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I hope that title made you a bit curious.

I was thinking back to my building course I took with de Jonge about 1 ? years ago and rememberd something he mentioned. He said that if he received some wood that wasn’t sure was dry enough to use he would “cook” it in the oven on low for several hours to speed up the process. I think he even did this while I was there. This was a while ago and I can’t remember the guidelines doing for this.

Is there anyone out there who has done this? Or am I crazy?

Josh

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Josh House

Canadian Luthier Supply
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Not in oven. I do measure wood say at seam and then put it in a kiln. This is just a space heater of about 100 degree's in a little locker I made and for about an hour. Sometime there is a little shrinkage. Don't know if really nessessary, just something was taught at Galloup and do.

I visited w/ Don Gallagher back in the mid 70's and he was doing this very thing. In fact, he made it a regular part of his building schedule. Of course it wasn't the family stove that he had hauled over to his shop, but a dedicated vertical cabinet-thingy that was cooking his wood.
Whether he still does this now- or not- I've no idea. But his guitar (that I bought from him) is the most stable guitar I've ever seen... or played.

I need a vertical cabinet-thingy, I guess.

Steve

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From Nacogdoches...the oldest town in Texas.

http://www.stephenkinnaird.com

Cool rosewood souffle', and spruce kabobs!

Guys here's a link to a discussion about "Cooking Spruce". William Cumpiano is involved along with a few other really knowledgable luthiers. Interesting reading if your curious-----Snick
http://luthierforum.com/index.php?showtopic=512&hl=

Collings does it, as well as many, many others, myself included. Most 'cook" at 200 or less for any hour. Pulls all the moisture out and sets the pitch.

You don't want to go over 200, as you'll risk breaking down the lignin.

But y'all knew all this already.....

What are the units there Mario? C's or F's? I'm assuming degrees F, 200 Centigrade seems a little toasty. But you're in Canada where you use the metric system, so I'm unsure.

Thanks guys. It nice to know I'm not crazy (although I have been told that I am crazy to think I'm ever going to make money building guitars).

So you wood cookers
Do you cook the back and sides as well as the top? I think I would have to cut the sides in half to get them to fit in my oven. I really like this idea and think I will give it a try with the tops to start with. Eventually it would probably be a good idea to build a vertical cabinet-thingy like Steve has. But for now the kitchen stove will work nicely.

Paul
Mario is using F's. 200 degrees F is about 95 C. It can be a little confusing with the 2 systems of measurement. I tend to go with whichever one is more convenient for the task at hand.

Josh

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Josh House

Canadian Luthier Supply
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House Guitars - Custom Built Acoustic Instruments.
http://www.houseguitars.com

back and sides. Get or build a cabinet for what you want. You can get space heater with thermostat really cheap. Just set it for 100 to 200 and let it set in there about an hour. Be careful about getting an old gas stove as they havae flames in the oven portion and flame with wood, well not a good thing. Cheape and easy to build a little thing in shop. May not even need a cabinet just set up with a heater let it blow heat onto wood

No need to do the sides in an oven; you're going to cook 'em when you bend them. Sheesh...<bg>

I only do the tops. I believe that Collings and others only do tops, too. Before you join them, if that wasn't obvious.

I may live in Canada, but I'm not metric. I measure in inches, drive in miles, and live in a house that is 70 degrees. You can lead the horse to water, yadda-yadda-yadda.....

200f.....

Mario - is this standard protocol for your tops?

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Take up putting sides and back up with Galloup, they make pretty nice guitar and that is what teach. Sheesh. Not all of us exit the womb, with a chisel and full knowledge of building guitars

is this standard protocol for your tops?

Sometimes.... Most of them, I guess. It's something I've done on and off forever.

I have nothing to take up with Brian. I have not heard of anyone cooking backs and sides, though I'm sure some do, but in any case, the sides will be cooked when you bend them, so pre-cooking seems like a waste of time, and if anything, could make the wood brittle. The backs can go in your home's oven with the tops. Or as you say, a box with a handful of bulbs and a dimmer to control the temp will do. The box needs to be vented, to allow moisture to escape, same as your oven is vented.

An oven with just the light on and the door held open about an inch makes a nice, low temperature kiln, too. Holds about 100 degrees all day that way.

Collings uses a convection oven... Mine's a Maytag(or something) <g>

Mario, I apologize for the rude comment. You have forgotten more than I know. Good idea on the sides and one I hadn't thought of. Just a really bad day and no where to release some of the frustrations, but here isn't the place. Again sorry
Stan

Hey thanks so much everyone. This has been most helpful.

