Warning shocking content!

Construction and repair of Classical Guitar and related instruments
SteveL123
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Re: Warning shocking content!

Post by SteveL123 » Sat Nov 04, 2017 1:10 am

Chris Sobel wrote:
Sat Nov 04, 2017 1:01 am
SteveL123 wrote:
Fri Nov 03, 2017 8:43 pm
Alan Carruth wrote:
Fri Nov 03, 2017 7:11 pm
It is virtually impossible to make any significant change in the voice of one of those things by re-working the lattice once it's together. CF is odd stuff; you can cut the layup with a knife in many cases, but it's very difficult to machine, slow to sand, and can't be worked with anything like a hand plane that you'd use for voicing of wooden top braces. The two approaches I've heard about that work are to add mass in selected spots (found by experiment) on the top, or restrict the vibrating area of the top by blocking off areas around the edge.

I've often thought that a lot of these issues could be addressed by making the lattice off the top. It would be fairly simple to add stiffness, and even take a bit off if need be, and you could test the lattice to see whether it was 'right'. You could not, of course, hear the guitar at that stage, but by comparing readings on lattices you should be able to figure out what worked and what didn't, and refine things. A bonus would be that the lattice itself could be made fairly clean, and you would not mess it up much, if at all, gluing it to the top. The drawback, of course, would be that you'd be starting in pretty much at the beginning of the development cycle, so it could take a while for this approach to pay off. OTOH, once you got it, you'd have it.
By "making the lattice off the top", did you mean to put the lattice bracing on the outside? That's really thinking outside the box. It would look radical. Would also require a tall saddle.
:lol:
Was a serious question. Would make voicing the top a piece of cake in comparison.

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Chris Sobel
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Location: Vancouver, WA

Re: Warning shocking content!

Post by Chris Sobel » Sat Nov 04, 2017 1:25 am

SteveL123 wrote:
Sat Nov 04, 2017 1:10 am
Chris Sobel wrote:
Sat Nov 04, 2017 1:01 am
SteveL123 wrote:
Fri Nov 03, 2017 8:43 pm


By "making the lattice off the top", did you mean to put the lattice bracing on the outside? That's really thinking outside the box. It would look radical. Would also require a tall saddle.
:lol:
Was a serious question. Would make voicing the top a piece of cake in comparison.
It would look pretty cool actually...

Chris
CE Sobel Guitars

gjo
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Re: Warning shocking content!

Post by gjo » Sat Nov 04, 2017 6:58 am

Chris Sobel wrote:
Sat Nov 04, 2017 1:00 am
gjo wrote:
Fri Nov 03, 2017 10:44 am
Chris Sobel wrote:
Fri Nov 03, 2017 2:15 am
If you know anything about this style of build you know that the globs of epoxy on the underside of the top are used to voice the instrument, since you can't really modify the lattice after it goes on.
Do you know that for sure or are you speculating?
True. Gobs of epoxy are used to tune the top... David schramm has spoken about this phenomenon in his posts and videos dissecting a Smallman lattice. I am speculating that the “spills” pictured are a combination of those gobs plus the results of vacuum clamping.

I’m sorry if my post was brusk; I am not a lattice fan and I would never leave the inside of my guitars like that, but I think he deserves a fair hearing.

Chris
Thank you, very interesting to know.

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Michael.N.
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Location: UK

Re: Warning shocking content!

Post by Michael.N. » Sat Nov 04, 2017 11:18 am

I think I'll try 'globbing hide glue tuning' on a traditional fan braced guitar. Shouldn't be too difficult to do!
Historicalguitars.

chiral3
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Location: Philadelphia Area, PA / New York.

Re: Warning shocking content!

Post by chiral3 » Sat Nov 04, 2017 12:42 pm

More permanent than the sticky tack method.
物の哀れ

MessyTendon
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Re: Warning shocking content!

Post by MessyTendon » Sat Nov 04, 2017 4:04 pm

Shocking? No way, it's inspiring...his voicing of his instruments is uniquely his...love it or hate it.

Jim Frieson
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Re: Warning shocking content!

Post by Jim Frieson » Sat Nov 04, 2017 5:17 pm

Inside out , I have not seen it on a guitar . But in case of interest , in can be seen in the work of Doug Martin , in his unique and ingenious violins of balsa .

Alan Carruth
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Re: Warning shocking content!

Post by Alan Carruth » Sat Nov 04, 2017 10:14 pm

No, I mean making the lattice separately and then gluing it to the top on the inside.

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Steve Toscano
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Re: Warning shocking content!

Post by Steve Toscano » Sun Nov 12, 2017 12:52 am

Back to the original point......
While the epoxy would be quite difficult to clean up , especially if vacuum bagged.
The titebond or hide glue clumps squeezed out on the plywood is just being slack, that would have taken an extra 5minutes at most to clean all that up.
These clumps on the ply would not be for voicing. Adding a few grams of glue to that heavy plywood structure would make zero difference. The glue on the lattice and soundboard though is another story.

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