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12 DP spur gear, 12 teeth, 20° pressure angle

12 DP spur gear, 12 teeth, 20° pressure angle: pitch Ø25.400 mm (1 in), outside Ø29.633 mm (1.1667 in), root Ø20.108 mm; face 17.46 mm (11/16 in) and bore Ø6.350 mm (1/4 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 N12
pitch Ø = N / DP, in (mm)1 (25.40)
outside Ø = (N + 2) / DP, in (mm)1.1667 (29.63)
root Ø 14.5°, in (mm)0.8072 (20.50)
root Ø 20°, in (mm)0.7917 (20.11)
base Ø 14.5°, in (mm)0.9681 (24.59)
base Ø 20°, in (mm)0.9397 (23.87)
example face, in11/16
example bore, in1/4
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From the full sheet

Spur gears, 12 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 12 DP spur gear, and how many teeth does it have?

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