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20 DP spur gear, 28 teeth, 20° pressure angle

20 DP spur gear, 28 teeth, 20° pressure angle: pitch Ø35.560 mm (1.4 in), outside Ø38.100 mm (1.5 in), root Ø32.410 mm; face 9.52 mm (3/8 in) and bore Ø9.525 mm (3/8 in) are examples, the tooth form is the standard's; true involute flanks, no hub, keyway, chamfer or root fillet

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

STEP STL free, CC BY 4.0 (credit "Xem Studio")

Dimensions

teeth N28
pitch Ø = N / DP, in (mm)1.4 (35.56)
outside Ø = (N + 2) / DP, in (mm)1.5 (38.10)
root Ø 14.5°, in (mm)1.276 (32.41)
root Ø 20°, in (mm)1.276 (32.41)
base Ø 14.5°, in (mm)1.3554 (34.43)
base Ø 20°, in (mm)1.3156 (33.42)
example face, in3/8
example bore, in3/8
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From the full sheet

Spur gears, 20 diametral pitch (DP): 12 to 60 teeth, 14.5° and 20° involute, pitch / outside / root diameter and STEP/STL: every size, notes, mating features and sources. What is the pitch diameter, outside diameter and root diameter of a 20 DP spur gear, and how many teeth does it have?

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