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This build is being shown elseware but I figured I'd share here too. Too cool to not, really. Based on the Contreras Double Top where a second soundboard is suspended in the body of the guitar. That way there is no player damping to the actual back of the guitar. So it's a double top in the Manuel Contreras Sr. form meaning 2 tops total, not 2 tops on top.





1st time I baked a top, still kind of makes me giggle to be honest.



Side prep. Had to add some depth as my sides are too thin in width.



Glued with CA and bent carefully to not melt the glue. Had small 1 cm release on one side; reglued, clamped and sprayed with accelerator.






Fancy'ing up the blocks





Cut to size and glued.

TL, I love you, man!



E

Wow, another stunning guitar about to roll off the bench at TL Guitars!

I'm not sure I'm getting this right: double top (like a top with a Nomex core), or a double back? You threw me when you mentioned "...a second soundboard is suspended in the body of the guitar. That way there is no player damping to the actual back of the guitar. So it's a double top in the Manuel Contreras Sr. form meaning 2 tops total, not 2 tops on top." So, is there an additional back, made of soundboard material, suspended above the back?

Dennis

Yeah exactly Dennis. http://www.manuelcontreras.com/index2.html Hit the Models on the bottom, then the 1st class classical concert on the bottom, then you can highlight the double top but it doesn't show anything, but if you highlight the 25th Aniversary you can see the where the idea came from. This bassically uses another top for the back and binds an extension beyond it as a second back, So yes double back really. But Manuel Sr. called it a Double top, Jr progressed his fathers idea (25th Aniv) to the current Double top and that's what I'm going for. I've played one when I was in Spain, and it's Crazy loud. I also played a current 25th Aniv and the 1st one / proto type built by Manuel Sr. Crazy cool idea.

Flying around here. Back top (2nd top) braced and shaved today, marriage strip too. 2nd top Kerfing installed and 2nd top glued in. Crazy, it's guitar #49 for me. Just missed 50!! And it already sounds insane!!! I think I might make more of these.

So I measured where my 2nd top was going to "hover" and drew a line to show you where it's going to live. I cut my kerfing down with the table saw at 1st but then changed over to the edge sander and did it by hand. Once the blade hut the kerfs, if the band wasn't solid enough it just broke the piece away. My sander ripped it down in seconds.




And as most of you know I can't just let the inside of my guitar go with out some tricked-out-ness. So here's the marriage strip. Soooo close to 50!! My new model HD prototype will get number 50!!




The reason I'm building it this way is that, #1 my sides were too thin and #2 I bought a bunch or brace stock from LMI and while I could cut braces out of it I had all of this 1/4" remaining strips that I had no use for except the braces around my sound hole and I don't need 20 pieces laying around. That'd make 40 guitars worth of sound hole braces. So I thought why not try this and use that leftover stock for the back. So in order to use it I thought why not try try the Torres braceing pattern? The classical guys dig it and it works for guitars with not a lot of torque on the tops so why not brace it that way for my reflector top? I broke the center brace for fun. I envision it adding more center deflection but who knows!!



Now to glue it in. The Kerfing is glued in so I have a base for the top to sit on. I used my model R shape template on the top surface to clamp against and I cut top blocks that stand above the sides to allow my clamps have something to push against and not break my glued on purfling and extra Rosewood sides thickness.

Wow Todd, this is very cool! I hope it knocks your socks off when its all done and strung up.

Do you know if anyone building double backs / double tops ever puts a soundhole in the internal top? Maybe that would completely defeat the purpose, but it seems like it also might allow the inner top to move more? Hey, it's !:00am, my brain is in the Twilight Zone...

Thanks for showing this!

Dennis

Interesting concept, it sorta reminds me of the "Tone-gard" that some mandolin folks like to use.

http://www.tone-gard.com/

Hey Todd
Is that top you are showing the inside top? If so, why do you have it braced? If it is inside, It will not be bearing the load of the strings thus being free to vibrate. The outside top would take on the load of the strings and need bracing...or am I completely missing the point here? I like what you're doing, but I guess I need a bit of clarification
Thanks
David