I’m making some raised panel door panels using quarter-sawn white oak. The wood has a few isolated areas where the top layer of wood seems to be “flaking off”.
1. Does anyone know what this condition is?
2. Is it caused by some faulty milling technique on my part?
3. Did I buy deffect wood-if so, is it a recognizable, or preventable condition?
4. Is there a way to patch it and make it look acceptable so I don’t have to start the panels over? ( I’m pretty much at the minimum width for my raised panel door router bit set)
Replies
K W
I checked my "Understanding Wood" by Hoadley an I think I know, but do no feel positive enough to answer. I highly suggest you cruise over to the Cafe an find a post from either Jon Arno or Neimechek (sp. Stanley). They are the risident Wood-mo-tologist as both have degrees an have worked in that field. Click on reply to one of their post an ask them to come over an take a look at your thread. At the bottom, instead of clicking post to all, click on e-mail box and then send.
BTW, if you do e-mail to Jon an your a liberal, don't mention it. Vise-versa with Stanley if you happen to be a conservative. ha..ha..
Regards...
sarge..jt
>>" highly suggest you cruise over to the Cafe an find a post from either Jon Arno or Neimechek (sp. Stanley). They are the risident Wood-mo-tologist as both have degrees an have worked in that field. Click on reply to one of their post an ask them to come over an take a look at your thread."<<
Sarge, I didn't waste my time getting a degree in this field...although I think Stanley did. Anyway:
The photos are awfully hard to read, but I suspect what they show is separation between the vertical, vascular tissue and the ray tissue. Because the fiber directions at the point where these tissues meet are perpendicular, the natural bond experiences higher shrinkage stress...The ray cells are oriented longitudinally and virtually don't want to shrink at all, while the vertical tissue is bonded to the ray along its radial plane...which, in white oak, experiences an average shrinkage, green to ovendry, of about 5.6%.
So, the bond along the rays is weak to begin with, and it is one reason why quartersawn oak tends to be a little chippy when planed...and also why, when splitting oak firewood, it tends to pop along the rays. There is some probability that the wood might not have been kiln dried as carefully as it should have been...or perhaps this problem simply reflects even earlier wind damage while the tree was still standing. In any event, it's a risk you pretty much have to learn to live with when working with ray dominant species. As for a cure, the only ones I can think of are to either attempt to glue the lifed rays down or resurface (plane) the stock again to remove them.
Maybe Stanley can shed a little more light, or offer other solutions, but I haven't seen him posting much lately. He may have gone for a walk without his compass. :O)
Jon
Sorry for the mistake on the degree. I thought you did have it. I think Stanley actually does, an yes he's been quite lately. Hopefully busy.
I suspected the improper kiln-drying. The wind-check theory escaped me, but that is possible also. Hickory gets real testy like that at times also. You don't find out till you cut into it.
Again, thanks and have a great evening...
sarge..jt
>>" Sorry for the mistake on the degree. I thought you did have it."<<
No, I've probably read most of the major texts on wood tech, have them in my library and often use them for reference (botany and forestry texts also)...but my degrees are in Bus Ad. I did grow up in the lumber business and have been involved in it off and on most of my life. I just happen to love the subject of wood from many perspectives.
---
>>"I think Stanley actually does, an yes he's been quiet lately. Hopefully busy."<<
Yes, he's mentioned that he's a Penn State grad in this field. And from what I've seen, he's exceptionally knowledgeable on the chemistry and molecular structure of wood. This question about tissue bonding and why vascular cells shrink disproportionately ought to be right in his wheelhouse and I hope he finds the thread.
...But he's probably off on some other tangent. You know these Liberals...somtimes when they find a problem they really like, they can't think about anything else for weeks on end...especially if it involves the solution. (if you're out there lurking Stanley, I'm just kidding, of course. Would like to hear your take on why the ray bond is so weak) :O)
Sarge,
Are you aware that your 'd' key sticks sometimes, especially when you write 'and'? It doesn't do it all the time: sometimes when you write 'and' the 'd' does appear. I know this is a problem with your computer because the 'd' didn't begin to disappear until quite recently, and because you're obviously too intelligent and too literate to adopt such an affectation.
Alan
p.s. you might want to check your 't' key as well.
OK, Sarge, time to give up those home-baked cookies while at the keyboard! After you've turned off the computer tonight, spin the keyboard upside-downside and rap it against your desk a few times. Get them crumbs out, and send me the rest of the cookies!! ROFL!!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)
FG
Took your suggestion and I hit it several times with a dead-blow hammer. Trick I use on my teen-ager to get him to work. Also sent the cookies off to the FBI crime lab to be analyzed. You just never know. ha..ha..
Have a good evening...
sarge..jt
Alan
Thanks for the tip off. Will relay to the chief of computer operations and she will clean the key-board. I have to sneak the coffee in when she's occupied. ha..ha..
Regards...
sarge..jt
K of W,
I'm working on an A&C piece with white oak....and 6" aprons. One of those aprons has a flake about the size of a half dollar (showing my age) so I'll be curious to hear the answer also....
I'm sure you'll get a more qualified answer but it could be internal checks if it is klin dried wood.
Philip
I agree with wop... it looks like a "check" to me. It's not defective wood per se. It's virtually impossible to know if a given piece of wood has internal checks in it until you cut thru one. The cause, as I understand it, is stresses inherent in the process of drying green wood. Although, I've heard them referred to as "wind checks" before... implying that they're the result of stresses incurred before the wood was harvested. Either way, they're a result of stresses to the wood fibers and are just part of the game. Improperly dried wood will have more checks. But... since drying green wood is as much art as science, predicting which source will have more checks than another is virtually impossible.
As for repairing it... there are a number of variations on the same theme: glue and clamp it. Much depends on how wide it is and where it's located at on the piece you're working with. Just about any type of glue will work. Some leave a more obvious repair than others, though. If it's pretty minor and moves easily with just finger pressure, I like to use a wood-rated Super Glue and a block of wood or something like that, with a strip of masking tape on it to prevent it from becoming glued to the wood surface, to press down on it until the super glue sets up. If the check doesn't move very easily with just finger pressure, I like to use yellow glue and clamp it for an hour or so until the glue sets up. Although, Roo Glue or white glue or whatever you prefer (epoxy...) will work the same way. I would avoid the poly glues that bubble up, though. You want to minimize the extent to which the repair glue fills, and thus obscures, the surrounding wood pores. Otherwise the repair will remain pretty obvious. That's the main reason that I prefer using Super Glue when I can.
Regards,
Kevin
Thanks to all for the great responses. I was able to repair the flakes, and can't see the repairs!!!
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