What's the best way to dry this wood?

[Phil Harding]

I recently got a deal on 200 board feet of red oak. The 10 foot pieces range in width from about 8" to over 20" and 1 1/8" to 1 1/4" thick. The wood has been air dried for 10 years (at least that's what the seller claimed). I measured the moisture content at 10%. I currently have the wood stickered and stacked in my shop (heated/air conditioned with a dehumidifier) and the garage. I want to use this wood to make interior doors starting this fall.

My question is what's the best way to dry this wood to around 6% (other wood in my shop is at 6%)? I've found plans for solar kilns on the web and if necessary I could probably cobble something together rather cheaply. Or, should I seek out a local sawer who provides kiln services in the Milwaukee area? Or, is it likely that if I can leave this wood stored indoors it will equilibrate to about 6% in the next two to three months?

Thanks, Phil

[Nate Carey]

...the only way to get from 10% mc to 6% mc is to forcibly remove more water from the wood. Perhaps you can find someone in your area who can do this for you.

Personally, if I was certain that the lumber is 12% mc or less I'd use it as is...

[John Keeton]

I agree with Nate. The oak will do fine at 10%, and probably is close to what it would be once in the home as completed doors. It may get close to 8% in winter, depending on your climate and heating system, but 6% is bone dry, and probably not anywhere near where the oak will end up once in the house.

[Frank Drew]

I agree with Nate and John; particularly after a summer in your air-conditioned shop I wouldn't hesitate to use the wood. Good practice, though, is to approach your final dimensions in stages, just to avoid any unhappy surprises.

[harry strasil]

just think of what 6% wood used as doors in your house is gonna do in the winter when house humidity is supposed to be 35% or a little more.

[Robert Parrish]

6% is great if you live in Arizona! When my wood hits 10-12% I use it. I used to air dry my Red Oak when I lived in Virginia to 8-12%, here in Florida everything is around 10%.

[Lee Schierer]

If your other wood measures 6% and the new wood measures 10% on the same meter then it is not ready for use in your shop. You need to either wait for it to dry in your shop so it reads the same as other wood or get it dried in a kiln (home made or commercial) if you are in a hurry. You mention that you have A/C and a dehumidifier in your shop. They both will reduce atmospheric moisture and allow the wood to dry more, but will require time. (Hopefully you aren't runnig both at teh same time as only one shold be needed.)

The 4% moisture difference will cause you problems in your final assemblies.

[John Keeton]

I agree with Lee IF the two woods are going to used together in the project, but that wasn't how I took the post. Perhaps Phil can clarify that point.

Phil, I have a .pdf file on wood characteristics that I will send you. If you are interested, PM me with your email address. It is exhaustive - and beyond my level of expertise. But, there is some useful info in the article, including several tables.

Generally, at 70 degrees, and a relative humidity of 55%, the wood should reach an equilibium of 10.1%. In order to get to 6% at 70 degrees, the relative humidity would need to be at 30%. For a healthy situation (people and furniture), an indoor relative humidity of 35% - 50% is preferred from my understanding. My sinuses agree!

We keep our home at about 78 degrees in the summer, and a rel. hum. of about 40%. That would give an equil. at about 7.6%. In winter, we keep it at 68 degrees, and the rel. hum. at about 35%, which would give an equil. at about 6.9%. Given those factors, there is little change in the wood from season to season.

Personally, I would prefer to have my doors shrink ever so slightly (from 10% to 7%), than to have them swell. They tend to operate much better that way!

[Phil Harding]

Based upon your comments I won't bother to get this wood into a kiln for further drying. The older red oak that I have had in my shop for more than a year now does measure 6% and the new wood measures 10%. But, since I don't plan to start this project until after the summer season is over I won't worry about the moisture content until then, if at all. It's not likely that I'll be mixing this wood with the older red oak for this project as the colors are too different.

Lee, my shop is in the basement. I run a dehumidifier down there all summer to protect my tools and also to avoid the musty mildewy odor I would otherwise get. The A/C is a central system but I usually close off the outlets in the basement since it doesn't get very hot down there.

Thanks all, Phil

[Curt Harms]

and stick it in the (pretty dry) basement, the moisture content will drop pretty quickly to match other wood of the same species that's been there for months. My basement stored wood will run about 10-11% in the summer and 6% in the winter when the heat's on. We try not to run the A/C if we can stand it with just fans.

[Eric Larsen]

I agree with Nate. The oak will do fine at 10%, and probably is close to what it would be once in the home as completed doors. It may get close to 8% in winter, depending on your climate and heating system, but 6% is bone dry, and probably not anywhere near where the oak will end up once in the house.

Unless, of course, he's building doors for my house. :D

(Although I can't complain, we're at a rare 20% today, probably the last we'll see of double-digit humidity until October.)

[John Keeton]

Eric, I don't how you guys stand that kind of "dry heat." Kind of like the same heat we use to cook Thanksgiving turkey!! Drives my sinuses crazy - but, then so does 98% humidity that we often get in August.

Equilibrium for your wood is probably 3%:D:D