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Old 05-18-2018, 04:52 PM
rodmbds rodmbds is offline
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Default Buzzing Top and Bracing Question

Hi everybody! Got another used guitar for a bargain, this time it's a Brazilian Giannini from the 80s.

The guitar is nylon strung an in awful shape, fortunately most of it I can deal with a thorough cleaning.

The only structural issue is a buzzing top, clearly coming from the upper bout treble side. I can hear it when strings are played or tapping the soundboard.

Thing is, I immediately thought it was a loose brace, but I'm not 100%. Now I noticed that gently placing my finger on the area, the buzz goes away and the sound from the strings actually gets louder. Just placing my finger or something on the affected area.

Got me thinking, is it possible to be something else than a loose brace? The top is laminated and it came across my mind if one of the "layers" might be loose, if that's even possible to happen.

I posted pictures, is exactly where there are two darker lines on the top. They're smooth, it doesn't seem the finish is damaged there. On the other hand, the top is bookmatched and it isn't there on the other side.

Also, there are plenty of dings on the bracing around the area. In fact, around both upper and lower bouts, treble side. I wonder if there's anything I can do about that. I don't mean to get it to a brand new condition, just smoother.

Thanks a lot, again! Any help is much appreciated.

Last edited by rodmbds; 05-18-2018 at 05:14 PM.
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Old 05-18-2018, 06:52 PM
JonWint JonWint is online now
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Remove strings. Press on inside and outside of the suspect area and verify if top is delaminated in that area.

If it is, you'll have to figure out to get glue inside the loose area, glue it, and clamp it. I'd probably use thinned Titebond.

Area is already discolored so you could use thin or medium CA but you only get one chance and it would be nearly impossible to undo. Not my choice.

I'm not an experience luthier.
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Old 05-30-2018, 04:48 AM
rodmbds rodmbds is offline
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Thanks for the tip and sorry about the delay in answering back.

I'm gonna keep this in mind, though it was, after all, a loose brace.

Posting two videos to show.

It's funny that while tapping the treble side caused that sound, it was actually the bass which had a loose brace.

It's now glued back in place and the noise is gone.

https://youtu.be/hDF94Ibg8h8
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Old 05-30-2018, 04:49 AM
rodmbds rodmbds is offline
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Oh, inside the guitar:

https://youtu.be/L_7jnRRzu3l
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