I will be giving this a try on my next batch of guitars which I will probably be starting in about 1 month.

Josh

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Josh House

Canadian Luthier Supply
http://www.canadianluthiersupply.com
https://www.facebook.com/canadianluthiersupply?ref=hl
House Guitars - Custom Built Acoustic Instruments.
http://www.houseguitars.com

I have "cooked my wood" in the oven and when my wife found out she was mad! Kidding...(about the mad part). Anyway, I once bought a real beautiful Flitch set of super curly KOA from Todd at Alied. Hand picked it...shipped it home. Well thanks to UPS when it finally arrived back in FL the box was soaking wet and torn and of course the wood looked like a pretzel. Called Harry Fleishman and he suggested I bake the wood between two pieces of 1/4" aluminum at about 300 degrees after giving it a real good spritzing with de-ionized water. Then he said wet it again after the bake and let is sit under something heavy for about a week or two...( i put it under my living room table which is solid and heavy)...two weeks later...Good as new...Still have it stickered 2-3 yrs now and still straight as an arrow! I never thought to try and dry green wood that way but I guess it would work as Mario can attest to!

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Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"

Along the same lines as what Dave described, I have straightened a warped rosewood fingerboard blank in the kitchen oven by clamping it between two pieces of heavy steel flat bar. I brought it up to around 300°F and let soak half an hour or so, then turned the oven off and let it cool slowly.

Last week I used the same method to flatten a purpleheart ukulele fingerboard that developed a stiff back bow after fretting. Now it lays flat. TomS38441.531400463

I know that Dana Did it a time or two when I worked at pantheon for
special projects. Worked well!

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John Mayes
http://www.mayesluthier.com

[QUOTE=Dave-SKG] I have "cooked my wood" in the oven and when my wife found out she was mad! Kidding...(about the mad part). Anyway, I once bought a real beautiful Flitch set of super curly KOA from Todd at Alied. Hand picked it...shipped it home. Well thanks to UPS when it finally arrived back in FL the box was soaking wet and torn and of course the wood looked like a pretzel. Called Harry Fleishman and he suggested I bake the wood between two pieces of 1/4" aluminum at about 300 degrees after giving it a real good spritzing with de-ionized water. Then he said wet it again after the bake and let is sit under something heavy for about a week or two...( i put it under my living room table which is solid and heavy)...two weeks later...Good as new...Still have it stickered 2-3 yrs now and still straight as an arrow! I never thought to try and dry green wood that way but I guess it would work as Mario can attest to! [/QUOTE]


Dave how long did you cook it? I have a set of walnut sides that could use a trick like this.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

Brock,
it was a few years ago but if memory serves correct I believe it was for about a half an hour or so...I would pay close attention to smell...you don't want to burn it up! Harry also told me to bake it several times if need be, spritzing it down in-between bakes. It works incredibly well! Once was enough for the KOA. But remember I also kept it under pressure for two weeks, between two sheets of aluminum. Also, check the wood every so often while under pressure...you don't want to get any mold growing...I checked it maybe every other day.

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Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"

I wonder if this would work for my pretzeled back. I'd have to take the braces off.

Pretzeled back sounds like a shift in humidity post-gluing to me. I'd wager it would flatten out again almost on its own when you carve the braces off. If it was flat and stable to begin with, anyway.

There is an old rule of thumb in chemistry that a 10 degree centigrade change will double the speed of a chemical reaction. If the change over time of a piece of wood is due to a reaction like oxidation, then after 2 days in an oven set to 85C (room temp + 60c) 6 time doubles should take place. Or those 2 days in the oven are like 64 days of elapsed time. One year in the oven would make 30+ year old wood. This is of course pure speculation about why baking might make the wood seem to improve and simulate "old" wood. Questionable science but interesting anyway. a link to further reading about the "science" http://antoine.frostburg.edu/chem/senese/101/kinetics/faq/te mperature-and-reaction-rate.shtml

We don't 'cook' the wood to make it magically become vintage(though that would be cool!). It doesn't seem to change the tone one bit.

What it does is make the wood more stable, and much less prone to cracking. Wood shrinks when it is dry. Quarter sawn wood shrinks a lot when it is dry. But it also never regains it's full dimensions once humidified again. So, by taking it down to its minimum dimensions be drying it completely, it is, in effect, 'pre-shrunk'. That means that it is less likely to crack and split in its first dry winter. Also means it should move less with the seasons.

That settles it. I'm gonna be cooking the next few, just in case. Besides, I suspect warm Western Red Cedar will lend a pleasent aroma to the room while it's cooking, even at a relatively low temp..