How to dry big White Oak lumber?

[Rob Will]

OK, OK......this is a very thinly disguised WOOD GLOAT:D .

We spent all day wreslting some big WO logs onto a Woodmizer (LT40 Super Hyd). The largest was about 500 bd ft. All of the logs had to be trimmed on the butt end to fit through the mill. Anyway, per your recommendations, I quartersawed everthing possible. Most of the boards ended up at least 10" wide. One set taken through the center measures 25" wide. Another set measures 27" wide. All of these are sawn 5/4.

We also took a couple of 4 x 8 cuts for possible table legs etc. The logs were end sealed before cutting into lumber. All of this will be stickered and stacked tomorrow in a dry metal shed.

Any suggestions on how best to dry this WO?
Any special considerations for the thick pieces?
Should I go ahead and rip the 25" and 27" boards down the middle?
(some of the 27's are going to split anyway)
Would you put a fan in the shed to circulate some air?
If so, for how long?

These particular logs are a once in a lifetime opportunity for me and I want to dry this lumber right. As they came off the mill they were very clear and stress-free.

Thanks for your suggestions,
Rob

[Pete Brown]

Thinly disguised ... suuure! :rolleyes:

That is some gorgeous wood.

I'm sure others with more experience with wet wood will chime in, but you will want to sticker and weigh down (cement blocks should do) all that wood. use lots and lots of stickers and plenty of weight.

The really thick stock is going to take forever (multiple years) to dry. You may find that thick beam to be an issue.

If the 27" wide stuff is going to split cleanly on the pith, then I would think you could just leave it as-is. If it is a large end-check or something that is just going to get worse, I would cut it off and/or rip the board to relieve the stress.

Beautiful wood and nice gloat :)

Pete

[thomas prevost]

fan- definite to draw moisture out. I would even leave the doors open. Otherwise shed will fill with moisture and wood will not dry. You want to move air between the boards. 1yr per inch thinkeness. But I would finish in a kiln after 5-6 months. White oak tends to move a lot if not kiln dried. Sticker every 2 ft and be sure each sticker is exactly above the lower one!!!! lotsa weight on the top to keep the last two rows from cupping and twisting. cut out pith in center cut boards or They will check terrible.

BTY, very nice looking QS oak!!

[Tony Scolaro]

I have milled up lumber several times but that doesn't make me a pro. A few comments. Seal the ends with sealer made for the purpose. Old paint is OK for softwoods, perhaps, but I was strongly adviced against it. I tried parafin melting it in a double boiler but in the heat of the Summer it melted off and it was out of the sun and properly covered. Keep all metal away from it or you will get stain from reacting with tannin acid. Also the stickers should be dry and not milled cut offs. The more weight on top of your pile the better. Also air circulation is a must. In the end you will have some loss but probably lots of good lumber full of character that will match up board for board real nice. And you won't get case hardening and honey combing if you air dry it. Good Luck Tony

[Tom Sontag]

I will part ways with Thomas' suggestions a bit. I have not had much movement with white oak, especially white oak that is QS. QS wood wants to warp flat - it is the edges that curve - also known as crook. This is one reason some prefer to leave quartersawn lumber with the pith intact; it keeps the boards on each side balanced and uncrooked, though of course you will waste the center pith area after it is dry.

Oak likes to dry slowly. I would avoid the fan idea unless you see any blue stain showing up early (not likely this time of year). Dry stickers are critical. Once air dry, then kiln drying to remove that last bit of bound water is required.

[wayne ateser]

usually just load it up in the cart and give em your credit card works pretty well

[Pete Brown]

For drying the maple for my cabinets (it was re-wet from being in a shed for a long time), I used I-beam shaped composite stickers I bought from Grizzly. They worked really well, and no stain issues.

They were expensive, but not as expensive as screwing up all that lumber would have been.

I can't find them on Grizzly any more. Google for durastick (http://www.google.com/search?q=durastick) to see what I'm talking about.

Here's some information (http://www.woodweb.com/knowledge_base/Stickers_and_sticker_shadow.html) on sticker stain.

