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Alpha V-twin frame for two 10 mL syringes at 90°
What frame holds two syringes in a 90° V for an alpha Stirling engine? · Hardware · basis: Computed in the generator: crank throw 8, rod 60, 10 mL barrel 15.9 OD / 14.5 ID; checked over a full turn
Long Earth Society build part. The two-syringe alpha, complete. 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
- The one-piece frame of the two-syringe alpha: 140 × 52.45 × 128. A Ø24 boss holds the Ø5 crankshaft in two 625 bearings (Ø16 pockets at both ends, fit: press) with a Ø5.6 passage between.
- Two Ø15.9 barrel sockets (fit: socket) at ±45°, their axes meeting at the crank axis; the 90° between them is the alpha phase, with both con-rods on one crank pin.
- Socket inner faces at R45 from the crank axis: the piston skirt comes no closer than R43.4, so it never leaves the barrel. M3 pinch screws in Ø2.5 holes; foot with 2 × Ø5.5 at 50 mm for M5 into 2020.
Sizes
| parameter | value |
|---|---|
| outline | 140 × 52.45 × 128 |
| V angle | 90° |
| barrel sockets | 2 × Ø15.9 at ±45° |
| socket inner face | R45 |
| min skirt radius | 43.4 |
| bearing pockets | 2 × Ø16 (625) |
| foot | 2 × Ø5.5 at 50 |
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 |
|---|---|---|---|---|
| barrel sockets | Ø15.9 | 10 mL syringe barrel | socket | alpha-frame-* |
| bearing pockets | Ø16 | 625 bearing | press | alpha-frame-* |
| shaft passage between pockets | Ø5.6 | Ø5 shaft (no contact) | designed | alpha-frame-* |
| pinch-screw holes | Ø2.5 | M3 tap drill | designed | alpha-frame-* |
| foot holes | Ø5.5 | M5 clearance (ISO 273) | designed | alpha-frame-* |
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 |
| Wikipedia | Stirling engine (alpha configuration) | web | CC BY-SA 4.0 (text) |
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
| alpha-frame-10ml | alpha V-twin frame: Ø5 shaft in two 625s (pockets both ends of the Ø24 boss), two 10 mL barrel sockets at ±45° whose axes meet the crank axis, inner faces at R45, M3 pinch screws, foot with 2 × M5 at 50 mm for 2020 | STEP · STL |
Plain text: sheet.txt · JSON: /api/geometry?object=alpha-v-twin-syringe-frame
How it fits
Goes in or on
Plastic syringes 1–60 mL as pistons and cylinderstwo 10 mL barrels in the Ø15.9 sockets
Aluminium T-slot extrusion2 × M5 into 2020Connects to
Alpha V-twin crank disc Ø26, one pin, 16 mm strokeon the Ø5 shaft beside the bossAlternatives
Ross yoke alpha frame for two 10 mL syringesparallel-cylinder alphaAlso needed
Ball bearings, 683 to 6210 and flanged F6xx2 × 625
Transfer tee for 4 × 6 mm tubejoins the two syringe tipsIn these build lists
Alpha V-twin, two 10 mL syringesTwo 10 mL syringe barrels in a 90° V on one crank pin: the V is the 90° phase.You might also need
Questions
How do I get 90° phase on a two-syringe alpha Stirling?
Put the barrels in a 90° V with both con-rods on one crank pin; the V angle is the phase. This frame holds them at ±45°.
Why do the barrel sockets start 45 mm from the crank?
At bottom dead centre the piston skirt is 43.4 mm from the axis, so with the socket face at R45 the piston stays inside the barrel.