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Displacer rods Ø2 × 60, 78, 100 and 180, Ø3 × 100, 150 and 200
What size rod connects a Stirling displacer to its crank? · Hardware · basis: Solid rods at the bore Ø of the parts they pass through: Ø3 for the tri-clamp heads, Ø2 for the can-engine cap and LTD top plate
Long Earth Society build part. The shafts, rods and pins every engine here turns on. 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
- Solid rods with 0.3 chamfers at both ends, plain round, no flat: Ø3 × 100, 150 and 200, and Ø2 × 60, 78, 100 and 180.
- On the tri-clamp engines the rod runs from the displacer cap's socket (M3 grub) up through the head's Ø3 bore, which is its guide and seal, to the rod clevis.
- Rod length = displacer cap to clevis plus the stroke.
- On the can engine and the LTD engines the Ø2 rod runs through the Ø2 bore in the can cap or the LTD top plate, from the displacer (flush with its underside) to the rod-clevis-2mm: 180 on the can engine, 76 on the Ø100 LTD.
- On the rhombic and free-piston engines the same Ø3 rod runs up the inside of the Ø5 tube piston rod (Ø3.4 bore).
Sizes
| file | Ø | length |
|---|---|---|
| rod-2x60 | 2 | 60 |
| rod-2x76 | 2 | 78 |
| rod-2x100 | 2 | 100 |
| rod-2x180 | 2 | 180 |
| rod-3x100 | 3 | 100 |
| rod-3x150 | 3 | 150 |
| rod-3x200 | 3 | 200 |
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 |
|---|---|---|---|---|
| shafts, rods, pins | Ø3 / Ø5 / Ø8 | the bores listed on each mating object | slide | 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 7 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json
| rod-3x100 | Ø3 × 100 solid rod: displacer rod (into the displacer cap's grub, through the head's Ø3 bore and the piston crown, into the rod clevis) | STEP · STL |
| rod-3x150 | Ø3 × 150 solid rod: displacer rod (into the displacer cap's grub, through the head's Ø3 bore and the piston crown, into the rod clevis) | STEP · STL |
| rod-3x200 | Ø3 × 200 solid rod: displacer rod (into the displacer cap's grub, through the head's Ø3 bore and the piston crown, into the rod clevis) | STEP · STL |
| rod-2x60 | Ø2 × 60 solid rod: displacer rod for the can and LTD engines (through the Ø2 bore in the can cap or LTD top plate; 76 is the LTD's, 180 the can engine's, displacer to rod clevis) | STEP · STL |
| rod-2x76 | Ø2 × 76 solid rod: displacer rod for the can and LTD engines (through the Ø2 bore in the can cap or LTD top plate; 76 is the LTD's, 180 the can engine's, displacer to rod clevis) | STEP · STL |
| rod-2x100 | Ø2 × 100 solid rod: displacer rod for the can and LTD engines (through the Ø2 bore in the can cap or LTD top plate; 76 is the LTD's, 180 the can engine's, displacer to rod clevis) | STEP · STL |
| rod-2x180 | Ø2 × 180 solid rod: displacer rod for the can and LTD engines (through the Ø2 bore in the can cap or LTD top plate; 76 is the LTD's, 180 the can engine's, displacer to rod clevis) | STEP · STL |
Plain text: sheet.txt · JSON: /api/geometry?object=displacer-rods
How it fits
Goes in or on
Tri-clamp displacerØ3 rod in the displacer cap socket and the head's Ø3 bore
Tube piston rods Ø5 × Ø3.4runs inside the Ø3.4 bore
Can-engine cap for 53.3, 58, 66 and 76.2 mm cansØ2 rod in the cap's Ø2 bore
LTD Stirling top plate with syringe socket, Ø120…Ø2 rod in the top plate's Ø2 boreConnects to
Rod clevises for a Ø2 or Ø3 rod or a Ø5 tube, 5…Ø3 socket with M3 grubIn these build lists
Gamma Stirling, 2 in tri-clampHot spool with a shell displacer, a crank head that carries the crankshaft, the …Soda-can gammaA 12 oz can as the displacer cylinder over a tea light, a 10 mL syringe barrel a…Beta Stirling, rhombic drive, 2 in tri-clampDisplacer and piston in one bore, driven by two counter-rotating gears on a rhom…LTD coffee-cup engineRuns on a cup of coffee: wide thin displacer, small piston.Free-piston Stirling, 2 in tri-clampNo crank: piston and displacer each hang on a stack of spiral flexures, with a t…Tri-clamp tee diaphragm gamma, 2 inA tea-light gamma in 2 in tri-clamp: displacer in a 3 in spool, a short-outlet t…Tri-clamp elbow diaphragm alpha, 2 inA torch-heated alpha in 2 in tri-clamp: a square of fittings with a diaphragm he…Mug LTD (sits on a coffee mug)You might also need
Questions
What diameter is the displacer rod?
Ø3 on the tri-clamp engines, where it slides in the head's Ø3 bore and seats in the displacer cap and rod clevis sockets. Ø2 on the can engine and LTD engines, through the Ø2 bore in the cap or top plate.
How long should the displacer rod be?
Displacer cap to rod clevis plus the stroke; the files are 100, 150 and 200 long.