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I built this as a commission, although I told the client that it was an experimental build as it was my first 12 string. I did use a lot of information from the Gore\Gilet books including the bracing pattern and bolt on\off neck design. The body is the Gore medium size steel string. I followed a tutorial from Craig Lawrence on the Australian\New Zealand Luthiers Forum for the 2 string per pin bridge. Richard Woods (Woodsy23 on also on anzlf) modified and ran an existing Finite Element (FE) model he had, for 12 strings load, both light and medium (EJ38s and EJ39s). He determined I would need to increase the height of the falcate braces to 10 mm for the EJ38s and 11 mm for the EJ39s. I ended up with 10.5 mm as I wanted to limit the monopole frequency of the top to keep it in the typical SS range. I ended with 175 Hz top frequency (that I may work to lower to 170 Hz). I have a spectrum analysis with strings at the bottom of this post. I did not measure the bridge rotation under load, but it looks good to my eyes.

The top is Lutz Spruce, back and sides Ziricote.
Bridge BRW, Fretboard EIR, Ebony bindings
rosette, Headstock, backstrap, end wedge, heel cap and side purfling are all Koa.
Finish: EM6000 on zpoxy fill for the body and CA fill and Royal Lac for the neck and head stock.

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http://www.Harvestmoonguitars.com

Looks amazing, John !!! Outstanding craftsmanship, as usual in your builds.


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Very cool, on the bracing I'm guessing you laminated carbon between two layers of spruce? Or am I seeing it wrong?

Thanks, The CF is under and over each spruce brace. So I laminate the top -> CF tow -> brace -> CF tow using epoxy.

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http://www.Harvestmoonguitars.com

Congrats on your 1st 12 string John!


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Here is an you tube line with my guitar instructor Rob Hampton of http://www.heartwoodguitar.com/ playing my 12 string

https://www.youtube.com/watch?v=UebH85F4PAU

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http://www.Harvestmoonguitars.com

Really beautiful and such a great mix of woods! Any specific reason for the BRW bridge?

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Sounds just as good as it looks John.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Sounds really nice John - congrats! Did you feel a touch nervous watching that pick flailing so close to your just finished top? He sounds like a great player, but I'd still be nervous without a pick guard

Thanks all for the kind comments! Mike, I have some removable pick guards in the mail. I was not afraid to have Rob play the guitar he is pretty controlled with a pick. I have not tried to play the guitar with a pick.

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http://www.Harvestmoonguitars.com

Thanks Brad, Mike and Colin,



I have a stack of BRW blanks, I like the look and it has good stiffness for its density. Given that this bridge has a layerof carbon fiber and there is another layer of CF under the bridge plate, I could of used a lighter wood like mahogany. In this case I did not mind a slightly heavier bridge as the top is stiffer than I build a 6 string and I wanted to keep the top resonance down.

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http://www.Harvestmoonguitars.com

That sounds fantastic and the look is superb. Good Job.

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EddieLee

I've never been a fan of twelve strings, but this sounds great !!!
I heard lots of them over the years and this is REALLY nice.

Brent

Thanks guys!

Here is a link as the embedded player stopped working

http://www.youtube.com/watch?v=UebH85F4PAU

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http://www.Harvestmoonguitars.com