Pete

[Rob Will]

usually just load it up in the cart and give em your credit card works pretty well

What? I went out and bought a Stihl 660 w/ a 36" bar, a Wood Mizer and a John Deere log skidder to get these wonderful boards. I cant back out now because a local welding shop is building me a dehumidification kiln out of stainless steel. Also had to buy a fork lift to handle these big logs but it looks like we may find other uses for that. Owning a fork lift is great fun but now I'm going to have to pave the driveway because the darn thing is so heavy.

[Homer Faucett]

Everything you wanted to know about drying lumber:

http://www.fpl.fs.fed.us/documnts/usda/ah528.pdf .

Nice score. I love white oak, and find it to be a good candidate for air drying, as others have noted. You could build a small solar kiln to bring it down to 6% after giving it a year to season.

[Pete Bradley]

My first reaction was you should split it for the fireplace next year. I found white oak to be pretty challenging to dry. Your boards are awesome though. I'll second the comments about good end sealing and going slow.

Pete

[Rob Will]

Everything you wanted to know about drying lumber:

http://www.fpl.fs.fed.us/documnts/usda/ah528.pdf .

.

Wow! now that 110 page document will keep me out of trouble for a couple of hours.
Thanks Homer.
Rob

[Joe Chritz]

Best way to dry it would be to pack up 200 BF +/- and send it here.

I will take it up the road to the Kiln guy and then use it for an office library and entertainment center.

Nice looking stuff for sure.

The lumber place close to here (he has a large kiln and makes trim) is only about $0.25 per BF to dry.

I don't have first hand knowledge buy I have heard a year per inch minimum for using air dried lumber.

Good Haul

Joe

[Kevin Scott]

I am not sure about drying the wood... but man, am I envious!!!!! QSWO is one of my favorite woods. Great score.

[Scott Banbury]

Like Tom said, dry it slow at first. Even though you might not see them, drying too fast off the start will result in surface checking and or case hardening--especially on thicker material.

Those wide cuts through the middle of the log will split along the pith. You also risk them being wavy as the pith wood has a lot of variation in density and pulls the surrounding heartwood this way and that as it drys.

Quartersawn boards will always crook to some extent.

My page on quartersawing:
http://www.scottbanbury.com/quartersawing.html

[Dan Drager]

While my pile isn't as impressive. I am air drying my Oak and Hickory in an outside stickered stack for approx 2 years to bring the moisture content down to around 15%, the lowest you'll get by air drying around here. Then it will go to a local Kiln for finishing the drying to about 5-8%. This was recommended to me by multiple sawyers in the WI area. Good luck and be patient.

[Rob Russell]

If you didn't do it before you sawed up the log, coat the ends of the boards with Anchorseal. That's a waxy paint that will seal the ends of the boards and help prevent cracking.

After the Anchorseal is dry, write on the end of each board something to identify it - WO-1/4 or WO - FS for White Oak, quartersawn or flatsawn. That way when the boards are stacked with other wood, you can see what's in your pile.

Make sure that you sticker the lumber - I did every 16" with my stuff.

[lou sansone]

OK, OK......this is a very thinly disguised WOOD GLOAT:D .

We spent all day wreslting some big WO logs onto a Woodmizer (LT40 Super Hyd). The largest was about 500 bd ft. All of the logs had to be trimmed on the butt end to fit through the mill. Anyway, per your recommendations, I quartersawed everthing possible. Most of the boards ended up at least 10" wide. One set taken through the center measures 25" wide. Another set measures 27" wide. All of these are sawn 5/4.

We also took a couple of 4 x 8 cuts for possible table legs etc. The logs were end sealed before cutting into lumber. All of this will be stickered and stacked tomorrow in a dry metal shed.

Any suggestions on how best to dry this WO?
Any special considerations for the thick pieces?
Should I go ahead and rip the 25" and 27" boards down the middle?
(some of the 27's are going to split anyway)
Would you put a fan in the shed to circulate some air?
If so, for how long?

