how about the back braces?[/QUOTE]

Al mentioned Fred Dickens, above, who feathered his back braces down.

I'm still wondering if you guys think it's a good idea to feather the finger braces and tone bars down to nothing where they meet the X, if you're not going to tuck them. It would seem that the same risk of coming unglued would apply there, too, no?
Author:  Alan Carruth [ Sat Mar 25, 2006 12:34 pm ]
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"I'm still wondering if you guys think it's a good idea to feather the finger braces and tone bars down to nothing where they meet the X, if you're not going to tuck them. "

That's what I'd do. I tuck them, myself, for the most part. In fact, in my 'double X' braced tops the lower X and the finger braces are the same pieces of wood: trimmed down to about 2.5mm tall at the crossing with the main X fitted over them. I also take the upper 'A' brace through the shoulder brace, and inlet the lower ends into the main X. The upper ends of the 'A' inlet into an extended 'chin' on the neck block. Overkill, maybe, but I've had a couple of these dropped pretty vehemently, with no top cracks or popped bracing, so I do sleep well o' nights.   
Author:  Lars Rasmussen [ Sat Mar 25, 2006 9:07 pm ]
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"I'm still wondering if you guys think it's a good idea to feather the finger braces and tone bars down to nothing where they meet the X, if you're not going to tuck them. It would seem that the same risk of coming unglued would apply there, too, no?"

Thats how I do it too. Except for the tonebars that I let into the X, someway it feels like they have a better connection to eachother that way. Well, I'll post a picture... This is my first try with this pattern(tonebars/fingers) so its a little experimental.

Author:  Todd Rose [ Sun Mar 26, 2006 11:09 am ]
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Thanks, Al and Lars. Very helpful.
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