Knowledge You Can Build On — Est. 1998
Ideal Moisture Level
Dan Faux
>Hi
I am now at the stage that my home made Vacuum Kiln is drying wood nicely and I am now asking what is the Ideal moisture level. Common sense tells me that 0% is best but is this possible ? I think not.I can get the wood down to about 15% and then when removed it starts to creep up a little to settle at about 17.5%. I live in Western Australia and it is not a very humid place. Any opinions appreciated.
DanF
Re: Ideal Moisture Level
JL work
>The moisture levels in wood vary with the season and relative humidity. In a dry climate (depending on the wood), I would expect values of 10-15% for dried wood.
Re: Ideal Moisture Level
Barry Irby
>Wood generally approaches 20% of the Relative Humidity of the surrounding air. That is Moisture Content equals approximately one fifth of the Relative Humidity of the surrounding air. This is somewhat crude and varies from speicies to species and a little depending on which part of the spectrum you are in. I think most furniture wood is dried to about 6 to 8% and then allowed to equillabrate to the surroundings. Oddly, this relationship is largely independant of temperature. 0% would be undesirable and probably almost never occurs in nature.
Barry Irby
Re: Ideal Moisture Level
Mark Mandell - Gone Round In Jersey
>Average EMC (Equilibrium Moisture Content) for interior wood here in US is about 10-11% - Desert Southwest & West will go to 7%, humid East Coast 12%. 15% sounds high, especially for a dry area as you describe. 0% ("oven dry") is easily possible but cannot be maintained as the wood will soak up moisture from the air until it reaches EMC for your area. The idea is to dry your wood until it gets to your own local's EMC. I'd try taking it to 10% and see how it reacts.
Good Luck!
M
Re: Ideal Moisture Level
Bart Rhoads
>One way to find out is to check a piece of wood that is laying around your show that is out in the open and has been there for awhile. This will give you a pretty close idea of what the MC should be in your area. This will vary with the changing of the seasons and weather.
Re: Ideal Moisture Level *LINK*
Larry
>This site covers everything you ever wanted to know about drying hardwood. It doesen't cover the esoteric methods (alcohol, LDD, etc.) but it does an excellent job with the more commercial/semi-commercial methods (kiln, air, shed, solar kiln). Be advised that the site brings up a PDF file so if you don't have Acrobat it won't work.
Drying Hardwoods
