Taper per Foot and Angle

Taper per foot and per inch, plus the included and per-side angles, from two diameters.

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Details, formula, and sources

Taper per foot, taper per inch, and the included and per-side angles of a taper from the large and small diameters and the length: TPF = 12 x (D - d) / L, angle/side = atan((D - d) / 2L) (first-principles trigonometry).

Taper per inch = (D - d) / L; taper per foot = TPI x 12; angle per side = atan((D - d) / (2L)); included angle = 2 x (angle per side).

Taper definitions and the taper-per-foot / angle relations - first-principles trigonometry as in Machinery's Handbook (Industrial Press), by name; public domain.

Pure trigonometry, public.

Estimate. AHJ and licensed professional govern.

Field names used by the API: large_dia_in, small_dia_in, length_in, tpf_in, tpi_in, angle_per_side_deg, included_angle_deg

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