These particular logs are a once in a lifetime opportunity for me and I want to dry this lumber right. As they came off the mill they were very clear and stress-free.

Thanks for your suggestions,
Rob

hi rob
the best advise can be had over at woodweb's sawing and drying forum. my 2 cents from my own experience with my mill is the following

oak can be hard to dry. most everything I have read about it says that, and my experience also bears that out. If I had a kiln, that would be one of the species I would dry with a kiln. without the kiln, you do want to get the moisture out quickly rather than real slow ( although there does seem to be a difference of opinion here about that ) . a fan to move air around and through the pile will help. I would not direct it directly at the pile.

I am not a quarter sawing expert, but the comment about leaving the heart in to balance the board's stresses new to me. My experience has been that every board that is sawn that way will blow apart at the pith and take with it a lot more wood than would be lost by simply cutting the heart out of it. After many bad experiences with leaving the pith in my lumber, I now always make a practice of removing the pith. But maybe the supposed crook you get is worse than the pith section damage. again, I would yield to the experts at woodweb.

you can label your boards, but after a few thousand feet, I find it useless to do and I just pile it in there and pull it out and look at it when I want. But Louis irion loves to label his lumber and so do some other. I have done it and don't do it any more.

I agree with rob in the 16" spacing. Use dry stickers to be safe, or you will risk sticker stain.

beautiful wood indeed
best wishes
Lou

[Tom Sontag]

Let me clarify two things:

1 - the idea of leaving the pith in a wide qs board to balance stresses and avoid some crook is not one I always use. But given the amount of crook that I have had on some boards, I think it could save more wood than it costs from pith checking. I have had it work for me. Sure you lose 3 or 4 inches at the center; you would have cut most of it away when green anyhow. If a 10' board crooks 5 inches, maybe it makes sense? Not required, certainly. Just an idea. This might be more important on a board with sapwood included that shrinks excessively (like cherry).

2 - Oak, especially white oak, simply must be dried slowly. You can do this in a kiln no doubt, but for the same reason it makes good whiskey barrel material, you cannot rush it. Water migrates through the cells very slowly. If you blow too much air across the surface on day one, you will get surface checks that only grow over time. I had this happen just sawing WO on a sunny and windy day. The surface dries and shrinks while lots of water is still swelling the cells just a quarter inch further in. This gives you surface checks and is one of the drying defects that WO is subject to. Like case hardening and honeycombing, the problem is an improper rate, usually too fast. The only downside of too little air flow is blue stain or sticker stain and this I've not had in a proper stack. Don't wrap the pile in plastic, but don't put it in a wind tunnel either.

I read woodweb extensively before embarking on making a number of mistakes myself; surely there are more knowledgable and experienced dryers out there, but I've done my share.

[lou sansone]

my perspective on drying oak is from experience of sawing plenty of oaks and trying to air dry them. here is just one example that will highlight the fact.

Loss in air-dried lumber

The Wood Doctor provides typicial loss factors for several speices of lumber, when air-dried. 1998.


by Professor Gene Wengert
Q.
What is the rule of thumb for wastage in oak lumber air dried as a percentage of total sawn?
A.
I believe your question is "How much loss is there in air drying?" This question was examined some years ago by the US Forest Service. They looked at a variety of grades and species dried in Pennsylvania. These drying degrade losses presented here for No.1 Common grade do not consider any value losses due to ordinary shrinkage. Drying losses were higher for FAS lumber and lower for No.2 and No.3 Common.
It's important to note that the data was collected by grading the lumber before drying and then again after drying. As almost all grade losses occur during air drying, not subsequent kiln drying, this technique is very good. However, it does tend to underestimate the loss to a furniture or cabinet plant that is cutting the lumber--grades do not reflect the loss in yield very well. So, I would double the losses for them.
For lumber that was No.1 Common when freshly sawn, the loss after air drying amounted to a value loss of: Basswood - 8%
Birch - 6%
Hard Maple - 14%
Red oak - 13%
White oak - 15%

or just read this pub
http://www.fpl.fs.fed.us/documnts/fplgtr/fplgtr118.pdf

oaks are considered "hard to dry" species

lou

[Rob Will]

Like Tom said, dry it slow at first. Even though you might not see them, drying too fast off the start will result in surface checking and or case hardening--especially on thicker material.

