Prometheus wrote:
On 20 May 2005 13:56:48 -0700, "SonomaProducts.com"

wrote:

I've always wondered if the figuring can be attributed to any
specifc
condition of the tree. I always though maybe some burl like growth
might signal quilting or a very wind blown/bent tree might have some
tigerring. Let us know if you "figure" anything out.

I was roughing out a birch blank on the lathe tonight after work, and
noted that there was a pretty good tiger figure beneith the crotch
where a good sided branch had been. It appeared to me like the
weight
of the branch had somehow compressed the grain underneith, and caused
the pattern by buckling the fibers slightly. I don't know if that
was
the case, but it was something to wonder about anyhow!

Indeed it looks like that and there is ample folklore to that effect.
However if you find a long section of trunk that is curly it will
be curly all around, not just on one side, for the reasons explained
below.


One nice aspect about Maple is that the figure tends to be deep
within
each board so you should be able to find it pretty easily. I know
with
QS White Oak you can plane a 1/4" off and lose all the figure. I've
resawn nice looking boards only to find no figure in the middle.

If you lost the ray flecks you most have sawn off the grain that was
perpendicular to the face of the board. Keep in mind that ray flecks
and curl are entirely different figure.


The only one that doesn't seem to go all that deep in maple is bird's
eye. I found that out the hard way when I made a lamp out of some,
and ended up with regular old maple where a lot of excellent figure
used to be. Curly figure usually seems to go all the way through.

I wonder if it matters the direction of the cut through the log.
Maybe
you take a slice first and try splitting it in different directions
looking for a figure pattern. Sorta cut it like a pizza.

Casual observation indicates that bird's eye shows up best on a flat-
sawn face. Quarter sawn bird's eye looks like curl, though true
curly wood is curly no matter how you slice it.


I imagine it would- look at the difference between flat-sawn and
quarter-sawn. I don't believe I've ever seen flecks in flat-sawn
oak.

Curly figure in maple is not related to flecks. You can see flecks
in flat sawn oak, they are very very thin dark streaks in between the
grain boundaries. In Oak and beech flecks are also prominent in
the end-grain. You can also see flecks in maple and cherry, but
only if it is very precisely quarter sawn, that is with the grain
very close to perpendicular to the wood surface. The flecks in
maple and cherry look rather like fish scales. They are very
small and numerous.

All wood has ray flecks, they are cellular structures that grow
perpendicular to the growth rings and knit the layers of wood
together. In most woods they are very small and so hard to see.
In oak, beech, sycamore, lacewood (Australian silky oak) they
stand out in quarter sawn wood, most of all in oak.

Curly figure in wood is caused by irritation of the cambrium
by a fungus resulting in an abnormal growth pattern. It is
most common in and near stumps and crotches, places where
moisture accumulates and encourages the fungal growth.

Where curly figure occurs in a trunk the grain does not
run vertically up and down the trunk as in normal growth
for most trees, but spirals around the trunk. For that
reason, any curly maple boards you see that were cut
symetrically with respect to the centerline of the trunk
will have approximately equally curly left and right margins
and the outermost margins will have a 'curlier' figure than
the heartwood. That is not a quartersawn vs.flatsaw effect
as can eb demonstrated by observing that edge (arris) of a
quartersawn curly board (which is a flatsawn face) is as
culry as the quartersawn face.

Because curly wood grows in a spiral around the trunk all
boards cut parallel to the axis of the tree, whether flat,
rift, or sawn will be short grained. This makes curly wood
unsuitable for things like drumsticks, hammer handles and
the uprights on frame saws. Curly boards easily break when
laoded in bending. It is commonly said that the curls run
perpendicular to the grain. This is not true. The curls
run perpendicular to the apparent grain direction, but the
apparent grain is skewed with respect to the true grain.
If you bend a piece of curly wood until it breaks and
observe how it breaks you will see that the grain runs
at about a thirty degree angle with respect to the
apparent grain direction.

The same fungus is supposed to be responsible for curl, quilting,
and bird's eye. I _think_ that bird's eyes form where tiny
leaves grow out directly from the trunk and are analogous
to needle scars in softwoods.

--

FF