Colorimetric Analysis in Grading Black Walnut Veneer

Abstract

Colorimetry techniques and automated data collection instrumentation were used to evaluate grade of black walnut veneer on the basis of sheet color and to identify and classify defects by size.Although color measurement readily quantifies veneer color, relatively large differences in color within sheets and between sheets within a veneer grade make the usefulness of overall color values in grading black walnut veneer doubtful under current grading practices.Differentiation between sapwood and heartwood is easily determined and may have commercial application in veneer clipping operations.Colorimetry techniques can detect defects with reasonable consistency, but accurate size classification needs more study.