I think a learned something today:
Tried to rip a piece of green pine that was cut from near the center of the
trunk...part sap wood, part heart wood. About 1/5 of the way thru the
piece, the kerf closed up so tightly it bound on the splitter and I couldn't
move the board either fore or aft. I finally drove a narrow wedge into the
kerf to free it up.
Perhaps foolishly, I decided to try to rip it all the way thru. About 80
percent of the way, the forces on the sap wood caused it to split from the
remainder of the board with a loud crack. When I picked up the sap wood,
there was a bow in it that deviated about 1-1/2 inches from straight. BTW,
the heart wood stayed relatively straight.
Lesson duly noted...I shoulda scrapped the piece and not tried to finish the
cut. I'm sure glad that sucker didn't kick back on me.
It is extremely common for pine to have reaction wood near the pith. If you
own Hoadley, believe he refers to this as "Juvenile" wood. This may be what
he's referring to.
If plantation pines are not harvested by clear-cutting, a lot of the
remainder develop wind shakes, because they're no longer collectively
blocking the wind.
"Andy Dingley" <[email protected]> wrote in message
news:[email protected]...
> On Fri, 3 Dec 2004 22:19:38 -0600, "Swingman" <[email protected]> wrote:
>
> >"reaction wood"
>
> In pine though ? Unless you're pulling stock out of the firewood
> pile, most pines ought to be pretty straight. My money would still be
> on some moisture issue,
>
> I'm also puzzled by this heartwood/sapwood split - IMHE, pines don't
> have a strong distinction here and they don't go around splitting down
> it. This might be a diameter thing related to the drying. What
> species was it ?
On Fri, 3 Dec 2004 22:19:38 -0600, "Swingman" <[email protected]> wrote:
>"reaction wood"
In pine though ? Unless you're pulling stock out of the firewood
pile, most pines ought to be pretty straight. My money would still be
on some moisture issue,
I'm also puzzled by this heartwood/sapwood split - IMHE, pines don't
have a strong distinction here and they don't go around splitting down
it. This might be a diameter thing related to the drying. What
species was it ?
"Andy Dingley" wrote in message
> On Fri, 3 Dec 2004 22:19:38 -0600, "Swingman" wrote:
>
> >"reaction wood"
>
> In pine though ?
Absolutely ... compression wood is a type of reaction wood that is quite
common in pine. The symptoms of sawing or resawing compression wood are
identical to the experience the OP reported.
>My money would still be
>on some moisture issue,
Which may well be involved. Compression wood has a different specific
gravity and has a tendency to shrink more along lenght..
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