Xem Studiomeasured geometryLibrary › Hardware › Roller chain sprockets: #25 (6.35 mm) and #35 (9.525 mm), 10–40 T
sprocket-25-20t-b8
#25 chain (6.35 mm pitch), 20 T, PD 40.59, tip Ø39.27, roller seat Ø3.393, Ø17.6 × 8 hub, Ø8 bore, M3 set screw (Ø2.5 tap drill)
Exact dimensions. True size, no printing tolerance added. Threads are plain cylinders at the major diameter.
STEP STL free, CC BY 4.0 (credit "Xem Studio")
Dimensions
| chain | #25 |
|---|---|
| teeth | 20 |
| pitch_dia_mm | 40.59 |
| od_mm | 39.27 |
| pitch_mm | 6.35 |
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Roller chain sprockets: #25 (6.35 mm) and #35 (9.525 mm), 10–40 T: every size, notes, mating features and sources. What is the pitch diameter of a 20 tooth #25 sprocket?