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tattwo
12-20-2010, 04:51 PM
What should the moisture content of wood be before you use it in a build? Is there a cheap meter on the market that works well? Or is there another way to tell.

Thanks Terry

mzuch
12-21-2010, 05:05 AM
Terry, Although I'm pretty new to this, I've been doing a bunch of research as I collect tonewood from various sources for future builds. My understanding is that you want moisture content to be in the 6% to 10% range before you build, depending on your location and shop environment. I use a cheap moisture meter from Harbor Freight which seems to work as far as I can tell. It gives consistent readings, so even if it is off by a percentage point or two I know which sets are drier than the others.

As I learned just yesterday, it is important to sticker wood as soon as it arrives so it can acclimate to your shop without warping, cupping or twisting. I received some nice koa in the mail from Hawaii and it started to cup as soon as it came out of the package. I stickered it and wrapped bungee cords around the pile to keep the pressure on, and I'm hopeful it will flatten out as the wood's moisture content adjusts to the NY winter climate.

Hope this helps. If I'm incorrect due to noobiness, I hope someone will set me straight (pun intended).

Michael

tattwo
12-21-2010, 05:22 AM
Im doing the same thing as far as collecting wood and resawing some while its still a bit wet. I was hoping resawing it wet would speed the drying a little.

Thanks for you input Michael. I will check out Habor Freight. Ive been finding wood local for cheap but its still wet. I enjoy the hunt :)

Moore Bettah Ukuleles
12-21-2010, 06:44 AM
I'm not sure green wood should ever be cut for ukulele sets. You'll wind up with something resembling a stack of potato chips. At the same time I don't like resawing too dry, it takes too much effort. For koa I found that somewhere about 15% is right for my setup. If you must cut green, cut the thickness in half then dry it some more before resawing.
For building, my wood is at somewhere between 6% and 7%. You might be able to get away with it as high as 10% but I think you might be taking some chances. I use a Wagner pinless moisture meter but it's $200. I only bought the pinless type (which is more expensive) because when you are buying wood from someone and measuring the moisture, they don't take kindly to you poking holes in it. Another nice feature of the more expensive models is in being able to calibrate the meter for different species of wood. It's simple to build a dry box/cabinet, any size you want to dry and store your wood in. I keep a small dehumidifier in mine but the same results can be had with a light bulb and a way of keeping the air moving (convection, small fan, etc.)

tattwo
12-21-2010, 07:09 AM
I'm not sure green wood should ever be cut for ukulele sets. You'll wind up with something resembling a stack of potato chips. At the same time I don't like resawing too dry, it takes too much effort. For koa I found that somewhere about 15% is right for my setup. If you must cut green, cut the thickness in half then dry it some more before resawing.
For building, my wood is at somewhere between 6% and 7%. You might be able to get away with it as high as 10% but I think you might be taking some chances. I use a Wagner pinless moisture meter but it's $200. I only bought the pinless type (which is more expensive) because when you are buying wood from someone and measuring the moisture, they don't take kindly to you poking holes in it. Another nice feature of the more expensive models is in being able to calibrate the meter for different species of wood. It's simple to build a dry box/cabinet, any size you want to dry and store your wood in. I keep a small dehumidifier in mine but the same results can be had with a light bulb and a way of keeping the air moving (convection, small fan, etc.)

Thanks Chuck. Most of the wood I was thinking of resawing has been cut for at least a year and they are around 2.75 inch thick. Looks like Im going to invest in a meter ;)

Moore Bettah Ukuleles
12-21-2010, 07:24 AM
I don't know what kind of wood you're resawing but figure on a minimum of 1" thickness per year for air drying under optimum circumstances.
Moisture meters vary a lot in how they work. The one I have does a poor job in reading surface moisture, but has a target of between 1" and 2" of depth, which is what I'm really interested in. It won't correctly read the moisture of a 1/4" board for instance, but it will read it accurately if you stack up several 1/4" boards. Do your research.
Naturally, if you can afford to do so, buy green wood many years before you plan to use it. Or pay a bit more and buy air dried or kiln dried. Learn how to properly sticker and store and treat the ends of green wood. I've seen lots of green wood twist, warp, crack, damaged by bugs or rot because the the drying was hastened or due to neglect or mis treatment. I recently discovered a large cant of koa that split right down the middle because I had stored it improperly.
Again, I think a dry box is a must.

tattwo
12-21-2010, 09:33 AM
Thanks for all the info Chuck. I wont rush the prosess. I have found some great wood. I guess I will start setting aside for the future

Timbuck
12-21-2010, 10:40 AM
What if it gets wet again? like floods, leaking roof, or soaking before bending ? and using water based stain etc: :confused::confused:

tattwo
12-21-2010, 10:45 AM
What if it gets wet again? like floods, leaking roof, or soaking before bending ? and using water based stain etc: :confused::confused:

I guess let it dry out again?? :confused: ....Thanks Timbuck