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3.5 in HDD platter hub
3.5 in HDD platter hub: Ø33 × 10 boss with a Ø8 shaft bore and M3 set-screw hole (Ø2.5), Ø25 × 1.27 spigot that takes the platter
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
| file | hub-platter-25-to-8 |
|---|---|
| disc | 3.5 in HDD platter |
| spigot | 25 |
| bore | 8 |
| outside | 33 |
| height | 12 |
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CD and HDD-platter flywheel hubs, Ø15 and Ø25 spigots: every size, notes, mating features and sources. How do I turn a CD or hard-drive platter into a flywheel?