Method for grading a wood sample based on pith direction and/or pith location

1. A method for grading a wood sample comprising the steps of:

examining visual characteristics of the wood sample using visual scanning equipment;

determining pith direction from the visual characteristics;

determining pith location by:

selecting two areas of the wood sample at which two or more chords of a ring can be defined;

bisecting the chords to define a line perpendicular to the chords;

locating at least one intersection point P for two or more of the bisecting perpendicular lines;

wherein P is the pith location; and

grading the wood sample based on the pith location.

2. The method of claim 1 wherein the step of determining pith direction comprises the steps of:

finding two or more pith vectors on two or more surfaces on the wood sample; and

determining a direction for each of the two or more pith vectors

wherein the direction is determined based on a latewood to earlywood boundary.

3. The method of claim 1 wherein the step of determining pith direction is determined is performed by examining faces of the wood sample.

4. The method of claim 1 wherein the step of determining pith direction is determined based on at least one ratio of ring spacing on opposite or adjacent faces of the wood sample.

5. A method for grading a wood sample comprising the steps of:

examining visual characteristics of the wood sample using visual scanning equipment;

using visual scanning equipment to find two or more pith vectors from the two or more surfaces on the wood sample;

determining a direction for each of the pith vectors wherein the direction is determined based on a latewood to earlywood boundary;

determining pith direction based on whether the two or more pith vectors are oriented towards or away from one another; and

grading the wood sample based on the pith direction.

6. The method of claim 5 wherein the step of determining pith direction based on whether the two or more pith vectors are oriented towards or away from one another comprises:

identifying a ring intersecting adjacent faces of the wood sample where the pith vectors are directed toward each other.

7. The method of claim 5 wherein the step of determining pith direction based on whether the two or more pith vectors are oriented towards or away from one another comprises:

identifying a ring intersecting adjacent faces of the wood sample where the pith vectors are directed away from each other.

8. A method for grading a wood sample comprising the steps of:

examining visual characteristics of the wood sample using visual scanning equipment;

determining at least two pith vectors using the visual scanning equipment on adjacent faces of the wood sample;

selecting a corner common to the adjacent faces of the wood sample based on whether the at least two pith vectors are oriented towards or away from one another;

selecting end points of a ring that intersects the adjacent faces in the corner;

defining one or more chords between the end points;

bisecting the one or more chords to define a line perpendicular to the one or more chords;

locating at least one intersection point P for two or more of the bisecting perpendicular lines, wherein P indicates the pith location; and

grading the wood sample based on the pith location.

9. The method of claim 1 wherein the step of examining visual characteristics of the wood sample using visual scanning equipment is performed by a scanning electron microscope.

10. The method of claim 5 wherein the step of examining visual characteristics of the wood sample using visual scanning equipment is performed by a scanning electron microscope.

11. The method of claim 8 wherein the step of examining visual characteristics of the wood sample using visual scanning equipment is performed by a scanning electron microscope.