What You Find Inside Your Wood...

Art Mulder

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London, Ontario
(and I don't mean things like bullets)

I expect to find knots and wild grain inside my lumber. I also expect to sometimes find interesting things -- I haven't found a bullet, but I have encountered nails. I expect to find mineral streaks also. However, I also usually expect to find, well, wood inside my wood! Of course I know that wood isn't a manufactured product, and as a natural growing substance, I should expect to be surprised every now and then.
Like on my current project.

A year or more ago I scored some really nice red oak for a good price. I've used it a few times and always been quite pleased with it. I pulled some more of it inside from the garage a few weeks back for another project, and started dimensioning it.

It's another lovely pile of oak!
oak-lumber.jpg

However, when I started planing it, some of the boards started showing some cracks inside.
oak-cracks.jpg

Hmm, Well I was planning to rip them narrower anyway (making rails + stiles for doors) so I went over to the bandsaw and sliced open a couple of them that had these cracks. Look what I found inside. :(
oak-inside1.jpg
oak-inside2.jpg

Those are some big cavities opening up in a few of those boards!

Most of the wood is fine, but some of it is going to force me to be careful and creative as I cut it up further to the finished size!

And a few of those boards are really bad, like this one.
oak-lots-of-cracks.jpg

Oh, can't see them all in my photo? Here, I coloured most of them:
oak-lots-of-cracks-coloured.jpg

Yup, wood is interesting stuff.
 
That looks a lot like critter damage to me... like something very little got inside & started eating, forming a little village. If it was just case hardening (from too-fast drying), the cracks would appear to be "closeable", but there are distinct hollow cavities in there. Are there any pinhole-sized openings on the outside of the barely planed wood? Little piles of sawdust around the woodpile? Anything that looks like you may have powderpost beetles or some other wood-eating critter?
 
it doesnt appear to be from critters to me art i tend to think its from eith lighting or wind stress..they claim if you drop a tree wrong when cutting it that it can have cracks in it as well but yours shows weathering so must have been there from the time it was cut to dry. the powderpost chewing i have seen doesnt look like that and the big boys eat larger holes..pencil sized comapared to pencil lead sized.
 
That is caused by someone that does not know how to run a kiln and was dried way to fast.
I used to get some of that when I first started in business and it didn't take me long to figure out which company's to buy lumber from and who to run run run from :rolleyes:

Its called honeycombing

Jay
 
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That is caused by someone that does not know how to run a kiln and was dried way to fast.I used to get some of that when I first started in business and it didn't take me long to figure out which company's to buy lumber from and who to run run run from :rolleyes:Its called honeycombing Jay

Though I don't know anything at all about kiln drying wood - this was my first impression.* Drying went wrong.

I also, have had Red Oak that had similar defects inside of it.

I wonder if it is particular to Red Oak?
 
Oh I knew it wasn't critters. I figured it was case hardening, or some such.

I bought this from another woodworker... I honestly don't remember even it had been air dried or kiln dried. Hmmm.
 
I dunno - I've seen checking, even SEVERE checking, from drying too fast... but those photos show pockets of missing wood surrounded by intact wood. If it was just severe checking from case-hardening, wouldn't it look like all the wood was still there - just split apart inside? Those photos are of VOIDS.
 
Its not case hardening Tim its called honeycombing and yes that is what it looks like and yes its caused by to high of heat in the kiln to fast.
Case Hardening is caused by drying the out side to fast at a lower heat and yes it will cause some cracking but not the Honeycombing that to high a heat will cause. Think of it as a steam boiler blowing up inside the wood and leaving voids.
 
Jay got it right in my understanding. Honeycombing is caused by drying the wood too fast at too high a temp or drying it right from the mill without air drying it some. If you pull too much moisture out of the wood quick the fibers don't have time to stress relieve. It can also be caused by drying wood too thick. Oak can't be dried in a conventional dehumidification kiln if it's much more than 3" thick. It can be dried in a vacuum kiln in thicker pieces but I understand that the wood doesn't have the same look and machine the same as conventional kiln dried. At least this is what I understand talking to kiln operators.
 
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