# Frame for the 2 in tri-clamp elbow diaphragm alpha

> What holds the tri-clamp elbow diaphragm alpha together?

- Category: Hardware › Stirling & thermoacoustic
- Kind: Hardware
- Basis: Positions from the engine layout (tools/gen_diaphragm.py alpha_layout); the feet seats are cut by the fittings' own outer surfaces
- Page: https://xemstudio.com/objects/tri-clamp-diaphragm-alpha-frame/ · JSON: https://xemstudio.com/api/geometry?object=tri-clamp-diaphragm-alpha-frame · Plain text: https://xemstudio.com/objects/tri-clamp-diaphragm-alpha-frame/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); linked files under their publishers' licenses

**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.

## Notes

- One piece: a base plate, a foot under the elbow (its seat is the elbow's outer surface) that carries the cold leg, a foot under the capped run of the hot tee, and a diagonal strut from the base up to a bearing block with two 625 pockets at the crank.
- The strut runs 40–56 mm behind the plane of the legs, clear of every clamp and of the flywheel.

## Mating features (exact size; open press / slide / run / socket by your process clearance, leave designed and clamp as drawn)

| feature | exact | mates with | fit | files |
|---|---|---|---|---|
| bearing pockets | Ø16 × 5 | 625 bearing | press | alpha-frame-* |
| shaft passage | Ø11.2 | Ø5 crankshaft (no contact) | designed | alpha-frame-* |
| foot seats | Ø50.8 (tube OD), elbow outer surface | 2 in elbow and tee | designed | alpha-frame-* |
| torch-stand holes | Ø4.5 | M4 clearance (ISO 273 medium) | designed | alpha-frame-* |

## Sizes

| feature | value |
|---|---|
| base | 430 × 130 × 8 |
| crank above elbow centre | 257.4, 257.4 |
| bearings | 2 × 625 |

## Where the files are

- ISO: [ISO 273 clearance holes for bolts and screws (fine / medium / coarse)](https://www.iso.org/standard/4196.html) — standard — dimensions are facts (verify at link)
- Long Earth Society: [Engine builds](https://longearthsociety.com/engineering/) — web, video — LES site

## Free STEP/STL (1 parts, CC BY 4.0, Xem Studio)

Index: https://xemstudio.com/files/hardware/tri-clamp-diaphragm-alpha-frame/index.json

- alpha-frame-2in: [STEP](https://xemstudio.com/files/hardware/tri-clamp-diaphragm-alpha-frame/alpha-frame-2in.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-diaphragm-alpha-frame/alpha-frame-2in.stl) — frame for the 2 in elbow diaphragm alpha: base 430 × 130 × 8, feet under the elbow and the hot tee, diagonal strut to a bearing block with two 625 pockets at the crank (257.4, 257.4) from the elbow centre

## Questions

**What does the frame carry?**

Both legs (two feet), the crankshaft bearings (strut block) and the torch stand (two M4 holes).

## Fits with

- [Build list: Tri-clamp elbow diaphragm alpha, 2 in](https://xemstudio.com/objects/list-tri-clamp-elbow-diaphragm-alpha/)