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Ringbom displacer cap for an 8 mm rod, 2 in shell displacer
How do I fit a Ringbom rod to a tri-clamp displacer? · Hardware · basis: Shell spigot and flange as the displacer cap on this site (2 in shell Ø46 × 1 mm wall); Ø8 rod and M4 grub sizes are design values
Long Earth Society build part. The cap that turns my shell displacer into a Ringbom displacer. 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
- 1 in table
Notes
- Closes a 2 in shell displacer like the standard cap and holds an Ø8 rod instead of an Ø3 one. The rod is the Ringbom drive: its cross-section (50.3 mm²) times the gas pressure minus air pressure is the force that moves the free displacer.
- The rod's D-flat end goes in the Ø8 socket, 12 deep, and the M4 grub seats on the flat.
Sizes
| part | spigot_mm | flange_mm | boss_mm | socket_mm |
|---|---|---|---|---|
| ringbom-cap-2in-r8 | Ø44 × 3 | Ø46 × 1.5 | Ø16 × 14 | Ø8 × 12 |
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 |
|---|---|---|---|---|
| spigot | Ø44 × 3 | 2 in shell displacer bore | slide | all |
| rod socket | Ø8 × 12 | Ø8 rod D-flat end (M4 grub) | slide | all |
| grub hole | Ø3.3 | M4 tap drill | designed | all |
Where the files are
Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.
| Long Earth Society | Engine builds | 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
| ringbom-cap-2in-r8 | Ringbom displacer cap: Ø44 × 3 spigot into a 2 in shell displacer, Ø46 × 1.5 flange, Ø16 boss to 18.5 with an Ø8 socket 12 deep and an M4 grub (Ø3.3) | STEP · STL |
Plain text: sheet.txt · JSON: /api/geometry?object=tri-clamp-ringbom-displacer-cap
How it fits
In these build lists
Tri-clamp rolling-diaphragm Ringbom, 2 inThe simplest mechanism I could draw: one crank, one con-rod, and a free displace…You might also need
Questions
How strong is the Ringbom push?
50.3 mm² × the pressure difference: 0.5 N per 10 kPa, enough to lift about 51 g per 10 kPa.