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ISO 4156 30° flat-root external spline shaft section, module 1, 20 teeth

ISO 4156 30° flat-root external spline shaft section, module 1, 20 teeth: pitch Ø20 mm, major Ø21 mm, minor (root) Ø18.5 mm; basic tooth (thickness half the circular pitch, no tolerance, effective-variation shift esv = 0), true involute flank carried down to the root circle (root fillet not modelled); the 25 mm length is an example, no chamfer, no bore

Exact dimensions. True size, no tolerance added. Threads are plain cylinders at the major diameter.

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From the full sheet

Involute splines ISO 4156 (metric module, 30° side fit): pitch, major and minor diameter by module and tooth count + example shaft STEP/STL: every size, notes, mating features and sources. What are the pitch, major and minor diameters of an ISO 4156 involute spline for module 2 and 24 teeth?

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