Conical tapers include the category of standard machine tapers used throughout the tooling industry, classified as American Standard Self-Holding and Steep Taper series. See ASME B5.10. American Standard machine tapers are usually dimensioned by specifying the taper name and number. See Fig. 2-19, illustration (b). The diameter at the gage line and the length may also be specified. The taper in inches per foot and the diameter of the small end may be shown as reference. A conical taper may also be specified by one of the following methods:
(a) a basic taper and a basic diameter (see Fig. 2-21).
(b) a size tolerance combined with a profile of a surface tolerance applied to the taper (see para. 8.4.2).
(c) a toleranced diameter at both ends of a taper and a toleranced length. See Fig. 2-19, illustration (a).
NOTE: The method described in subpara. (c) is applicable for noncritical tapers, such as the transition between diameters of a shaft.
(d) a composite profile tolerance. Conical taper is the ratio of the difference in the diameters of two sections (perpendicular to the axis) of a cone to the distance between these sections.