# Clamp-on water jacket for a 2 in tri-clamp tube, 20 mm, with hose spigots (optional)

> How do I water-cool a tri-clamp Stirling cooler without a jacketed spool?

- Category: Hardware › Stirling & thermoacoustic
- Kind: Hardware
- Basis: Design values: closed half-annular water chambers whose inner wall clamps on the Ø50.8 tube
- Page: https://xemstudio.com/objects/tri-clamp-clamp-on-water-jacket/ · JSON: https://xemstudio.com/api/geometry?object=tri-clamp-clamp-on-water-jacket · Plain text: https://xemstudio.com/objects/tri-clamp-clamp-on-water-jacket/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); linked files under their publishers' licenses
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

**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

- Two halves clamp onto the 3 in cooler spool above its hanger (2 × M4 × 12); each half is its own closed water chamber with a hose spigot in and out: run them in series. Heat to reject at the design point: about 53 W.
- Optional: without it, a wet cloth round the cooler spool or air alone will do for a short run at low charge; the engine's power falls as the cold end warms.

## 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 |
|---|---|---|---|---|
| bore | Ø50.8 | S3 tube OD | clamp | all |
| split | 1.0 total (0.5 per half) | the other half | clamp | all |
| hose spigots | Ø6 × 10, Ø4 bore | 6 mm ID hose | press | all |
| ear holes | Ø4.5 | M4 clearance (ISO 273 medium) | designed | all |

## Sizes

| feature | value |
|---|---|
| length | 20.0 |
| chamber | 5 deep, 1.5 walls |
| spigots | Ø6 × 10, Ø4 bore |

## Where the files are

- 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-clamp-on-water-jacket/index.json

- water-jacket-half-2in-20: [STEP](https://xemstudio.com/files/hardware/tri-clamp-clamp-on-water-jacket/water-jacket-half-2in-20.step) · [STL](https://xemstudio.com/files/hardware/tri-clamp-clamp-on-water-jacket/water-jacket-half-2in-20.stl) — water jacket half (optional): 20 long, inner wall on Ø50.8, closed 5 mm water chamber, hose spigots Ø6 × 10 (Ø4 bore), ears with one M4

## Questions

**Is it required?**

No: optional, like every heat exchanger on this engine.

## Fits with

- [Free-piston internal fin inserts: slotted heater and cooler sleeves for a 2 in tri-clamp bore (optional)](https://xemstudio.com/objects/fpse-fin-inserts/)
- [Tri-clamp spool (two ferrules on a tube), 1.5 and 2 inch](https://xemstudio.com/objects/tri-clamp-spool/)
- [Build list: Free-piston Stirling generator, 2 in tri-clamp (pressurised, linear alternator)](https://xemstudio.com/objects/list-fpse-generator-2in/)