Message Thread:
Drying Red OAK 4X6 Green Wood
1/20/20
Hello,
I am trying to dry out some wood just milled 10 days ago. I'm building a rustic bar with green lumber and I have it built in my basement. Do I want to run my pellet stove or not? The bar is 8' from the stove and the room temp. can approach 80*. I have some checking on the wood, but it looks cool with the look of the bar (that's kind of the idea), but I don't want it to split into 48 billion little toothpicks. Any help would be great.
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1/20/20 #2: Drying Red OAK 4X6 Green Wood ...
Website: http://www.tsmfarms.com
Doublewide, as we say here in the country, you've got the cart before the horse....BUT salvagable. There's proper joinery techniques for working green wood which EVERYONE should learn as they apply greatly for both green and dry woods, it's ALL about learning wood movements. Not doing a class here.....soooooooo.... PROVIDING you DON'T anchor a top to this OR learn the proper techniques to anchor for floating, your frame will survive BUT it will shrink in the basement (or anywhere else) and especially with the heat source. Timbers are slow drying due to size. I would run a fan on low NOT blowing on the bar BUT circulating the air around the room and a DHumidifier to remove the moisture...you've sealed most of the wood already, finish ALL bare spots/parts to balance the drying. That will get most of the basics. I do like the layout !!!
1/21/20 #4: Drying Red OAK 4X6 Green Wood ...
Website: finecraftsmanlumber.com
Oak is a very hard specie to dry because it is very prone to checking and splitting. Not only that, oak also shrinks A LOT during drying. Tim hit a couple good points. I would try to keep the drying rate as slow as possible. This means keeping a low temperature and a high humidity. I wouldn't turn on your stove until it gets below 30% MC. I like the idea of running a fan but not directly over it, but would also wait with this until around 30% MC. Running a dehumidifier will help remove moisture and control the humidity of the room. But I would try to keep the relative humidity at 90-95% because oak needs to dry that slow. But I honestly don't think you will be able to achieve this in the basement of a home though. Putting a finish on will also slow down the drying rate. But because the wood cells currently have so much water in them, I don't know how well a finish will stick or absorb into the wood. I would have waited for the wood to be dried to the proper MC before building the project. Drying oak that thick is very, very, very difficult to dry well in a fully controllable kiln. I know some very experienced kiln operators that wouldn't even attempt to dry oak that thick. But you've already made the project so you have to work with what you've got. Good Luck!
Also, I've written blogs and made some videos on Wood and Water Relationships. They might be worth a quick visit:
https://finecraftsmanlumber.com/wood-and-water-relationships-moisture-content-part -1/
https://finecraftsmanlumber.com/wood-and-water-relationships-shrinking-and-swellin g-part-2/
https://finecraftsmanlumber.com/wood-and-water-relationships-wood-movement-part-3/
https://finecraftsmanlumber.com/wood-and-water-relationships-moisture-content-part-1/
1/21/20 #5: Drying Red OAK 4X6 Green Wood ...
Website: http://www.tsmfarms.com
Thanks Jessica, I didn't want to get into all the heavy details as it does get overwhelming for a beginner woodworker much less a seasoned. From all the studies I've read and hands on usage, I find understanding moisture and movement associated with wood AND proper joinery a craftsman can build with either green or kilned without the issues most have due to improper joints/joinery and NOT pre- paring for movement. Using the correct breathable finishes also effect proper slow curing needed for green wood builds. I'm not against Kiln Dried lumber, I'm for understanding both techniques and using them correctly. I also KD lumber BUT this is what I've found out...it also requires proper storage once brought to its specified number...and that starts once it leaves the kiln into storage, to the wholesale, to the retail, in the shop and even the final destination.
With ALL that said, proper joinery and acclimation is a craftsman BEST friend. Again thanks Jessica, I enjoyed the video,GREAT info!!!
1/22/20 #6: Drying Red OAK 4X6 Green Wood ...
You run risks of complete failure of the wood and joinery, to powder post beetles hatching out and spreading inside the house. Green lumber is fine for a bench in a shed, but not furniture in the house.
1/23/20 #7: Drying Red OAK 4X6 Green Wood ...
Website: finecraftsmanlumber.com
Thanks Tim! I agree, you need proper joinery no matter what kind of project you are working on. The lumber will still move even after drying it to the proper MC. It's one of the joys of working with wood! And yes, the lumber needs to be stored in a, somewhat, control environment after it has been dried. Things like you want to keep dried lumber in a building to keep rain or snow and direct sunlight off of it. It is also very important to let the lumber acclimate to the environment of your shop. This will reduce any stress the lumber might have picked up from changes in the environment. It sounds like you have some experience with making pieces out of green timber, and that's not my ball game. I think green lumber can have its place in some projects, but not for anything going in a home. First off, kiln drying removes 95% of wood movement. Green lumber, no matter what specie it is, will shrink a lot and affect the joints, even if you account for all this movement. Boards will still cup and get narrower in width and thickness. Gluing green lumber is also very difficult. This is because the wood cells are so saturated with water, there's no room for the glue to get in. This can result in a weaker bond. It can be done, but it's very difficult. There's a reason why large furniture manufacturing companies use KD lumber, and have for many years. It's because they would be out of business from all they claims they would have on their products. The wood will move and joints won't be as tight as what they were when they were made. The wood might check and possibly split. Most customers want their kitchen cabinets, molding, doors, etc to look the same 10 years down the road. There's nothing you can do to stop wood movement.
1/23/20 #8: Drying Red OAK 4X6 Green Wood ...
