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PostPosted: Mon Jan 25, 2010 7:49 pm 
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Brazilian Rosewood
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Todd...Nice setup indeed. How much % weight loss are you getting once the boards have moisture equilibrated back to ambient conditions?

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PostPosted: Mon Jan 25, 2010 8:46 pm 
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What are the advantages of cooking tops? Dimensional stability?


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PostPosted: Mon Jan 25, 2010 9:44 pm 
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Brazilian Rosewood
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That's pretty cool Todd. I'm also interested in the weight loss right after drying and a few weeks later as the wood re-hydrates. I bought a used oven for about the same $$$ but it takes up a hell of a lot more space.
TJK

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PostPosted: Mon Jan 25, 2010 10:15 pm 
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Brazilian Rosewood
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Here's the one I built. A simple ply box lined with Aluminum flashing. The heat source is my heating blanket. I get it to 200*F and once achieved, I heat the stack for 2-3 hours. I open the top every 20 minutes to allow steam to escape.

Attachment:
Top Cooking Oven-sm-2.jpg


Attachment:
Top Cooking Oven-sm-3.jpg


It will be interesting to know if there is a difference in weight loss between the 2 methods.


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PostPosted: Mon Jan 25, 2010 10:26 pm 
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Brazilian Rosewood
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Luthiers are the most innovative guys I've run across. That's cool JJ

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PostPosted: Tue Jan 26, 2010 12:31 am 
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Brazilian Rosewood
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I might add the dehydrator to get the extra punch. Thanks for posting.

How far does the dehydrator extend inside of the box? What's the circle radius? Do you dehydrate fruit & beef when not in use as a wood dehydrator??

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PostPosted: Tue Jan 26, 2010 8:48 am 
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Brazilian Rosewood
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Perfect...I'm off to Ebay!

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PostPosted: Tue Jan 26, 2010 9:17 am 
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Todd, can I ask why the dehydrator - are you using the unit as a drying kiln as well as to cook your tops? (I am familiar with the concept of cooking tops)

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


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PostPosted: Tue Jan 26, 2010 9:35 am 
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Koa
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What about cooking backs/sides?


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PostPosted: Tue Jan 26, 2010 10:14 am 
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Brazilian Rosewood
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Todd Stock wrote:

Ross Gutmeier (a great Baltimore-based classical and flamenco builder) does the longer, slower cook, and the difference between what happens to sap pockets is interesting...on a 200 degree cook, an open sap pocket will melt and flow out or turn into a solid mass...on a 150-155 deg cook, the resin crystalizes into a powder. This tells me that there is at least some differences between lower and higher temp cooking, but I don't know how this translates to changes at the cellular level.


That's why I'm interested in comparing % weight loss between the 2 methods. My first trial will be to heat a stack of spruce at heat alone (3hrs @ 200*) and compare it to the paired bookmatched 2nd stack using the dehydrated longer, lower temp cycle. The weight loss and stiffness change should begin to shed more light in the issue. As always, it will probably generate more questions than it answers but at least we'll know just a little more.

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PostPosted: Tue Jan 26, 2010 10:50 pm 
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Todd Stock wrote:
Pulled the tops out, and did some of the numbers. The adi tops I had were new, and the vendor suggested some seasoning before use, so I was not surprised to see an average 6.4% decrease in density between unbaked and baked...we'll see what happens after 12 hours, but I suspect we'll end up at about a 3% decrease. Still need to do the deflection stuff, but it seems a bit stiffer (or maybe just as stiff, but lighter, which feels 'stiffer'). BTW, one of the tops have a little bow which seems to have vanished after the bake cycle.


Todd,

By "decrease in density" do you mean decrease in weight? Are you using the term density and weight interchangeably?

Ed


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