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Pawl 24 mm with a Ø3 pivot for the Ø40 ratchet wheels
How is a pawl for a ratchet wheel shaped? · Hardware · basis: Pawl 24 mm from pivot to tip, 8 wide, 6 thick, Ø10 boss with a Ø3 pivot hole
Long Earth Society build part. Anti-reverse for the LES flywheel generators; same mechanism as a reel's clicker. The engines
Exact dimensions. Every file is drawn at true size with no printing tolerance. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your printer's or process's clearance before making the part. Mating features
- sizes
- 6 in table
Notes
- A flat pawl 6 thick: a Ø10 boss with a Ø3 pivot hole, an 8 mm wide arm and a pointed tip 24 mm from the pivot. Overall 29 × 10 × 6.
- It turns on a Ø3 pin; the tip locks against a tooth face and the sloped tooth backs lift it on the free stroke.
- Its contact point trails the pivot in the locking direction so load drives it into the tooth; a spring holds it down (not drawn).
Sizes
| feature | value_mm |
|---|---|
| pivot to tip | 24 |
| arm width | 8 |
| thickness | 6 |
| pivot boss | Ø10 |
| pivot hole | Ø3 |
| overall | 29 × 10 × 6 |
Mating features
Drawn at the exact size. Open press, slide, run and socket features by your process's clearance; leave designed gaps and clamp fits as drawn.
| feature | exact | mates with | fit | files |
|---|---|---|---|---|
| pawl pivot hole | Ø3 | Ø3 pin (pawl turns on it) | run | pawl-* |
Where the files are
Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.
| Wikipedia | Ratchet (device) | web | CC BY-SA 4.0 (text) |
| Wikipedia | Pawl | web | CC BY-SA 4.0 (text) |
| Long Earth Society | Engine builds that use these parts (videos and write-ups) | web, video | LES site |
Free files
★ Free files 1 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json
Plain text: sheet.txt · JSON: /api/geometry?object=ratchet-pawl
How it fits
Connects to
Ratchet wheels Ø40 with 12, 24 and 36 teethtip on the Ø40 wheel's teethAlso needed
Crank and wrist pins Ø3 × 12, 16, 19, 20 and 23Ø3 pivot pin
Torsion spring wire Ø0.8, OD 8, 6 coilspawl returnYou might also need
Questions
Which way does the pawl point?
Its contact point trails the pivot in the locking direction, so load drives it into the tooth.
What does the pawl pivot on?
A Ø3 pin through its Ø3 hole.