Abstract: Helical shear blade cutter cooperable with a straight-edge bed plate for trimming fibers projecting from an article, including a shaft, and a blade in the form of a helical band wound edgewise on and about the shaft, the helical blade having a free edge forming a cutting edge from which a cutting face of the blade extends inwardly toward the shaft, the cutting face being formed with a serration to limit lateral yielding of the fibers as the fibers are being sheared by the cutting edge and the straight edge of the bed plate, the serration including saw-like teeth, respectively, having a short and a long flank, the long flank, in a condition wherein the shaft is disposed parallel to the straight-edge bed plate, forming a first angle with respect to the straight edge of the bed plate that is equal to the difference between a second angle formed by the cutting face of a blade without serrations formed therein and the straight edge of the bed plate and a third angle formed by the long flank and the cutting face of