Those wide cuts through the middle of the log will split along the pith. You also risk them being wavy as the pith wood has a lot of variation in density and pulls the surrounding heartwood this way and that as it drys.

Quartersawn boards will always crook to some extent.

My page on quartersawing:
http://www.scottbanbury.com/quartersawing.html

Scott,
Everybody around here thinks I'm nuts for hunting big logs. Never mind the fact that we have some big machinery to handle them with.....I'm always getting a hard time about it.

I'm printing out a few pages from your website to lay on the office desk tomorrow. I bet I'll never hear another comment about "big" logs.;)
Great technique.

Thanks,
Rob

[Homer Faucett]

Lou,

I'm a little confused by your posts. How would kiln drying oak (a faster, and more stress-inducing method) reduce checking and wood loss as opposed to air drying?

Further, your follow-up post simply compares the wood loss among several different types of wood when air dried. All that says is that white oak tends to have more wood loss than birch or basswood as it dries.

There is no comparison of the loss of air dried wood to wood that is instantly kiln dried from green lumber. That is the type of comparison that would need to be given to make a determination that the wood should be instantly kiln dried instead of air dried. Further, the comparisons do not take into account the differences in loss when the wood is quarter sawn (as the original poster's boards are) as opposed to flat sawn.

I guess I'm just trying to figure out exactly whether I am understanding what you are getting at. It sounds like the moral of the numbers you give says that you can just pretty much expect about 10-15% waste from a log due to drying wood. Based on those numbers, white oak doesn't seem statistically any more tricky to dry than red oak or hard maple.

[Rob Will]

Thanks for the help.
Here's two more pics of this White Oak.
Some of it has an interesting pink tint but it is definitely WO.
Do I need to cut the heart out of this board or just go slow and wait to see what happens?

Rob

The reddish cast shown here is moisture, not heartwood/sapwood

[lou sansone]

Lou,

I'm a little confused by your posts. How would kiln drying oak (a faster, and more stress-inducing method) reduce checking and wood loss as opposed to air drying?

Further, your follow-up post simply compares the wood loss among several different types of wood when air dried. All that says is that white oak tends to have more wood loss than birch or basswood as it dries.

There is no comparison of the loss of air dried wood to wood that is instantly kiln dried from green lumber. That is the type of comparison that would need to be given to make a determination that the wood should be instantly kiln dried instead of air dried. Further, the comparisons do not take into account the differences in loss when the wood is quarter sawn (as the original poster's boards are) as opposed to flat sawn.

I guess I'm just trying to figure out exactly whether I am understanding what you are getting at. It sounds like the moral of the numbers you give says that you can just pretty much expect about 10-15% waste from a log due to drying wood. Based on those numbers, white oak doesn't seem statistically any more tricky to dry than red oak or hard maple.

Hi homer
good questions. With a kiln, you can control the rate of water loss, and it is often monitored by kiln operators. With air drying it is more difficult, because you are not controlling the environment as you are with a kiln. There are forced fan drying sheds that can speed up the air drying process, but it is not the same as a kiln, where you can control the temperature and humidity. you are right the oak and maples are prone to pretty big losses during air drying, but as the article says, there is no subsequent loss during the kiln drying process. If you read through the pub I hyperlinked you will see more detail on this. I was surprised about air drying oaks when I first ran across this information, but it confirmed what I had experienced myself by trying to air dry oaks. Another almost impossible to air dry species is beech. I have lost close to 1000 bd feet trying to air dry it.
I toyed with buying my own kiln, but have not yet. Rob's lumber is beautiful, but I work mainly in the 18th century American style. I would like to do a couple of 17th century pieces which would require oak. At this time I only stock much easier to air dry species, such as butternut, walnut, cherry, poplar , and soft curly maple. The quality of Rob's wood is such, that I would find a good kiln operator and have it all kiln dried.