The wood won't split into toothpicks but every piece will probably develop large cracks as they dry out just like barn beams do. It's good you want that look. As others have stated slow drying will help but is not practical in your situation. Powder post beetles may emerge if they are present in the wood. They won't spread inside the house as they only re infest high moisture wood. They will most likely not be able to propagate.
1/23/20 #9: Drying Red OAK 4X6 Green Wood ...
Website: http://www.tsmfarms.com
LOL Jennifer, I never mentioned gluing. I mentioned understanding greenwood and proper building techniques. There's LOTS of false info floating around from lack of knowledge and understanding about greenwood. Here's a link to start with http://www.greenwoodworking.com/PeterFollansbeeSleuthing . Pre 1700 there was no/little kilns or glue joints. There are MANY pieces of furniture still in existence from pre kiln era...kilns were created for the industrial large scale manufacturing. All I'm stating is things can be properly built from greenwood with proper knowledge of the wood , it's character and techniques. PS....with kilning in hardwood you remove 95% of moisture not movement...wood is always a living material, green or dry...make moisture changes and it moves.
*note*A "Kiln" is actually the unit/box/building the lumber is "dried" in or moisture is removed from material in.....sterilizing is the 2nd process done in the "kiln" for bug killing/removal aka sterilizing (involves a higher temp than drying most of the time), with soft wood as pine there is a different stage or a even higher temp range for "setting" the sap. All rolled up as one KD BUT actually 2 or 3 different processes.
I couldn't find the hardwood associations definition of Kiln Dried except it was a process used to dry lumber it didn't mention sterilization/debugging.
1/25/20 #10: Drying Red OAK 4X6 Green Wood ...
Until we had dehumidification power for the kilns (the early unit operated with Freon 22 or 12 and did not go over 115 F in the early decades of their use), it was rare that a kiln drying process was ever done completely under 150 F, so "sterilization" and setting the pitch were a part of the schedule automatically.
Prior to the development of the kiln drying method, wood was dried to a low moisture content in the wood shop by storing the wood in the rafters or other heated areas of the shop. Early woodworkers knew about wood shrinkage.
Also, most offices and homes did not have central heating, so the humidity conditions in a home were very close to outside conditions...12% MC...so kiln drying to a lower MC, like 6% MC, was usually not needed.
Did you know that Egyptians were gluing wood over 2000 years ago?
1/25/20 #11: Drying Red OAK 4X6 Green Wood ...
Website: http://www.tsmfarms.com
Thanks Gene!!! Shoot me a link if you have it on the reference to the egyptian gluing....THAT'd be interesting reading. Also thanks for the kiln basic history.
1/25/20 #12: Drying Red OAK 4X6 Green Wood ...
Here's the link:
History of Wood Veneer
1/26/20 #13: Drying Red OAK 4X6 Green Wood ...
Well I'm moving ahead on this project. Everything looks fine. I know log cabins have been built for hundreds of years using green timber. It should crack a bit but still be plenty strong. I put a fan on the project and I run the pellet stove a little bit. I designed the wood joints to have some play, so time will tell what happens. Thanks for all the help. I included some updated pics.
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1/28/20 #14: Drying Red OAK 4X6 Green Wood ...
Website: finecraftsmanlumber.com
Tim, I think some of what I said got slightly misinterpreted. I'm not denying the fact that someone can make furniture out of green or air dried lumber. Your right, the proper precautions need to be in place so that piece can last forever. Like I mentioned previously in this thread, you cannot stop wood movement, even if the lumber is kiln dried. The lumber will still shrink and swell after the piece is complete. I was just trying to state that green lumber, especially anything above 30% MC, will shrink a lot more compared to kiln dried lumber. You can't avoid it, but you do need to compensate for it in the build. I agree, heat treating and setting the pitch or sap are processes that are normally just wrapped up with the term KD, but they do require certain temperatures. But as Gene mentioned, most current kiln schedules encompass these temperatures during the drying process. This is why most people do not view heat treating and setting the pitch a 2 or 3 process, but rather another part of the kiln drying process. As for gluing, I never said it was impossible to glue wet lumber, just that it is more difficult. Thanks Gene for the great read! Hopefully this clears up what I was talking about. Sorry about any confusion.
1/28/20 #15: Drying Red OAK 4X6 Green Wood ...
Hey Doublewide, One last caution. You probably ought to use some sort of foot pads under the legs if that is a real hardwood floor. Otherwise, the moisture in those big legs will be wicking into the floor, and likely ruin the finish under it. If this thing is ever moved, there will be a permanent footprint showing.
1/28/20 #16: Drying Red OAK 4X6 Green Wood ...
Keith,
I have a PVC floor which is waterproof. I put carpet patches glued to the legs using gorilla glue and that allows the bar to slide on the floor nicely. Thanks for the tip.
1/28/20 #17: Drying Red OAK 4X6 Green Wood ...
Website: http://www.tsmfarms.com
Jessica, we're good, no problems. You hit the nail on the head about compensation. That's why I indulge learning (I didn't state have to use it) the greenwood side of building as to it gets deeper knowledge into moisture and wood movements and how to compensate for it....the joinery is the same green or dry except you know what to expect and prepare for. 80% of craft people have NO clue of wood movement, why it moves, how MC and humidity work together or apart, ESPECIALLY about gluing and joinery. Most assume because it's "dry" (KD or AD) there is no movement from that point. I go a little deeper in depth and advise craftsman to learn about their medium (wood) and it's actual properties.
This is NOT to belittle any one...I recommend the same in welding (metalurlagy) I'm 30 plus year welder but when I took a blacksmith class I learned more about the true basics and why things react, stone masons (differ rock has differ porousity and density).
I'm encouraging learn the base knowledge of a medium and the advancements are easier to understand.
BLESSINGS and have a great day!!!
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