Polynomial degree in direction of the tooth depth (right flank)

The parameters of the Bezier surface for the left and right sides of the pinion and gear can be specified individually for the flank and root. When specifying the polynomial degree, a distinction is made in the width and profile direction according to the coordinates R and θ for the flank and R and u in the root. This allows specific modeling of the surfaces.

The polynomial degrees of the effective flank and root Bezier surfaces are preset to 5 by default. This is always sufficient for the wheel gear. For very twisted pinion flanks with a small number of teeth and a large helix angle, it may be necessary to increase the polynomial degree of the effective flank fitting surface (recommendation: polynomial degree = 9 for flank and tooth root). This also applies to tooth flanks with a very small spherical protuberance radius.

Different polynomial degrees in the face width and tooth depth directions are not necessary in most cases and should be avoided.

Source: BECAL user manual and program documentation (in German).