Lou

[Rob Will]

Hi homer
good questions. With a kiln, you can control the rate of water loss, and it is often monitored by kiln operators. With air drying it is more difficult, because you are not controlling the environment as you are with a kiln. There are forced fan drying sheds that can speed up the air drying process, but it is not the same as a kiln, where you can control the temperature and humidity. you are right the oak and maples are prone to pretty big losses during air drying, but as the article says, there is no subsequent loss during the kiln drying process. If you read through the pub I hyperlinked you will see more detail on this. I was surprised about air drying oaks when I first ran across this information, but it confirmed what I had experienced myself by trying to air dry oaks. Another almost impossible to air dry species is beech. I have lost close to 1000 bd feet trying to air dry it.
I toyed with buying my own kiln, but have not yet. Rob's lumber is beautiful, but I work mainly in the 18th century American style. I would like to do a couple of 17th century pieces which would require oak. At this time I only stock much easier to air dry species, such as butternut, walnut, cherry, poplar , and soft curly maple. The quality of Rob's wood is such, that I would find a good kiln operator and have it all kiln dried.

Lou

Lou,
What do you consider the biggest risk in air drying big white oak? End checking?
Rob

[Homer Faucett]

Hi homer
good questions. With a kiln, you can control the rate of water loss, and it is often monitored by kiln operators. With air drying it is more difficult, because you are not controlling the environment as you are with a kiln.

That makes good sense, but let's remember that the whole purpose of the kiln is still to accelerate the drying, or increase the speed of the water loss. I cannot imagine a kiln that is made to have a higher relative humidity than the ambient air--at least not in the Midwest here. Maybe in Arizona that would be true.


There are forced fan drying sheds that can speed up the air drying process, but it is not the same as a kiln, where you can control the temperature and humidity.

I have not used these, so I can't speak to them, but I can see where using fans improperly could impart uneven stresses to a board. Most kilns are still going to have a fan and some way to reduce relative humidity (usually by raising the temperature) to increase the speed of drying.


you are right the oak and maples are prone to pretty big losses during air drying, but as the article says, there is no subsequent loss during the kiln drying process. If you read through the pub I hyperlinked you will see more detail on this.

I think you make an important point here, but the reasons can be easily explained. First, note that all the wood here had already been dried from it's green state at 20%+++ water to about 10% water by being air dried. This is where most of the checking is going to occur, because that is when most of the shrinkage and water loss occurs.

The subsequent kiln drying is unlikely to do much more to increase checking (as noted) because (1) most of the shrinkage of the wood has already occurred and there has been an equillibrium established between the surface and the core, and (2) the wood has already split along the most stress-induced areas. This does not indicate that immediately kiln drying would have reduced the amount of checking that ultimately occurred--although I will agree that controlling the environment will reduce checking.

There are some ways to reduce checking, and they are covered in the publication you mentioned, as well as the summary here: http://www.wvu.edu/~agexten/forestry/wooddr2.pdf . The key is to slowly dry the wood during the early stages. Another trick I have been told is (if you can) to cut the tree in the late fall or early winter, when the xylem and phloem in the trunk is not chock full of the water and nutrients being sent back and forth from the roots to the leaves.

Thanks for the tips, Lou!

[lou sansone]

Lou,
What do you consider the biggest risk in air drying big white oak? End checking?
Rob

Hi rob
I don't have enough time to respond in great detail, but in general you could get surface checking of the wood or case hardening if you remove the water too fast from the surface ( putting the pile in direct sunlight would be an extreme example). I will try to point you toward some good articles in FWW that give a nice explanation of how a kiln differs from just random air drying techniques.

IRT the degrade of 15% due to air drying, the whole import of the article was that air drying degrades lumber more than does proper kiln drying. The author is trying to say " listen you can air dry if you want, but you are risking looking 15% because of it, those are the statistics". I love air dried lumber and most of mine is, but not oak, and certainly not beech.

more to follow

lou