finalizing top bracing

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turnertj
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Re: finalizing top bracing

Post by turnertj »

Cool!
Tj Turner
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turnertj
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Re: finalizing top bracing

Post by turnertj »

Hey all...

I have a brace material choice to make, so I thought I would have you weigh in so I can understand the trade-offs better. I made an x-brace yesterday from some Adirondack Spruce. It seems good, but the grain is pretty wide. I also have some sitka with much tighter grain. They appear to be the same stiffness (measured through my scientific bendy test...the use of the word 'bendy' should illustrate how scientific this test is!). Which one would be better for brace material?

Tj
Tj Turner
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Darryl Young
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Re: finalizing top bracing

Post by Darryl Young »

Just my opinion but the one with the least runout and straightest grain would be my choice. Be sure to check runout by splitting both directions as grain running out the bottom or side will weaken the brace........but grain running out the bottom/top is the worst case as it weakens it more in the plane where it needs to provide the most strength.
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tippie53
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Re: finalizing top bracing

Post by tippie53 »

I will be finishing up bracing today and will post the photos later today. There are many ways to make bracing . When I opened my wood I didn't have anything to split as it was ready to go . If you do split , the first split should be across the grain . This will decrease the amount of Runout . Then split with the grain square up and size.
With all that done I rip the brace stock from the largest down to the smallest. I preped 77 sets of top braces in this exercise. All red spruce. I have some 1/4 in and most 5/16. Once sized it then gets rough shaped and radiused. Then the notch is cut.
All my braces are .625 high for the Main X and truss rod. I pretty much use a similar brace like Martin. I will alter some for Gibsons. Dust masks for all . keep and eye out
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
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turnertj
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Re: finalizing top bracing

Post by turnertj »

Hey guys...

I thought I heard mention somewhere of someone not tucking in their x-braces. When I think about the forces the top is under, it seems that tucking the x-brace into the kerfing in the lower bout might not be necessary, or add that much. I can see it being more useful for the upper bout and the brace north of the soundhole.

Comments?
Tj Turner
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Darryl Young
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Re: finalizing top bracing

Post by Darryl Young »

Yes, tuck the UTB and X-Brace in the upper bout. Your choice on tucking in the lower bout.
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Jim_H
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Re: finalizing top bracing

Post by Jim_H »

I tuck both ends of the X's and the UTB.

I wonder what an eperienced repair person would say about the long term plusses and minuses of tucking other braces (i.e. tone bars).

Rick Davis is the one whose example I followed, and between he and Cat Fox, there have been a lot of repairs through his shop. I suspect if there was any significant value to tucking the tone bars, he would be doing it.
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Kevin Sjostrand
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Re: finalizing top bracing

Post by Kevin Sjostrand »

I've always inletted the X braces and the UTB brace. I can not see any benefit to not doing it, and at least I feel some security that it is helping in the structural integrity of the guitar body to top juncture.

Kevin
David L
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Re: finalizing top bracing

Post by David L »

I prefer to tuck the X-braces at the lower bout if for no other reason than it helps me to locate the top to the rim, less chance of a mis-match when I close the box.

David L
tippie53
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Re: finalizing top bracing

Post by tippie53 »

Martin tucks the truss rod and X only on the top the backs , all are tucked. I do it the same way. The braces not tucked I will fade the ends to the top
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
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