Kiln drying White Oak

Mike_Doolittle · June 12, 2004, 11:49:10 PM

Well I took my first load of white oak out of my DH kiln and it looks like I have more to learn. I didn't get any end checking at all...zero. What I did get was many boards that do not want to lay flat. Anyplace that the grain was not strait, it tended to want to wave. Is there a way around this? Does the kiln temp have anything to do with it? It took me almost 6 weeks from green so I don't think that I went too fast. I want to make some flooring but I feel that I need to true up all of the boards before I dare groove it. Has anybody taken boards right out of the kiln and make T &G in one pass? I need to learn the tricks with white oak and would greatly invite your input.
Mike

Frank_Pender · June 13, 2004, 07:49:02 AM

Mike there is so much tension in the areas of the knots taht you will have to make some short boards for flooring. One of the ways I have kept the load straight is to put large pieces of cement on the load as it is air drying. Even then, I may have some problems with some boards after they have been in the kiln. My friends in Sheridan build some special weights for cement that cover the whole load while air drying and kiln drying.

Mike_Doolittle · June 13, 2004, 05:38:40 PM

Thanks Frank for the info! I was stickered every 16" and much of the warping took place between the stickers. I would be interested in learning more about the weights you were talking about.Mike

Den Socling · June 13, 2004, 05:46:51 PM

It's claimed that you need 300-500 lbs per square foot.

Don_Lewis · June 14, 2004, 05:27:03 AM

Most of the publications about weight say 100 PSF. One way to tell if weight will help is to compare the board near the bottom of the stack with the ones near the top. 12" sticker spacing is better for West Coast grown Oak. Over drying will also cause some of these problem and is a common problem, especially with the first loads people dry. Pay attention to how the boards deformed. Study the grain pattern and relate that to shrinkage tables. You will often see how a change in sawing will improve things. That will make you a better sawyer or better buyer of green lumber.

Den Socling · June 14, 2004, 05:47:18 AM

Don,

100 lbs per square foot may be enough. In fact, the DKOM says to use 50+ lbs. Gene Wengert recommends 300 lbs. And a friend who dries Holly uses 500 lbs.

Den

Mike_Doolittle · June 14, 2004, 07:55:14 AM

Don,
I did talk to you friday and I did over dry this load! I don't think that this was the only problem though because the bottom of the stack is much better and I was seeing the problem develop before the load was dry. I think that I have learned the following.
1. Dont let the temp get up to 145 deg.
2. Sticker the load every 12" instead of every 16"
3. I need some weight on top.
4. grain pattern is a factor.

As far as sawing, I did notice that where limbs were coming out and the crotch area's the problem was much worse. The thing is, this is where the pretty grain is and I would like to be able to save it. Sawyers...how do I saw this in a way that it helps.
On the weight side of things, i'm very interested in what to use. Right now I'm needing to hand load in that I haven't been able to take the time to build a cart and even 100 LB per ft is a lot to pack in and put on the top of a stack. Anybody have suggestions?

The input so far has been super and I hope that others are learning some also!
Thanks much...Mike