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Mostly successful load out of kiln, less one epic fail why?

Started by cabindoc, September 16, 2021, 06:01:01 AM

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cabindoc

pulled a load of red pine out of my Nyle DH kiln, about 800 bf of mostly big cants and some smaller ones.  smaller cants, 4x6, showed around 8-10mc give/take.  Bigger cants, 10x12, around 12-14mc.  Then there was this one that stayed at around 20mc and blew out radial around the pith.  Most of this pine was from the same area, mostly cut recent with sap up.  Other cants that size on pack dryed to the target 12-15mc and look fine.  So, the question is why?

Drying schedule was 120/75 for first week and 1/2, then we notched up as wb creeped up until we got to130/129 which was after about 14 days.  Turned compressor off, set db to 160 and left for 2 days. Probably should have been 3 but...   

1 Defective log?
2 Location in kiln?  Not on bottom row, not on top row, second one up on equipment side
3 Should have left in @ 120/75 longer?

Your thoughts gentlemen?  and ladies if any... 8)

 

 
Scott  aka cabindoc  aka logologist at large
Woodmiser LT35 hyd
Kabota MX5400

Don P

I see a ring shake, likely bacterially infected, look up wetwood in pine. Then study up on whether sap "goes down", that is generally a wives tale.

doc henderson

looks like what has been described to me (never seen it) as bacterial shake.  it was in the tree.  at the end of the cycle, when the DB/WB was nearly one, your humidity was near 100% so not much drying was happening.  I think it could be used as a post.  bacterial infection can hold moisture and shake tends to follow the rings.  you can watch @GeneWengert-WoodDoc webinars on drying on the NHLA website.
Timber king 2000, 277c track loader, PJ 32 foot gooseneck, 1976 F700 state dump truck, JD 850 tractor.  2007 Chevy 3500HD dually, home built log splitter 18 horse 28 gpm with 5 inch cylinder and 32 inch split range with conveyor powered by a 12 volt tarp motor

YellowHammer

The radial failure is due to "shake" or "wind shake" and is a defect in the log.  That's the best thing that could have happened, so you can identify the structural issue and cull the stick.

It's very common is some logs, especially hardwood, and is a death sentence to that piece.  It generally manifests as a fairly small looking defect on the end of the log, when the log is green, but is a catastrophic defect when the wood has been dried.

YellowHammerisms:

Take steps to save steps.

If it won't roll, its not a log; it's still a tree.  Sawmills cut logs, not trees.

Kiln drying wood: When the cookies are burned, they're burned, and you can't fix them.

Sawing is fun for the first couple million boards.

Be smarter than the sawdust

cabindoc

Thanx so much guys.  Whew!  I thought I had a major kiln airflow or something.  Also on the webinars.

Scott  aka cabindoc  aka logologist at large
Woodmiser LT35 hyd
Kabota MX5400

GeneWengert-WoodDoc

Let me add to the excellent description and information.

The bacteria enter through the roots, so the wood they infect will be in the bottom of the butt log.  If you look at the other end of the piece with shake, you should see much better quality, if not perfect.
Gene - Author of articles in Sawmill & Woodlot and books: Drying Hardwood Lumber; VA Tech Solar Kiln; Sawing Edging & Trimming Hardwood Lumber. And more

Larry

I got a load of pin oak to kiln dry years ago from a forum member.  When he showed up I said the lumber had shake and I didn't have to look at it.  Shake smells like rotten eggs.  The green lumber didn't look too bad, so we decided to go ahead and dry it.  After drying the shake was very visible, but I was glad that he got some usable lumber out of it.

Larry, making useful and beautiful things out of the most environmental friendly material on the planet.

We need to insure our customers understand the importance of our craft.

GeneWengert-WoodDoc

In addition to wearing the wood, the bacteria create a fatty acid that turns rancid.  Bacterial infected wood has much higher green MC, so drying is longer.

Some species, especially hemlock, have excessive bacteria and shake in trees much over 75 years old.  As a result, hemlock is not a preferred commercial species. Cottonwood is another.  Willow is another.  Forests that have had cattle grazing, whose hooves damage the roots and let the bacteria in, are especially prone to bacterial damage.  An infected log, due to higher MC from the bacteria, will not float in water but sinks.  Such logs are called sinkers.  They are at the bottom of a lake or stream today still even though they sank a century ago. Shake is common.
Gene - Author of articles in Sawmill & Woodlot and books: Drying Hardwood Lumber; VA Tech Solar Kiln; Sawing Edging & Trimming Hardwood Lumber. And more

Don P

I was reading in Jonathan Carver's travels last night, a few years before Lewis and Clark, and noticed this description;
QuoteThe HEMLOCK TREE grows in every part of America in a greater or lefs degree. It is an ever-green of a very large growth, and has leaves fomewhat like that of the yew; it is however quite ufelefs, and only an incumbrance to the ground, the wood being of a very coarfe grain, and full of wind-shakes or cracks.
When we were building this house a large old oak fell across the drive. I sawed it up and stickered it in the living room for cabinet and trim lumber. It reeked. One of our family stories is our young nephew visited within that week and tugged on my sister "Mommy, it smells like pee in here!" The joys of cat pith oak. I was a bit worried but with a finish the smell has not reappeared. Go carefully there for others, stinky bacterially infected wood has caused furniture recalls.

If I see shake in the butt cut I'll start dropping off chunks of firewood, often I can salvage a good sawlog by getting above the shake.

GeneWengert-WoodDoc

Hemlock was an extremely valuable tree in the eastern forests.  For many years, eastern hemlock trees were cut and then the bark was peeled off.  The bark was valuable for tannic acid that was used for tanning leather.  The wood was left in the forest.  I have seen many pictures of this practice in West Virginia.
Gene - Author of articles in Sawmill & Woodlot and books: Drying Hardwood Lumber; VA Tech Solar Kiln; Sawing Edging & Trimming Hardwood Lumber. And more

Stephen1

Quote from: GeneWengert-WoodDoc on September 17, 2021, 09:30:26 AM
Hemlock was an extremely valuable tree in the eastern forests.  For many years, eastern hemlock trees were cut and then the bark was peeled off.  The bark was valuable for tannic acid that was used for tanning leather.  The wood was left in the forest.  I have seen many pictures of this practice in West Virginia.
Big time up here in Ontario also. Now it is rare to find Hemlock without the shake in it here. The good hemlock comes out of the Government thinnings in Algonquin Park just north of me. 
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