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Split eccentric strap for Ø30 sheaves, 51 mm to the eye
What does an eccentric strap look like? · Hardware · basis: Ring Ø30 bore × Ø40 OD × 8 with a 1 mm split and a 40 × 10 arm ending in a Ø3 eye
Long Earth Society build part. Quiet displacer and pump drive used on the LES rigs. 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
- 7 in table
Notes
- A ring Ø30 bore × Ø40 OD × 8 with a 1 mm split through the side opposite the arm, so it goes over the sheave without taking the shaft apart.
- A 40 × 10 arm ends in a Ø3 eye 51 mm from the ring's centre. Overall 75 × 40 × 8.
- The Ø30 bore turns on the sheave and a Ø3 pin in the eye drives the next link; fits are under Mating features.
Sizes
| feature | value_mm |
|---|---|
| bore | Ø30 |
| ring OD | Ø40 |
| thickness | 8 |
| split | 1.0 |
| arm | 40 × 10 |
| eye | Ø3 at 51 |
| overall | 75 × 40 × 8 |
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 |
|---|---|---|---|---|
| strap bore | Ø30 | Ø30 eccentric (turns in it) | run | eccentric-strap-* |
| strap split | 1.0 | closes on the eccentric | clamp | eccentric-strap-* |
| strap eye | Ø3 | Ø3 pin (turns in it) | run | eccentric-strap-* |
Where the files are
Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.
| Wikipedia | Eccentric (mechanism) | web | CC BY-SA 4.0 (text) |
| Long Earth Society | Engine and rig builds on extrusion frames | 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=eccentric-strap
How it fits
Goes in or on
Eccentric sheaves Ø30 at 3, 5 and 8 mm offsetØ30 bore on the sheaveConnects to
Four-bar linksØ3 eye to the linkAlso needed
Crank and wrist pins Ø3 × 12, 16, 19, 20 and 23Ø3 pin in the eyeYou might also need
Questions
How does the strap go on?
Through the 1 mm split, over the Ø30 sheave.
Where is the strap eye?
Ø3, 51 mm from the strap centre.